Version 7 INSPEC / Search:cPbL Aug 12 2000: The following is done in N steps, using an "add-on search" (just as written, below), since the command length is limited in folio. (paste as one paste). Find SUBJECT MESOSPHERE LIGHTNING or SUBJECT SPRITE LIGHTNING OR SUBJECT STRATOSPHERE LIGHTNING OR SUBJECT "UPWARD ELECTRICAL DISCHARGE" LIGHTNING or title clear air lightning or title cloud space lightning or cloud ionosphere lightning or subject thunderstorm stratosphere luminous or a sentman, d.d. or s sprite spectra band or SUBJECT HIGH ALTITUDE DISCHARGE RADAR ECHOES or SUBJECT GAMMA RAY ATMOSPHERIC INTENSE FLASHES or SUBJECT BLUE IMAGERY SPRITES or SUBJECT HIGH SPEED VIDEO SPRITE DEVELOPMENT or SUBJECT FRACTAL SPRITES Result: 213 citations Other notes - Axiom finds SUBJECT cloud-to-space OR subject cloud-to-ionosphere, but folio Inspec doesn't. - Search for /sub 2/ --> $_2$ to find subscripts that need TeX-ifying. Note: "Conference proceedings" still needs to be programmed into the Perl script. --------------------------------------------------------------------------- The following references are missing from INSPEC: --------------------------------------------------------------------------- @ARTICLE{Vaughan89, author={Vaughan, O. H., Jr. and Vonnegut, B.}, title={Recent observations of lightning discharges from the top of a thundercloud into the clear air above}, journal={Geophysical Research Letters}, volume={94}, number={}, year={1989}, month={}, pages={13179} } ---------------------------------------------------------------------------- The following are from the large search, described at the top of this document -------------------------------------------------------------------------- /usr/tmp/citation.tmp.27694 @ARTICLE{StanleyMar00, author={Stanley, M. and Brook, M. and Krehbiel, P. and Cummer, S.A.}, title={ Detection of daytime sprites via a unique sprite ELF signature }, journal={Geophysical Research Letters}, volume={27}, number={6}, year={2000}, month={Mar}, pages={871-4}, abstract={ On August 14, 1998, three separate daytime sprite events were detected via a unique extremely low frequency (ELF) sprite signature. The onset of the sprite ELF signatures was delayed by 11.0-13.2 ms from positive cloud-to-ground strokes which had attained exceptionally large charge moment (charge times height) changes of 3900-6100 C.km. It is shown that a charge moment change of 6100 C.km may have been sufficient for conventional breakdown at approximately=54 km altitude, assuming an experimentally measured ion conductivity profile of Holzworth et al. (1985). The daytime sprites themselves contained unusually large charge moment changes of approximately=2890 C.km, approximately=1200 C.km, and approximately=910 C.km }, keywords={ ionospheric electromagnetic wave propagation ionospheric techniques lightning radiowave propagation daytime sprite detection sprite ELF signature AD 1998 08 14 positive cloud-to-ground strokes ion conductivity profile charge moment changes 54 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HardmanFeb00, author={Hardman, S.F. and Dowden, R.L. and Brundell, J.B. and Bahr, J.L. and Kawasaki, Z. and Rodger, C.J.}, title={ Sprite observations in the Northern Territory of Australia }, journal={J. Geophys. Res. (USA), Journal of Geophysical Research}, volume={105}, number={D4}, year={2000}, month={Feb}, pages={4689-97}, abstract={ Sprites, a form of brief luminous discharge in the upper atmosphere above a thunderstorm, were observed and imaged on two video cameras in Australia's Northern Territory. These were the first such ground-based observations made outside the United States. Sprite discharges typically took place between the altitudes of 50 km and 80 km and spanned an average width of 44 km. Many of the sprite events were of long duration, with an average of 145 ms. These spatial and temporal features were similar to those observed from the ground and the air in the United States. During the longer events, some luminous discharge elements were observed to decay as other new elements formed. As the new elements were often laterally displaced from the old, the sprites sometimes appeared to dance across the sky. This phenomenon has been observed in Colorado and named "dancing sprites". The lateral progression of sprite elements observed in the Northern Territory was overwhelmingly in one direction and covered distances of up to 90 km }, keywords={ airglow atmospheric radiation lightning mesosphere thunderstorms mesosphere middle atmosphere sprite lightning optical emission Northern Territory Australia luminous discharge thunderstorm ground-based observations duration dancing sprite lateral progression 50 to 90 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{AllenFeb00, author={Allen, D. and Pickering, K. and Stenchikov, G. and Thompson, A. and Kondo, Y.}, title={ A three-dimensional total odd nitrogen (NO/sub y/) simulation during SONEX using a stretched-grid chemical transport model }, journal={Journal of Geophysical Research}, volume={105}, number={D3}, year={2000}, month={Feb}, pages={3851-76}, abstract={ The relative importance of various odd nitrogen (NO/sub y/) sources including lightning, aircraft, and surface emissions on upper tropospheric total odd nitrogen is illustrated as a first application of the three-dimensional Stretched-Grid University of Maryland/Goddard Chemical-Transport Model (SG-GCTM). The SG-GCTM has been developed to look at the effect of localized sources and/or small-scale mixing processes on the large-scale or global chemical balance. For this simulation the stretched grid was chosen so that its maximum resolution is located over eastern North America and the North Atlantic; a region that includes most of the Subsonic Assessment (SASS) Ozone and Nitrogen Oxide Experiment (SONEX) flight paths. The SONEX period (October-November 1997) is simulated by driving the SG-GCTM with assimilated data from the Goddard Earth Observing System-Stratospheric Tracers of Atmospheric Transport Data Assimilation System (GEOS-STRAT DAS). A new algorithm is used to estimate the lightning flash rates needed to calculate NO/sub y/ emission by lightning. This algorithm parameterizes the flash rate in terms of upper tropospheric convective mass flux. Model-calculated upper tropospheric NO/sub y/ and NO/sub y/ measurements from the NASA DC-8 aircraft are compared. Spatial variations in NO/sub y/ were well captured especially with the stretched-grid run; however, model-calculated peaks due to "stratospheric" NO/sub y/ are occasionally too large. The lightning algorithm reproduces the temporally and spatially averaged total flash rate accurately; however, the use of emissions from observed lightning flashes significantly improves the simulation on a few days, especially November 3, 1997, showing that significant uncertainty remains in parameterizing lightning in chemistry and transport models }, keywords={ air pollution atmospheric composition atmospheric movements nitrogen compounds troposphere atmosphere stratosphere troposphere air pollution chemical composition aircraft emission three-dimensional model NO/sub y/ model simulation AD 1997 SONEX stretched-grid chemical transport model numerical model lightning surface emission North Atlantic North America algorithm transport model NO$_2$ NO/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MeijerFeb00, author={Meijer, E.W. and van Velthoven, P.F.J. and Thompson, A.M. and Pfister, L. and Schlager, H. and Schulte, P. and Kelder, H.}, title={ Model calculations of the impact of NO/sub x/ from air traffic, lightning, and surface emissions, compared with measurements }, journal={Journal of Geophysical Research}, volume={105}, number={D3}, year={2000}, month={Feb}, pages={3833-50}, abstract={ The impact of NO/sub x/ from aircraft emissions, lightning, and surface contributions on atmospheric nitrogen oxides and ozone in the North Atlantic flight corridor has been investigated with the three-dimensional global chemistry transport model TM3 by partitioning the nitrogen oxides and ozone according to source category. The results have been compared with Pollution from Aircraft Emissions in the North Atlantic flight corridor (POLINAT 2) and Subsonic Assessment Ozone and Nitrogen Oxide Experiment (SONEX) airborne measurements in the North Atlantic flight corridor in 1997. Various cases have been investigated: measurements during a stagnant anticyclone and an almost cutoff low, both with expected high aircraft contributions, a southward bound flight with an expected strong flight corridor gradient and lightning contributions in the south, and a transatlantic flight with expected boundary layer pollution near the U.S. coast. The agreement between modeled results and measurements is reasonably good for NO and ozone. Also, the calculated impact of the three defined sources was consistent with the estimated exposure of the sampled air to these sources, obtained by specialized back trajectory modeled products. Model calculations indicate that aircraft contributes 55% to the mean NO/sub x/ concentration and 10% to the O/sub 3/ concentration in the North Atlantic flight corridor in October 1997, whereas lightning and surface emissions add 15% and 25% to the NO/sub x/ concentration and 20% and 30% to the O/sub 3/ concentration }, keywords={ air pollution atmospheric composition atmospheric movements stratosphere troposphere atmosphere stratosphere troposphere chemical composition air pollution model calculation NO/sub x/ air traffic lightning surface emission aircraft North Atlantic flight corridor three-dimensional model global chemistry transport model TM3 stagnant anticyclone cutoff low AD 1997 mesoscale meteorology NO }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HannanFeb00, author={Hannan, J.R. and Fuelberg, H.E. and Thompson, A.M. and Bieberbach, G., Jr. and Knabb, R.D. and Kondo, Y. and Anderson, B.E. and Browell, E.V. and Gregory, G.L. and Sachse, G.W. and Singh, H.B.}, title={ Atmospheric chemical transport based on high-resolution model-derived winds: a case study }, journal={Journal of Geophysical Research}, volume={105}, number={D3}, year={2000}, month={Feb}, pages={3807-20}, abstract={ Flight 10 of NASA's Subsonic Assessment (SASS) Ozone and Nitrogen Oxide Experiment (SONEX) extended southwest of Lajes, Azores. A variety of chemical signatures was encountered. These signatures are examined in detail, relating them to meteorological data from a high-resolution numerical model having a horizontal grid spacing of 30 and 90 km with 26 vertical levels. The meteorological output at hourly intervals is used to create backward trajectories from the locations of the chemical signatures. Four major categories of chemical signatures are discussed: stratospheric, lightning, continental pollution, and a mixed chemical layer. The strong stratospheric signal is encountered just south of the Azores in a region of depressed tropopause height. Three chemical signatures at different altitudes in the upper troposphere are attributed to lightning. Backward trajectories from these signatures extend to locations of cloud-to-ground lightning. Specifically, results show that the trajectories pass over regions of lightning 1-2 days earlier over the eastern Gulf of Mexico and off the southeast coast of the United States. The lowest leg of the flight exhibits a chemical signature consistent with continental pollution. Trajectories from this signature are found to pass over the highly populated Northeast Corridor of the United States. Surface-based pollution apparently is lofted to the altitudes of the trajectories by convective clouds along the East Coast that did not contain lightning. Finally, a mixed layer is described. Its chemical signature is intermediate to those of lightning and continental pollution. Backward trajectories from this layer pass between the trajectories of the lightning and pollution signatures }, keywords={ air pollution atmospheric composition atmospheric movements troposphere wind North Atlantic marine atmosphere troposphere stratosphere air pollution circulation trajectory chemical composition chemical transport high-resolution model wind dispersion SASS SONEX Lajes AD 1997 Azores backward trajectories lightning mixed chemical layer continental pollution United States Northeast Corridor }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{JekerFeb00, author={Jeker, D.P. and Pfister, L. and Thompson, A.M. and Brunner, D. and Boccippio, D.J. and Pickering, K.E. and Wernli, H. and Kondo, Y. and Staehelin, J.}, title={ Measurements of nitrogen oxides at the tropopause: attribution to convection and correlation with lightning }, journal={Journal of Geophysical Research}, volume={105}, number={D3}, year={2000}, month={Feb}, pages={3679-700}, abstract={ NO/sub x/ (NO and NO$_2$) and ozone were measured on 98 flights during August to November 1997 in the framework of the projects Pollution From Aircraft Emissions in the North Atlantic Flight Corridor (POLINAT 2) and Subsonic Assessment Ozone and Nitrogen Oxide Experiment (SONEX). The fully automated measurement system Nitrogen Oxides and Ozone Along Air Routes (NOXAR) was permanently installed aboard an in-service Swissair B-747 airliner operating in the North Atlantic Flight Corridor. Below the tropopause, predominantly over the U.S. east coast, the patchy occurrence of NO/sub x/ enhancements up to 3000 parts per trillion by volume (pptv) was observed frequently and led to a lognormal probability density function of NO/sub x/. These plumes extend over several hundred kilometers. In three case studies the origin of such plumes was investigated using back trajectories, satellite infrared images, and lightning observations from the U.S. National Lightning Detection Network (NLDN) and the Optical Transient Detector (OTD) satellite instrument. In the case of frontal activity above the continental United States, the location of NO/sub x/ plumes was explained with maps of convective influence. In another case, NO/sub x/ seems to have been produced by lightning in a marine thunderstorm over the eastern Atlantic. Lightning activity triggered over the warm Gulf Stream is found to be an important source for the regional upper tropospheric NO/sub x/ budget, at least for the time period considered. With a method that the authors call "lightning tracing" the authors show for the first time that (in some cases) the number of lightning flashes, accumulated along back trajectories, was proportional to the NO/sub x/ concentrations observed several hundred kilometers downwind of the anvil outflows }, keywords={ air pollution atmospheric composition lightning nitrogen compounds stratosphere troposphere atmosphere stratosphere chemical composition air pollution troposphere tropopause convection lightning POLINAT 2 North Atlantic Flight Corridor AD 1997 United States USA Subsonic Assessment Ozone and Nitrogen Oxide Experiment SONEX Nitrogen Oxides and Ozone Along Air Routes NOXAR patchy occurrence NO/sub x/ plume back trajectory anvil outflow NO NO$_2$ O/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SchumannFeb00, author={Schumann, U. and Schlager, H. and Arnold, F. and Ovarlez, J. and Kelder, H. and Hov, O. and Hayman, G. and Isaksen, I.S.A. and Staehelin, J. and Whitefield, P.D.}, title={ Pollution from aircraft emissions in the North Atlantic flight corridor: overview on the POLINAT projects }, journal={Journal of Geophysical Research}, volume={105}, number={D3}, year={2000}, month={Feb}, pages={3605-31}, abstract={ The Pollution From Aircraft Emissions in the North Atlantic Flight Corridor (POLINAT) projects were undertaken to investigate the impact of aircraft engine exhaust emissions on the state of the atmosphere in the North Atlantic flight corridor. Changes in the composition of the lower stratosphere and upper troposphere from aircraft emissions are identified from combined measurements and model analyses. Measurements were performed using the Deutsches Zentrum fur Luft- und Raumfahrt Falcon research aircraft and a Swissair B-747 over the North Atlantic covering the altitude range 6 to 13 km in November 1994 and June/July 1995 and from August to November 1997. The measurements include those of nitrogen oxides, nitrous and nitric acids, sulfur dioxide, sulfuric acid, acetone, carbon dioxide, ozone, water vapor, carbon monoxide, aerosols, and meteorological parameters. The atmospheric composition was found to be highly variable, and emissions from sources at the surface or from lightning discharges also contribute strongly to the nitrogen oxides abundance and ozone formation. Contributions from aircraft emissions have been measured and identified in single and multiple plumes of several hours ages, and accumulation of such nitrogen oxides and particles emissions can be identified under certain conditions in and downstream of the flight corridor region. Acetone was found at high mixing ratios. The global and regional models predict ozone increases of 3 to 6% by current air traffic at the flight corridor altitude north of 30 degrees N, in agreement with previous model analyses but too small to be measurable. In autumn, the upper troposphere is often humid with water vapor concentration far above ice saturation, providing conditions for persistent contrails }, keywords={ air pollution atmospheric composition stratosphere troposphere atmosphere troposphere stratosphere chemical composition air pollution aircraft aircraft emissions North Atlantic flight corridor POLINAT project research programme exhaust AD 1994 AD 1995 AD 1997 ozone acetone aerosol 6 to 13 km HNO/sub 3/ SO$_2$ H$_2$SO/sub 4/ CO$_2$ O/sub 3/ CO }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ZhangMar00, author={Zhang, R. and Sanger, N.T. and Orville, R.E. and Xuexi Tie and Randel, W. and Williams, E.R.}, title={ Enhanced NO/sub x/ by lightning in the upper troposphere and lower stratosphere inferred from the UARS global NO$_2$ measurements }, journal={Geophysical Research Letters}, volume={27}, number={5}, year={2000}, month={Mar}, pages={685-8}, abstract={ This paper reveals a possible connection between lightning activity and the UARS NO$_2$ data on a global scale. NO$_2$ measured by the Halogen Occultation Experiment (HALOE) on the Upper Atmosphere Research Satellite (UARS) is analyzed for the entire year of 1993 and compared to the seasonal and global lightning distributions inferred from the Optical Transient Detector (OTD). The results suggest a link between lightning activity and observed high levels of NO$_2$ in the upper troposphere and lower stratosphere. Enhanced NO$_2$ mixing ratios significantly above the background level are consistently found in areas of elevated lightning activity. This relation is strongest in the tropical regions during the summer and spring months of the Northern and Southern Hemispheres. Moreover, the results show that background levels of NO$_2$ mixing ratios generally correspond to areas of little or no lightning activity }, keywords={ atmospheric composition lightning nitrogen compounds stratosphere troposphere chemical composition NO/sub x/ enhancement lightning upper troposphere lower stratosphere UARS global observations global scale Halogen Occultation Experiment HALOE AD 1993 lightning activity troposphere stratosphere tropical region summer season spring NO$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ArmstrongMar00, author={Armstrong, R.A. and Suszcynsky, D.M. and Lyons, W.A. and Nelson, T.E.}, title={ Multi-color photometric measurements of ionization and energies in sprites }, journal={Geophysical Research Letters}, volume={27}, number={5}, year={2000}, month={Mar}, pages={653-6}, abstract={ Recent time-resolved multi-color photometric data obtained on one class of lightning-related transient upper-atmospheric electromagnetic events called sprites have confirmed an impulsive ionization emission during the sprite initiation. Data have also been obtained on some sprites which do not exhibit observable tendrils and which exhibit ionization emission that, if present, is below the authors' detection limit. This suggests that some sprite events exhibit strong ionization while others do not. These results indicate that conditions causing sprite optical emissions are highly variable }, keywords={ airglow atmospheric ionisation atmospheric radiation lightning mesosphere stratosphere thermosphere stratosphere mesosphere thermosphere upper atmosphere middle atmosphere optical emission multicolor photometry ionization sprite time-resolved observation temporal variation lightning-related impulsive ionization emission }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PaskoFeb00, author={Pasko, V.P. and Inan, U.S. and Bell, T.F.}, title={ Fractal structure of sprites }, journal={Geophysical Research Letters}, volume={27}, number={4}, year={2000}, month={Feb}, pages={497-500}, abstract={ A large scale model of sprites based on a phenomenological probabilistic approach to modeling of streamer corona discharges is developed. The model utilizes the experimentally documented macroscopic properties of positive and negative streamer coronas in air and allows a realistic determination of the propagation of multiple breakdown branches in a self-consistent electric field. The model results reproduce the large scale volumetric shapes of sprites, agree with the experimentally documented thundercloud charge moment changes in sprites producing cloud to ground lightning discharges (CGs), and demonstrate fundamental asymmetries between sprites generated by CGs of positive and negative polarity }, keywords={ fractals ionospheric disturbances lightning thunderstorms fractal structure sprites streamer corona discharges macroscopic properties multiple breakdown branches self-consistent electric field large scale volumetric shapes thundercloud charge moment changes cloud to ground lightning discharges }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{FullekrugFeb00, author={Fullekrug, M. and Constable, S.}, title={ Global triangulation of intense lightning discharges }, journal={Geophysical Research Letters}, volume={27}, number={3}, year={2000}, month={Feb}, pages={333-6}, abstract={ A global network of three electromagnetic measurement instruments is used to simultaneously record time series of globally observable extremely-low-frequency (ELF) magnetic field disturbances which propagate with little attenuation around the globe within the Earth-ionosphere cavity. The triangulation of individual lightning flashes results in a picture of the temporal evolution of intense lightning discharge occurrences on the planetary scale during April 1998. The lightning flash charge moments are calculated with the short pulse approximation of the normal mode expansion. The majority of the triangulated lightning discharges exhibit charge moments with a potential to excite mesospheric sprites and À5-20% may account for air breakdown at sprite altitudes in À50-70 km height }, keywords={ Earth-ionosphere waveguide lightning mesosphere global triangulation network intense lightning discharges sprite altitudes EM measurement instruments globally observable ELF magnetic field disturbances Earth-ionosphere cavity temporal evolution AD 1998 04 lightning flash charge moments short pulse approximation normal mode expansion triangulated lightning discharges mesospheric sprite excitation air breakdown 4 to 200 Hz }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Barrington-LeighDec99, author={Barrington-Leigh, C.P. and Inan, U.S. and Stanley, M. and Cummer, S.A.}, title={ Sprites triggered by negative lightning discharges }, journal={Geophysical Research Letters}, volume={26}, number={24}, year={1999}, month={Dec}, pages={3605-8}, abstract={ High altitude air breakdown, manifested as "red sprites", is reported in close association with negative cloud-to-ground lightning (-CG) on at least two occasions above an unusual storm on August 29, 1998. Data from high speed photometry, low-light-level video, and receivers of lightning electromagnetic signatures in the frequency range 10 Hz to 20 kHz are used to establish the association and indicate that the causative -CG discharges effected unusually large vertical charge moment changes ( Delta M/sub Qv/) of up to 1550 C.km in 5 ms. The existence of sprites caused by -CG events, rather than the regularly associated +CG events, has immediate implications for sprite models and observations }, keywords={ atmospheric electricity ionospheric disturbances lightning photometry negative lightning discharges sprite triggering high altitude air breakdown red sprites negative cloud-to-ground lightning AD 1998 08 29 high speed photometry low-light-level video lightning EM signatures vertical charge moment changes sprite models sprite observations N Gulf of California Mexico 10 Hz to 20 kHz }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SmyshlyaevNov99, author={Smyshlyaev, S.P. and Geller, M.A. and Yudin, V.A.}, title={ Sensitivity of model assessments of high-speed civil transport effects on stratospheric ozone resulting from uncertainties in the NO/sub x/ production from lightning }, journal={Journal of Geophysical Research}, volume={104}, number={D21}, year={1999}, month={Nov}, pages={26401-17}, abstract={ Lightning NO/sub x/ production is one of the most important and most uncertain sources of reactive nitrogen in the atmosphere. To examine the role of NO/sub x/ lightning production uncertainties in supersonic aircraft assessment studies, the authors have done a number of numerical calculations with the State University of New York at Stony Brook-Russian State Hydrometeorological Institute of Saint-Petersburg two-dimensional model. The amount of nitrogen oxides produced by lightning discharges was varied within its quoted uncertainty from 2 to 12 Tg N/yr. Different latitudinal, altitudinal, and seasonal distributions of lightning NO/sub x/ production were considered. Results of these model calculations show that the assessment of supersonic aircraft impacts on the ozone layer is very sensitive to the strength of NO/sub x/ production from lightning. The high-speed civil transport produced NO/sub x/ leads to positive column ozone changes for lightning NO/sub x/ production less than 4 Tg N/yr, and to total ozone decrease for lightning NO/sub x/ production more than 5 Tg N/yr for the same NO/sub x/ emission scenario }, keywords={ aircraft atmospheric chemistry atmospheric composition lightning nitrogen compounds ozone stratosphere high-speed civil transport effects stratospheric ozone lightning NO/sub x/ production reactive nitrogen sources supersonic aircraft numerical calculations nitrogen oxides lightning discharges latitudinal distributions altitudinal distributions seasonal distributions ozone layer SUNY-SPB 2D model O/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{NunnNov99, author={Nunn, D. and Rodger, C.J.}, title={ Modeling the relaxation of red sprite plasma }, journal={Geophysical Research Letters}, volume={26}, number={21}, year={1999}, month={Nov}, pages={3293-6}, abstract={ Red sprites consist of multiple ionised columns extending above a thunderstorm from À30 km to À90 km. Electron densities in these columns are very much larger than the ambient background, perhaps fives orders of magnitude at 70 km. These highly ionized structures cause observable perturbations in subionospheric VLF transmissions known as "VLF sprites". Three models of initial sprite electron density are considered, and using a realistic ionization relaxation model the time dependence of electron density is derived. A 3D Born propagation code of is used to compute the time profile of a VLF sprite. Two profiles show good agreement with the time signature experimentally observed, in that scattered amplitude and phase decrease logarithmically with time. These simulations provide insight into the nature and structure of sprite columns, and indicate an additional constraint which should be applied to red sprite creation models }, keywords={ atmospheric electromagnetic wave propagation atmospheric ionisation ionosphere ionospheric electromagnetic wave propagation lightning mesosphere thermosphere mesosphere thermosphere lightning middle atmosphere upper atmosphere plasma relaxation red sprite multiple ionised column thunderstorm electron density highly ionized structure ionization relaxation model 3D Born propagation code VLF sprite radiowave propagation sprite column 30 to 90 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LevyNov99, author={Levy, H., II and Moxim, W.J. and Klonecki, A.A. and Kasibhatla, P.S.}, title={ Simulated tropospheric NO/sub x/: its evaluation, global distribution and individual source contributions }, journal={Journal of Geophysical Research}, volume={104}, number={D21}, year={1999}, month={Nov}, pages={26279-306}, abstract={ Using the 11-level Geophysical Fluid Dynamics Laboratory global chemical transport model, we simulate global tropospheric fields of NO/sub x/, peroxyacetyl nitrate (PAN), HNO/sub 3/, and NO/sub y/, as well as the deposition of nitrate, extensively evaluate them against available observations of individual natural and anthropogenic sources. The patterns and magnitudes of simulated and observed HNO/sub 3/ wet deposition are generally in good agreement around the globe. Scatterplots of model simulations versus aircraft observations for NO/sub x/ and NO/sub y/ find À50% of the points within +or-25%, find À75% within +or-50%, and show no systematic global biases. Both simulated and observed vertical profiles have similar shapes with high levels (À1 ppbv or greater) in the polluted boundary layer (BL), very low values in the remote BL, and values increasing from the middle to the upper troposphere. Simulated NO/sub y/, HNO/sub 3/, and NO/sub x/+PAN are also in good agreement with extensive lower free tropospheric (FT) observations made at Mauna Loa Observatory. In general, the level of agreement between simulation and observation is as good as the agreement between separate, but simultaneous, observations of NO, NO/sub x/ or NO/sub y/. As previous studies have shown, fossil fuel combustion and biomass burning control NO/sub x/ levels in most of the lower half of the troposphere with a significant contribution from biogenic emissions. The exceptions are the remote low-NO/sub x/ regions where BL and FT sources make comparable contributions. Unlike most previous studies, we find that the much smaller in situ FT sources generally dominate in the upper half of the troposphere. Lightning dominates in the tropics and summertime midlatitudes, and stratospheric injection is the major source in the summer high latitudes. The exception is transported emissions from fossil fuel combustion, which dominate in winter high latitudes. Though seldom dominant, aircraft emissions do have sig }, keywords={ air pollution atmospheric composition atmospheric movements nitrogen compounds troposphere tropospheric NO/sub x/ global distribution source contributions 11-level Geophysical Fluid Dynamics Laboratory global chemical transport model peroxyacetyl nitrate PAN HNO/sub 3/ NO/sub y/ nitrate deposition anthropogenic sources NO/sub x/ vertical profiles polluted boundary layer Mauna Loa Observatory fossil fuel combustion biomass burning control }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{CummerOct99, author={Cummer, S.A. and Stanley, M.}, title={ Submillisecond resolution lightning currents and sprite development: observations and implications }, journal={Geophysical Research Letters}, volume={26}, number={20}, year={1999}, month={Oct}, pages={3205-8}, abstract={ We analyze synchronized high speed video images and ELF-VLF radio emissions from 11 sprite clusters observed on 6 October 1997. Quantitative analysis shows that vertical lightning charge moment changes of 150-1100 C.km occurred before the optical emissions reached their peak with delays of 2-11 ms from the lightning discharge. This threshold unexpectedly decreases with increasing delay from parent lightning to peak emissions. We also find that sprite charge moment change and minimum sprite altitude are not well correlated with the vertical charge moment change in the parent discharge. These observations do not agree well with present sprite generation models, and we suggest that streamer development and horizontal lightning charge motion can play a significant role in sprite generation }, keywords={ atmospheric electricity atmospherics ionospheric disturbances lightning submillisecond resolution lightning currents sprite development high speed video images ELF-VLF radio emissions 6 October 1997 vertical lightning charge moment changes optical emissions minimum sprite altitude vertical charge moment change sprite generation models horizontal lightning charge motion AD 1997 10 06 }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{StanleyOct99, author={Stanley, M. and Krehbiel, P. and Brook, M. and Moore, C. and Rison, W. and Abrahams, B.}, title={ High speed video of initial sprite development }, journal={Geophysical Research Letters}, volume={26}, number={20}, year={1999}, month={Oct}, pages={3201-4}, abstract={ High speed video of sprites show that they are typically initiated at an altitude of about 75 km and usually develop simultaneously upwards and downwards from the point of origin with an initial columniform shape. The initial development of sprites appears to be dominated by corona streamers with velocities in excess of 10/sup 7/ m/s. Many of the observed characteristics are consistent with a conventional breakdown mechanism for both sprite initiation and initial sprite development }, keywords={ atmospheric electricity ionospheric disturbances high speed video initial sprite development columniform shape development corona streamers velocities breakdown mechanism 75 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ThompsonOct99, author={Thompson, A.M. and Sparling, L.C. and Kondo, Y. and Anderson, B.E. and Gregory, G.L. and Sachse, G.W.}, title={ Perspectives on NO, NO/sub y/ and fine aerosol sources and variability during SONEX }, journal={Geophysical Research Letters}, volume={26}, number={20}, year={1999}, month={Oct}, pages={3073-6}, abstract={ Distributions of upper tropospheric tracer data on each of the 14 science flights of SONEX (SASS [Subsonics Assessment] Ozone and Nitrogen Oxides Experiment) provide a statistical overview of NO, NO/sub y/ and fine aerosol variability during SONEX (an aircraft mission conducted in October and November 1997). The wide range of variability of NO from all sources provides a perspective on the aircraft perturbation. Background distributions of NO/sub y/ are somewhat elevated inside flight corridors relative to outside; fine aerosol and NO/NO/sub y/ in and out of corridors are similar. The potential vorticity of air sampled during SONEX is low relative to the NAFC (North Atlantic Flight Corridor) as a whole, due either to advection of lower latitude air into the corridor or biases in sampling to avoid the stratosphere. High NO/NO/sub y/ (>0.4) from fresh lightning and aircraft sources was usually associated with pv much lower than the NAFC as a whole. Air masses identified as tropospheric by a low ozone criterion nevertheless have high pv, a marker for stratospheric air. Thus, stratospheric and surface sources also contribute to overall variability. A statistically robust assessment of the relative aircraft NO contribution during SONEX, based on data alone, is unlikely, given the mixture of other NO sources within which the aircraft signal is embedded. This underscores the need for more data and modeling studies }, keywords={ aerosols air pollution aircraft nitrogen compounds NO/sub y/ fine aerosol variability SONEX upper tropospheric tracer data Subsonics Assessment SASS Ozone and Nitrogen Oxides Experiment aircraft perturbation NO/NO/sub y/ potential vorticity North Atlantic Flight Corridor fresh lightning aircraft source NO }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LehtinenNov99, author={Lehtinen, N.G. and Bell, T.F. and Inan, U.S.}, title={ Monte Carlo simulation of runaway MeV electron breakdown with application to red sprites and terrestrial gamma ray flashes }, journal={Journal of Geophysical Research}, volume={104}, number={A11}, year={1999}, month={Nov}, pages={24699-712}, abstract={ A three-dimensional Monte Carlo model of the uniform relativistic runaway electron breakdown in air in the presence of static electric and magnetic fields is used to calculate electron distribution functions, avalanche rates, and the direction and velocity of avalanche propagation. The authors also derive the conditions required for an electron with a given momentum to start an avalanche in the absence of a magnetic field. The results are compared to previously developed kinetic and analytical models and their own analytical estimates, and it is concluded that the rates used in many early models [e.g., Lehtinen et al., 1997; Taranenko and Roussel-Dupre, 1996; Yukhimuk et al., 1998; Roussel-Dupre et al., 1998] are overestimated by a factor of À10. The Monte Carlo simulation results are applied to a fluid model of runaway electron beams in the middle atmosphere accelerated by quasi-electrostatic fields following a positive lightning stroke. In particular, the authors consider the case of lightning discharges which drain positive charge from remote regions of a laterally extensive (>100 km) thundercloud, using a Cartesian two-dimensional model. The resulting optical emission intensities in red sprites associated with the runaway electrons are found to be negligible compared to the emissions from thermal electrons heated in the conventional type of breakdown. The calculated gamma ray flux is of the same order as the terrestrial gamma ray flashes observed by the Burst and Transient Source Experiment detector on the Compton Gamma Ray Observatory }, keywords={ atmospheric electricity atmospheric radiation gamma-rays lightning mesosphere mesosphere middle atmosphere electric discharge electricity electric breakdown model Monte Carlo simulation runaway MeV electron breakdown red sprite gamma ray flash gamma-ray emission lightning three-dimensional model gamma-rays relativistic runaway electron distribution function avalanche rate propagation velocity propagation direction quasi-electrostatic field optical emission }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Chakravarty97, author={Chakravarty, S.C. and Gupta, S.P. and Chandrasekaran, S.}, title={ Middle atmospheric electrodynamics at low latitude over India }, journal={Advances in Space Research}, volume={20}, number={11}, year={1997}, month={}, pages={2181-9}, abstract={ Low latitude middle atmospheric electrodynamics has a number of interesting features such as low flux of cosmic rays due to high cut-off rigidities, higher solar electromagnetic radiation intensities and mesospheric ionisation, large scale convection and wide-spread lightning phenomena, higher tropopause level and special characteristics associated with the equatorial electrojet. These special features play a vital role in governing the electrodynamics of the global middle atmosphere. In India, a well coordinated multi-institutional campaign was organised under MAP (middle atmosphere programme) to carry out balloon and rocket borne experiments to measure electrical parameters of the middle atmosphere. The measured parameters include electron/ion densities and mobilities, polar ion conductivities and electric fields. The experiments were carried out during different seasons and solar activity epochs. The results obtained from these investigations are discussed and compared with similar measurements over the middle latitude stations to assess the integrated effect of the global atmospheric electrodynamic phenomenon }, keywords={ atmospheric electricity atmospheric temperature cosmic ray interactions D-region electric fields electrodynamics electron density mesosphere stratosphere wind atmospheric electrodynamics low latitude middle atmosphere electron densities ion densities ion mobilities ion conductivities electric fields different seasons different solar activity epochs stratosphere middle latitude balloon campaigns temporal variations vertical profiles ion chemical scheme cosmic ray ion production rates mesosphere rocket sounding zonal wind meridional wind D region atmospheric temperature wave like features India }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Chakravarty97, author={Chakravarty, S.C. and Gupta, S.P. and Chandrasekaran, S.}, title={ Middle atmospheric electrodynamics at low latitude over India }, journal={Advances in Space Research}, volume={20}, number={11}, year={1997}, month={}, pages={2181-9}, abstract={ Low latitude middle atmospheric electrodynamics has a number of interesting features such as low flux of cosmic rays due to high cut-off rigidities, higher solar electromagnetic radiation intensities and mesospheric ionisation, large scale convection and wide-spread lightning phenomena, higher tropopause level and special characteristics associated with the equatorial electrojet. These special features play a vital role in governing the electrodynamics of the global middle atmosphere. In India, a well coordinated multi-institutional campaign was organised under MAP (middle atmosphere programme) to carry out balloon and rocket borne experiments to measure electrical parameters of the middle atmosphere. The measured parameters include electron/ion densities and mobilities, polar ion conductivities and electric fields. The experiments were carried out during different seasons and solar activity epochs. The results obtained from these investigations are discussed and compared with similar measurements over the middle latitude stations to assess the integrated effect of the global atmospheric electrodynamic phenomenon }, keywords={ atmospheric electricity atmospheric temperature cosmic ray interactions D-region electric fields electrodynamics electron density mesosphere stratosphere wind atmospheric electrodynamics low latitude middle atmosphere electron densities ion densities ion mobilities ion conductivities electric fields different seasons different solar activity epochs stratosphere middle latitude balloon campaigns temporal variations vertical profiles ion chemical scheme cosmic ray ion production rates mesosphere rocket sounding zonal wind meridional wind D region atmospheric temperature wave like features India }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{RodgerAug99, author={Rodger, C.J.}, title={ Red sprite, upward lightning, and VLF perturbations }, journal={Reviews of Geophysics}, volume={37}, number={3}, year={1999}, month={Aug}, pages={317-36}, abstract={ In the last decade there has been a great deal of interest in the detection and understanding of phenomena occurring above active thunderstorms. The discovery of the optical phenomena now termed "red sprites" is discussed, along with the properties that have been experimentally determined. Areas of disagreement between experimentalists are pointed out. Other optical and electromagnetic phenomena associated with red sprites are presented. These include blue jets, transionospheric pulse pairs, and gamma ray flashes. Particular attention is given to the work on perturbations on very low-frequency radio wave transmissions ("VLF sprites"), which has provided estimates of the electrical properties of sprites. Research into activity above thunderstorms will continue to lead to a greater understanding of the coupling between thunderstorms in the troposphere to the stratosphere, mesosphere, ionosphere, and beyond }, keywords={ airglow atmospheric electromagnetic wave propagation bibliographies ionosphere ionospheric disturbances ionospheric electromagnetic wave propagation lightning mesosphere reviews stratosphere thermosphere thunderstorms red sprite lightning middle atmosphere atmosphere thermosphere upper atmosphere upward lightning VLF perturbations thunderstorm optical phenomena blue jet transionospheric pulse pair ionospheric disturbance ionosphere gamma ray flash very low-frequency radio wave transmission VLF sprite radiowave propagation troposphere stratosphere mesosphere }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LiuAug99, author={Liu, S.C. and Yu, H. and Ridley, B. and Wang, Y. and Davis, D.D. and Kondo, Y. and Koike, M. and Anderson, B.E. and Vay, S.A. and Sachse, G.W. and Gregory, G.L. and Fuelburg, H. and Thompson, A. and Singh, H.}, title={ Sources of reactive nitrogen in the upper troposphere during SONEX }, journal={Geophysical Research Letters}, volume={26}, number={16}, year={1999}, month={Aug}, pages={2441-4}, abstract={ The relationship among NO/sub y/, O/sub 3/, N$_2$O, ultra-fine condensation nuclei (CN), and other trace gases in the upper troposphere (UT) and lower stratosphere (LS) observed during SONEX are analyzed with the goal to identify and quantify the sources of NO/sub y/ in the UT. We use N$_2$O to separate upper tropospheric air from stratospheric influenced air and focus our analysis on the former. The distributions of NO/sub y/ and O/sub 3/ show remarkable similarity when they are plotted as a function of N$_2$O. The only difference between NO/sub y/ and O/sub 3/ is found in upper tropospheric air where a large number of data points have high values of both NO/sub y/ and the NO/sub y//O/sub 3/ ratio. Major sources contributing to these high NO/sub y/ values are found to be emissions from lightning and surface sources transported to the UT by convection }, keywords={ atmospheric composition nitrogen compounds troposphere reactive nitrogen upper troposphere SONEX NO/sub y/ ultra-fine condensation nuclei trace gases lower stratosphere lightning surface sources convection O/sub 3/ N$_2$O }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HuangJul99, author={Huang, E. and Williams, E. and Boldi, R. and Heckman, S. and Lyons, W. and Taylor, M. and Nelson, T. and Wong, C.}, title={ Criteria for sprites and elves based on Schumann resonance observations }, journal={Journal of Geophysical Research}, volume={104}, number={D14}, year={1999}, month={Jul}, pages={16943-64}, abstract={ Ground flashes with positive polarity associated with both sprites and elves excite the Earth's Schumann resonances to amplitudes several times greater than the background resonances. Theoretical predictions for dielectric breakdown in the mesosphere are tested using ELF methods to evaluate vertical charge moments of positive ground flashes. Comparisons of the measured time constants for lightning charge transfer with the electrostatic relaxation time at altitudes of nighttime sprite initiation (50-70 km) generally validate the electrostatic assumption in predictions made initially by Wilson (1925). The measured charge moments (QdS=200-2000 C-km) are large in comparison with ordinary negative lightning but are generally insufficient to account for conventional air breakdown at sprite altitudes. The measured charge moments, however, are sufficient to account for electron runaway breakdown, and the long avalanche length in this mechanism also accounts for the exclusive association of sprites with ground flashes of positive polarity. The association of elves with large peak currents (50-200 kA) measured by the National Lightning Detection Network in a band pass beyond the Schumann resonance range is consistent with an electromagnetic pulse mechanism for these events }, keywords={ Earth-ionosphere waveguide lightning mesosphere sprites elves Schumann resonance observations mesospheric dielectric breakdown ELF methods vertical charge moments positive ground flashes measured time constants lightning charge transfer electrostatic relaxation time nighttime sprite initiation air breakdown electron runaway breakdown avalanche length peak currents National Lightning Detection Network EM pulse mechanism }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{StithJul99, author={Stith, J. and Dye, J. and Ridley, B. and Laroche, P. and Defer, E. and Baumann, K. and Hubler, G. and Zerr, R. and Venticinique, M.}, title={ NO signatures from lightning flashes }, journal={Journal of Geophysical Research}, volume={104}, number={D13}, year={1999}, month={Jul}, pages={16081-9}, abstract={ In situ measurements of cloud properties, NO, and other trace gases were made in active thunderstorms by two research aircraft. Concurrent measurements from a three-dimensional (3D) VHF interferometer and the 2D National Lightning Detection Network were used to determine lightning frequency and location. The CHILL Doppler radar and the NOAA-WP-3D Orion X band Doppler radar were also used to measure storm characteristics. Two case studies from the (STERAO) Stratosphere-Troposphere Experiments: Radiation, Aerosols, and Ozone project in northeastern Colorado during the summer of 1996 are presented. Narrow spikes (0.11-0.96 km across), containing up to 19 ppbv of NO, were observed in the storms. Most were located in or downwind of electrically active regions where the NO produced by lightning would be expected. However, it was difficult to correlate individual flashes with NO spikes. A simple model of the plume of NO from lightning is used to estimate NO production from the mean mixing ratio measured in these spikes. The estimates range from 2.0*10/sup 20/ to 1.0*10/sup 22/ molecules of NO per meter of flash length }, keywords={ atmospheric composition clouds lightning nitrogen compounds thunderstorms atmosphere troposphere chemical composition thundercloud cloud thunderstorm lightning trace gas United States USA STERAO Colorado summer AD 1996 NO }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PaskoMay99, author={Pasko, V.P. and Inan, U.S. and Bell, T.F.}, title={ Mesospheric electric field transients due to tropospheric lightning discharges }, journal={Geophysical Research Letters}, volume={26}, number={9}, year={1999}, month={May}, pages={1247-50}, abstract={ A physical picture and quantitative two-dimensional electromagnetic modeling of mesospheric electric field transients produced by cloud-to-ground (CG) lightning discharges with short duration currents (<0.5 ms) are presented. The range of applicability of existing quasi-electrostatic models of sprites and the physical conditions under which relatively weak CG lightning discharges (thundercloud charge moment changes less than 50 C *10 km) may initiate sprites are discussed in the context of experimental findings }, keywords={ atmospheric electricity lightning mesosphere mesospheric electric field transients tropospheric lightning discharges 2D EM modelling cloud-to-ground lightning discharges short duration currents quasi-electrostatic models sprites thundercloud charge moment changes }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{VeronisJun99, author={Veronis, G. and Pasko, V.P. and Inan, U.S.}, title={ Characteristics of mesospheric optical emissions produced by lightning discharges }, journal={Journal of Geophysical Research}, volume={104}, number={A6}, year={1999}, month={Jun}, pages={12645-56}, abstract={ A new 2D cylindrically symmetric EM model of the lightning-ionosphere interaction includes effects of both the lightning radiated EM pulses (EMP) and the quasi-electrostatic (QE) fields, thus allowing effective studies of lightning-ionosphere interactions on time scales ranging from several microseconds to tens of milliseconds. The temporal and spatial evolution of the electric field, lower ionospheric electron density, and optical emissions calculated with the new model are used to investigate theoretically the effects of the lightning return stroke current waveform and of the observational geometry on the optical signals observed with a photometer. For typical lightning discharges of À100 mu s duration the ionospheric response is dominated by the EMP-induced heating leading to the highly transient and laterally expanding optical flashes known as elves. The optical signal characteristics are found to be highly sensitive to both the observational geometry and the current waveform. The onset delay with respect to the lightning discharge, the duration, and the peak magnitude of optical emissions are highly dependent on the elevation and azimuth angles of field of view of individual photometric pixels. The shape of the optical signal clearly reflects the source current waveform. For a waveshape with risetime of À50 mu s or longer a double-pulse shape of the photometric signal is observed. For cloud to ground lightning discharges of À1 ms duration removing substantial amount of charge, heating and ionization changes induced by the QE field lead to the mesospheric luminous glows with lateral extent <100 km, referred to as sprites }, keywords={ atmospheric radiation atmospheric temperature electromagnetic pulse electron density ionospheric disturbances lightning mesosphere mesospheric optical emissions lightning discharges 2D cylindrically symmetric electromagnetic model lightning-ionosphere interaction EM pulses quasi-electrostatic fields time scales temporal evolution spatial evolution lower ionospheric electron density lightning return stroke current waveform observational geometry EMP-induced heating optical flashes elves onset delay duration source current waveform risetime double-pulse shape photometric signal ionization changes }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Farag98, author={Farag, A.S. and Shwehdi, M. and Belhadj, C.A. and Cheng, T.C. and Penn, D.}, title={ Air terminations for lightning protection of structures }, booktitle={1998 Annual Report Conference on Electrical Insulation and DielectricPhenomena (Cat. No.98CH36257)}, volume={}, number={}, year={1998}, month={}, pages={67-71 vol. 1}, abstract={ The most recent knowledge on physics of discharges derived from researchers on long air gap sparks is considered to assess the conditions for the inception of upward leaders from earthed structures. The protection angles of rods or wires are determined by means of simplified physical models of lightning which takes into account the electric field on earthed objects. Shielding criteria is then defined which takes into account the risk of damage of the protected structure related with the statistical distributions of the lightning parameters involved in the phenomenon. Spacing between air terminations and protected structure to withstand induced voltage stresses is examined. Thermal effects at the impact point are summarized and practical sizing of air-termination elements are given }, keywords={ air gaps lightning protection air termination lightning protection spark discharge air gap electric field shielding leader earthed structure rod wire }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PetrovApr99, author={Petrov, N.I. and Petrova, G.N.}, title={ Physical mechanisms for the development of lightning discharges between a thundercloud and the ionosphere }, journal={Zhurnal Tekhnicheskoi Fiziki}, volume={69}, number={4}, year={1999}, month={Apr}, pages={134-7}, abstract={ An investigation is made of the influence of changes in atmospheric pressure with altitude and the thundercloud geometry on the development of lightning propagating upward to the ionosphere. It is shown that the mechanism for the development of high-altitude lightning does not differ from that for the formation and propagation of ordinary lightning between a thundercloud and the ground. It is established that high-altitude lightning forms as a result of a reduction in pressure with altitude and can only take place from thunderclouds located at high altitudes }, keywords={ lightning mesosphere stratosphere thermosphere development physical mechanism lightning upward discharge thermosphere mesosphere middle atmosphere upper atmosphere streamer sprite stratosphere atmospheric pressure thundercloud geometry high-altitude high-altitude lightning }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MohamedDec98, author={Mohamed, M.M. and Shalaby, E.A. and Ghatass, Z.F. and Naim, M.A. and El-Raey, M.}, title={ Three-phase plasma arc with conical configuration for atomic emission spectroscopy }, journal={Indian Journal of Pure and Applied Physics}, volume={36}, number={12}, year={1998}, month={Dec}, pages={719-28}, abstract={ Electrical schematics, construction details, and performance examples for a modified three-phase argon plasma arc (TPAPA) are given. A new three carbon electrodes conical configuration is developed as an alternative to the previously published three tungsten electrodes argon plasma torch. Introduction of the aerosol is through an injection tube with an orifice of 1 mm located below circularly symmetric upward propagating plasma, where aerosol is completely surrounded by the plasma. Spectroscopic measurements are made in the plume above the plane of the three-electrode surface. Measurements reported include: arc discharge spectral and positional stability and reproducibility, background emission from the plume, standard calibration curves, and detection limits for some elements. A comparison has also been made between the conical configuration and the plasma torch }, keywords={ arcs (electric) atomic emission spectroscopy calibration electrodes plasma applications spectrometer accessories three-phase plasma arc conical configuration atomic emission spectroscopy electrical schematics three carbon electrodes conical configuration aerosol injection tube orifice circularly symmetric upward propagating plasma three-electrode surface arc discharge spectral stability arc discharge positional stability background emission standard calibration curves detection limits plume plasma torch reproducibility }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Barrington-LeighMar99, author={Barrington-Leigh, C.P. and Inan, U.S.}, title={ Elves triggered by positive and negative lightning discharges }, journal={Geophysical Research Letters}, volume={26}, number={6}, year={1999}, month={Mar}, pages={683-6}, abstract={ Optical flashes in the lower ionosphere due to the transient heating caused by lightning electromagnetic pulses (EMP) are unambiguously identified with the Fly's Eye photometric array. Data from a thunderstorm over Mexico recorded at Langmuir Laboratory on August 27 1997 demonstrate that relatively common negative cloud-to-ground lightning is a previously unrecognized major cause of elves. The spatial extent of the transient heating is shown optically to be typically at least 200-700 km laterally, indicating the possibility for accumulation of ionization effects produced by successive flashes within large nighttime thunderstorm systems. One especially bright event suggests that temporal fine-structure in the causative very low frequency EMP can manifest itself in the photometric record of elves }, keywords={ ionosphere lightning mesosphere thermosphere elf elves optical emission upper atmosphere thermosphere middle atmosphere mesosphere lightning triggered negative lightning discharge positive lightning lightning electric discharge optical flash lower ionosphere transient heating lightning electromagnetic pulse EMP thunderstorm storm Mexico AD 1997 08 27 negative cloud-to-ground lightning cause spatial extent ionization effec temporal fine-structure }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{YukhimukMar99, author={Yukhimuk, V. and Roussel-Dupre, R.A. and Symbalisty, E.M.D.}, title={ On the temporal evolution of red sprites: runaway theory versus data }, journal={Geophysical Research Letters}, volume={26}, number={6}, year={1999}, month={Mar}, pages={679-82}, abstract={ The results of numerical simulations of red sprite discharges, namely the temporal evolutions of optical emissions, are presented and compared with observations. The simulations are done using the recently recalculated runaway avalanche rates. The temporal evolution of these simulations is in good agreement with ground-based photometer and CCD TV camera observations of red sprites. The authors' model naturally explains the "hairline" of red sprites as a boundary between the region where the intensity of optical emissions associated with runaway breakdown has a maximum and the region where the intensity of optical emissions caused by conventional breakdown and ambient electron heating has a maximum. Other important characteristics of the simulated sprite such as color, shape, altitude, and intensity are in agreement with the observations as well. The authors also present for the first time simulations of red sprites with a daytime conductivity profile }, keywords={ lightning mesosphere stratosphere thermosphere stratosphere mesosphere thermosphere middle atmosphere upper atmosphere electrical discharge lightning optical emission temporal evolution red sprite numerical simulation runaway avalanche rate runaway theory model hairline runaway breakdown color colour shape altitude intensity daytime conductivity profile }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MilikhFeb99, author={Milikh, G. and Valdivia, J.A.}, title={ Model of gamma ray flashes due to fractal lightning }, journal={Geophysical Research Letters}, volume={26}, number={4}, year={1999}, month={Feb}, pages={525-8}, abstract={ A model of gamma -ray flashes is presented. The model relies upon a horizontal fractal lightning discharge, which generates the electromagnetic pulses that produce the stochastic electron runaway discharge in the stratosphere. The model computes the flux and energy spectrum of the gamma -rays generated by the runaway discharge. The results of the computations are compared with the GRO observations after including the gamma -ray attenuation in the atmosphere }, keywords={ atmospheric radiation fractals gamma-rays lightning stratosphere gamma ray flash model gamma -ray flashes horizontal fractal lightning discharge EM pulses stochastic electron runaway discharge stratosphere gamma -ray flux gamma -ray energy spectrum GRO observations gamma -ray attenuation atmosphere }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LyonsOct98, author={Lyons, W.A. and Nelson, T.E. and Williams, E.R. and Cramer, J.A. and Turner, T.R.}, title={ Enhanced positive cloud-to-ground lightning in thunderstorms ingesting smoke from fires }, journal={Science}, volume={282}, number={5386}, year={1998}, month={Oct}, pages={77-80}, abstract={ Smoke from forest fires in southern Mexico was advected into the U.S. southern plains from April to June 1998. Cloud-to-ground lightning (CG) flash data from the National Lightning Detection Network matched against satellite-mapped aerosol plumes imply that thunderstorms forming in smoke-contaminated air masses generated large amounts of lightning with positive polarity (+CGs). During 2 months, nearly half a million flashes in the southern plains exhibited +CG percentages that were triple the climatological norm. The peak currents in these +CGs were double the expected value. These thunderstorms also produced abnormally high numbers of mesospheric optical sprites }, keywords={ air pollution fires lightning mesosphere smoke thunderstorms enhanced positive cloud-to-ground lightning thunderstorms southern Mexico forest fires USA southern plains AD 1998 04 to 06 lightning flash data National Lightning Detection Network satellite-mapped aerosol plumes smoke-contaminated air masses positive polarity peak currents mesospheric optical sprites }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ValdiviaNov98, author={Valdivia, J.A. and Milikh, G.M. and Papadopoulos, K.}, title={ Model of red sprites due to intracloud fractal lightning discharges }, journal={Radio Science}, volume={33}, number={6}, year={1998}, month={Nov}, pages={1655-68}, abstract={ A new and improved model of red sprites is presented. Emphasis is placed on accounting for the puzzling observation of the spatial structure in the emissions. The model relies on the electromagnetic pulse (EMP) fields created by a horizontal lightning discharge and includes the observed fractal structure of such discharges in the computation of the EMP power density. It is shown that the model can account for the observed spatial structure of the red sprites while reducing the typical charge required to approximately 100 C }, keywords={ atmospheric electricity clouds electromagnetic pulse fractals ionospheric disturbances lightning red sprites intracloud fractal lightning discharges spatial structure electromagnetic pulse fields EMP fields horizontal lightning discharge power density charge 60 to 100 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{RaizerNov98, author={Raizer, Yu.P. and Milikh, G.M. and Shneider, M.N. and Novakovski, S.V.}, title={ Long streamer in the upper atmosphere above thundercloud }, journal={Journal of Physics D (Applied Physics)}, volume={31}, number={22}, year={1998}, month={Nov}, pages={3255-64}, abstract={ It has been suggested that optical flashes observed in the upper atmosphere above giant thunderstorms (red sprites) are due to streamers. Such streamers are initiated in the lower ionosphere by electron patches caused by electromagnetic radiation from horizontal intracloud lightning and then develop downward in the static electric field due to the thundercloud. The triggering conditions of streamer development are analysed. Using similarity relations, known characteristics of streamer tips obtained earlier in laboratory conditions are extended to a description of streamers in rare air. Streamer growth in the nonuniform atmosphere is calculated. It is shown that streamers first appear at a height of about 80 km and then grow downward to slightly below 50 km, where they are terminated. This is in agreement with red sprite observations. An altitude distribution of the streamer generated plasma is obtained. The simple models of streamer development presented in this paper could be applied for computations of streamers growing in other conditions }, keywords={ lightning thunderstorms upper atmosphere long streamers upper atmosphere thunderclouds optical flashes giant thunderstorms red sprites lower ionosphere electron patches EM radiation horizontal intracloud lightning static electric field triggering conditions streamer development streamer tips streamer growth nonuniform atmosphere red sprite observations altitude distribution streamer generated plasma }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{FullekrugNov98, author={Fullekrug, M. and Reising, S.C.}, title={ Excitation of Earth-ionosphere cavity resonances by sprite-associated lightning flashes }, journal={Geophysical Research Letters}, volume={25}, number={22}, year={1998}, month={Nov}, pages={4145-8}, abstract={ Simultaneously recorded discrete excitations of Earth-ionosphere cavity resonances at Silberborn, Germany, and Hollister, California, À9.1 Mm apart, are used to triangulate source locations of lightning flashes in the continental United States with an accuracy of À0.8 Mm, as verified by the National Lightning Detection Network. The identified lightning flashes are mainly associated with positive cloud-to-ground discharges with first return stroke peak currents À20-70 kA. 80% of these particular lightning flashes are associated with sprites, as verified by simultaneous low-light level TV camera observations at Yucca Ridge, Colorado. This high probability of sprite detection is attributed to particularly large cloud-to-ground lightning currents, simultaneously exciting both Earth-ionosphere cavity resonances and sprites }, keywords={ Earth-ionosphere waveguide lightning Earth-ionosphere cavity resonance excitation sprite-associated lightning flashes discrete excitations Silberborn Germany Hollister California source location triangulation lightning flashes continental United States National Lightning Detection Network positive cloud-to-ground discharges first return stroke peak currents low-light level TV camera observations Yucca Ridge Colorado 20 to 70 kA }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{TsunodaMay98, author={Tsunoda, R.T. and Livingston, R.C. and Buonocore, J.J. and Lyons, W.A. and Nelson, T.E. and Kelley, M.C.}, title={ Evidence of a high-altitude discharge process responsible for radar echoes at 24.4 MHz }, journal={Journal of Atmospheric and Solar-Terrestrial Physics}, volume={60}, number={7-9}, year={1998}, month={May}, pages={957-64}, abstract={ Presents preliminary evidence of a high-altitude, electrical discharge process that can produce radar echoes at 24.38 MHz. This conclusion is drawn from pulsed-radar observations of near time-coincident occurrences of impulsive electromagnetic radiation with radar echoes that originated at altitudes well above those of mesoscale convective systems }, keywords={ atmospheric electricity atmospheric electromagnetic wave propagation remote sensing by radar thunderstorms radar echoes HF high-altitude electrical discharge process pulsed-radar observations impulsive EM radiation red sprites blue jets elves upper stratosphere mesosphere 24.38 MHz }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Roussel-DupreMay98, author={Roussel-Dupre, R. and Symbalisty, E. and Taranenko, Y. and Yukhimuk, V.}, title={ Simulations of high-altitude discharges initiated by runaway breakdown }, journal={Journal of Atmospheric and Solar-Terrestrial Physics}, volume={60}, number={7-9}, year={1998}, month={May}, pages={917-40}, abstract={ Detailed 2D hydrodynamic and quasi-electrostatic simulations of high-altitude discharges driven by runaway air breakdown are presented for four cases, corresponding to sprites initiated by positive cloud-to-ground lightning strikes in which 200 C of charge is neutralized at an altitude of 11.5 km in 10, 7, 5 and 3 ms. We find that the computed optical emissions agree well with low-light level camera images of sprites, both in terms of the overall intensity and spatial distribution of the emissions. Our results show the presence of blue emissions extending down to 40 km (blue tendrils) and red sprite tops extending from 50 to 77 km. Simulated spectra show that N$_2$ 1st positive emissions dominate in the wavelength range from 550 to 850 nm, in good agreement with observations. Strong radio pulses with durations of À300 mu s and peak electric field amplitudes ranging from 20 to 75 V/m at an altitude of 80 km and an approximate distance from the discharge of 50 km were computed. The magnitude and duration of these pulses is sufficient to cause breakdown and heating of the lower ionosphere (80-95 km) and leads us to suggest that sprites may also launch the EMP responsible for the production of elves. The computed values for the gamma -ray fluxes are in agreement with observations of gamma -ray bursts of atmospheric origin and the peak secondary electron densities which we obtain are in good agreement with HF echoes at mesospheric heights and associated with lightning }, keywords={ airglow atmospheric electricity atmospheric radiation atmospheric temperature ionospheric disturbances lightning thunderstorms high-altitude discharges runaway breakdown 2D hydrodynamic simulations quasi-electrostatic simulations sprites positive cloud-to-ground lightning strikes optical emissions blue emissions N$_2$ 1st positive emissions radio pulses electric field heating gamma -ray fluxes secondary electron densities mesospheric heights 40 to 80 km 550 to 850 nm 11.5 km N$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MilikhMay98, author={Milikh, G. and Valdivia, J.A. and Papadopoulos, K.}, title={ Spectrum of red sprites }, journal={Journal of Atmospheric and Solar-Terrestrial Physics}, volume={60}, number={7-9}, year={1998}, month={May}, pages={907-15}, abstract={ A synthetic spectrum of red sprites due to electron energization by the electric field from lightning is presented. It is computed by using the electron distribution function obtained from a Fokker-Planck code, which includes various inelastic losses. The model also includes the atmospheric attenuation of the optical emissions. The results are compared with observed red sprite spectra. Some implications of the results to models of red sprites are discussed }, keywords={ airglow atmospheric electricity atmospheric light propagation atmospheric radiation ionospheric disturbances lightning red sprites synthetic spectrum electron energization electric field lightning electron distribution function Fokker-Planck code inelastic losses atmospheric attenuation optical emissions red sprite spectra }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{RycroftMay98, author={Rycroft, M.J. and Cho, M.}, title={ Modelling electric and magnetic fields due to thunderclouds and lightning from cloud-tops to the ionosphere }, journal={Journal of Atmospheric and Solar-Terrestrial Physics}, volume={60}, number={7-9}, year={1998}, month={May}, pages={889-93}, abstract={ Following some lightning flashes from energetic thunderclouds, blue jets and red sprites are observed in the atmosphere above the cloud and into the ionosphere. In order to understand the physical processes leading to these and associated phenomena, both the temporal and spatial evolution of the electric (and magnetic) fields due to the thundercloud and the lightning discharge are modelled. These numerical simulations are carried out either using a quasi-electrostatic code or an EM code, with appropriate boundary conditions and grids. The redistribution of electric charge and the EM pulse due to the lightning, can accelerate electrons, which collide with neutrals and ions, heating them, and also ionising the atmosphere. Runaway electrons and/or electrical breakdown of the atmosphere can also occur. The first and second positive bands of molecular nitrogen are excited appreciably if sufficient energy is produced. The situation is strongly nonlinear. The results show the temporal and spatial development of (a) the electric field divided by the neutral gas density, and (b) the energy density of optical emissions (up to 10/sup 13/ photons m/sup -3/ s/sup -1/). They show that energy propagates up to the ionosphere in 0.3 ms, at the speed of light. A ring of optical emissions is created, the outer rim of which propagates horizontally in the ionosphere at an altitude À90 km, reaching a radial distance of 280 km in a further 0.7 ms. At the same time, the intense electric field at >07 km altitude above the thundercloud creates a much enhanced (À10/sup 3/ x) electron density (with a radius up to 25 km) which lasts for several ms. This heated region modifies the amplitude and phase characteristics of VLF radio waves propagating in the Earth-ionosphere waveguide }, keywords={ airglow atmospheric electricity atmospheric radiation ionospheric disturbances lightning thunderstorms electric fields magnetic fields thunderclouds lightning cloud-top ionosphere blue jets red sprites temporal evolution spatial evolution lightning discharge quasi-electrostatic code EM code electric charge EM pulse heating ionisation electrical breakdown neutral gas density energy density optical emission radial distance electron density heated region VLF radio waves propagation Earth-ionosphere waveguide 0 to 90 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Mengu-ChoMay98, author={Mengu Cho and Rycroft, M.J.}, title={ Computer simulation of the electric field structure and optical emission from cloud-top to the ionosphere }, journal={Journal of Atmospheric and Solar-Terrestrial Physics}, volume={60}, number={7-9}, year={1998}, month={May}, pages={871-88}, abstract={ Computer simulations are carried out to study the sprite' onset mechanism. Both electrostatic and electromagnetic codes are developed to calculate the electric field structure and optical emission intensity between the top of the thundercloud and the ionosphere. The optical emission is composed of two structures. One peaks at 70 km height and its lateral dimension is 50-60 km; the other peaks at 90 km height and the lateral dimension extends beyond 200 km. It is found that the nitrogen first positive band, which has a red colour, dominates over the nitrogen second positive band except at the bottom of the optical emission. The upper part of the optical emission is caused by a horizontally travelling electromagnetic pulse induced by a lightning discharge current. The lower structure is caused by electrostatic effects induced by the unneutralized charge left after the lightning discharge current flows. The electromagnetic codes developed can simulate the self-consistent response of the upper atmosphere to the lightning discharge current. The electrostatic treatment can predict only the optical emission at heights less than À80 km. The optical emission intensity has a strong nonlinear dependence on the electric field strength through the enhanced electron density, and is increased for a long discharge path, a large current, and a short pulse. Also, the higher the lightning discharge is initiated, the brighter the optical emission is, because the electrostatic field is stronger for high altitude lightning }, keywords={ airglow atmospheric electricity atmospheric radiation ionospheric disturbances lightning electric field structure optical emission cloud-top ionosphere sprite electrostatic codes electromagnetic codes optical emission intensity thundercloud lateral dimension first positive band horizontally travelling electromagnetic pulse electrostatic effects unneutralized charge lightning discharge current self-consistent response electrostatic treatment nonlinear dependence electric field strength enhanced electron density discharge path current short pulse 0 to 120 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{RowlandMay98, author={Rowland, H.L.}, title={ Theories and simulations of elves, sprites and blue jets }, journal={Journal of Atmospheric and Solar-Terrestrial Physics}, volume={60}, number={7-9}, year={1998}, month={May}, pages={831-44}, abstract={ This review considers the different models that have been developed to explain a class of phenomena that occur above lightning storms. These phenomena have been named elves, red sprites and blue jets. The elves appear between 90 and 70 km altitude and extend over several 100 km horizontally. They are visible for less than 0.1 ms. Red sprites cover a range of altitudes from 80 to 55 km with narrow tendrils extending below 55 km. Horizontally they are 20-30 km wide. Their visible lifetime is from a few to some tens of ms. Blue jets propagate from cloud tops (15 km) to an altitude of 40 km with a velocity of 100 km/s which gives a lifetime of 300 ms. In all of the models, the energy source is the electric fields associated with the lightning-the quasistatic fields due to the original charge distribution, the electromagnetic pulse due to the propagation of the return stroke or the quasistatic fields due to the charge redistribution by the currents. There are two different models to explain the heating of the neutral atmosphere by these electric fields. These models accelerate either the ambient thermal electrons (or=75 kA. Large peak current positive CGs (LPC+CGs) are concentrated in the High Plains and upper Midwest, the region in which a large majority of optical sprite and elves observations have been obtained. By contrast, large peak current negative CGs (LPC-CGs) preferentially occur over the coastal waters of the Gulf of Mexico and the southeastern United States. A total of 1.46 million LPCCGs were found, of which only 13.7% were +CGs. Almost 70% of the LPC+CGs, however, occurred in the central United Stares (30 degrees -50 degrees N, 88 degrees -110 degrees W). The percentage of all LPCCGs that were positive approached 30% in the central United States compared to 4.5% for the remainder of the country. Over a half million negative CGs and over 1000 positive CGs were found with multiplicity }, keywords={ lightning mesosphere stratosphere large peak current cloud-to-ground lightning flashes boreal summer months contiguous United States positive polarity sprites elves stratosphere mesosphere US National Lightning Detection Network AD 1991 to 1995 geographic distribution peak currents High Plains Midwest Gulf of Mexico multiplicity USA }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ErnstmeyerJul98, author={Ernstmeyer, J. and Chang, T.}, title={ Lightning-induced electron heating in the mesosphere }, journal={Geophysical Research Letters}, volume={25}, number={13}, year={1998}, month={Jul}, pages={2389-92}, abstract={ A multiple-fluid, quasi-electrostatic simulation model is used to examine the effects of lightning on the atmosphere between 20 km and 90 km altitude. Two principal new results are obtained; (1) first, significant space charge is found in the altitude range 20 to 40 km during a positive, but not negative, cloud-to-ground (CG) discharge. (2) Second, a lightning flash is shown to increase total conductivity in the altitude range of 20 to 40 km by at least an order of magnitude, 10 s after the discharge. This is due to the lingering effects of the ion and electron redistribution caused by the lightning discharge }, keywords={ atmospheric electricity atmospheric temperature lightning mesosphere stratosphere lightning-induced electron heating mesosphere multiple-fluid quasi-electrostatic simulation model space charge positive cloud-to-ground discharge lightning flash total conductivity ion redistribution electron redistribution 20 to 90 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HardmanApr98, author={Hardman, S.F. and Rodger, C.J. and Dowden, R.L. and Brundell, J.B.}, title={ Measurements of the VLF scattering pattern of the structured plasma of red sprites }, journal={IEEE Antennas and Propagation Magazine}, volume={40}, number={2}, year={1998}, month={Apr}, pages={29-38}, abstract={ Analysis of a large number of VLF scattering events associated with sprites results in an average scattering distribution having a strong frontal lobe, and also having strong large-angle scattering. This is consistent with the scattering pattern produced by a theoretical model of the sprite as an array of interacting vertical plasma columns, indicating that some part of the sprite is "hard" and contains complex structure (most likely the "stalactites" seen in optical sprites). Attempting to determine the scattering distribution due to sprites using a high threshold for event detection could result in observation of only the frontal lobe and the minima on either side of it, and not the scattering at larger angles. This problem would be worsened by the use of only amplitude, and not phase, monitoring to detect perturbations, and could lead experimenters to the conclusion that sprites are narrow-angle scatterers, with a smoothly varying diffuse structure }, keywords={ electromagnetic wave scattering ionospheric electromagnetic wave propagation lightning mesosphere radiowave propagation thermosphere VLF scattering pattern structured plasma red sprites scattering distribution frontal lobe large-angle scattering interacting vertical plasma columns amplitude monitoring phase monitoring perturbations }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PaskoJun98, author={Pasko, V.P. and Inan, U.S. and Bell, T.F.}, title={ Spatial structure of sprites }, journal={Geophysical Research Letters}, volume={25}, number={12}, year={1998}, month={Jun}, pages={2123-6}, abstract={ A theory of the electrical breakdown (EB) above thunderstorms is developed. The streamer type of the EB is proposed for the explanation of observations of fine spatial structures and bursts of blue optical emissions associated with sprites }, keywords={ atmospheric electricity lightning mesosphere thunderstorms spatial structure sprites electrical breakdown thunderstorms streamer type bursts blue optical emissions }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Chakravarty97, author={Chakravarty, S.C. and Gupta, S.P. and Chandrasekaran, S.}, title={ Middle atmospheric electrodynamics at low latitude over India }, journal={Advances in Space Research}, volume={20}, number={11}, year={1997}, month={}, pages={2181-9}, abstract={ Low latitude middle atmospheric electrodynamics has a number of interesting features such as low flux of cosmic rays due to high cut-off rigidities, higher solar electromagnetic radiation intensities and mesospheric ionisation, large scale convection and wide-spread lightning phenomena, higher tropopause level and special characteristics associated with the equatorial electrojet. These special features play a vital role in governing the electrodynamics of the global middle atmosphere. In India, a well coordinated multi-institutional campaign was organised under MAP (middle atmosphere programme) to carry out balloon and rocket borne experiments to measure electrical parameters of the middle atmosphere. The measured parameters include electron/ion densities and mobilities, polar ion conductivities and electric fields. The experiments were carried out during different seasons and solar activity epochs. The results obtained from these investigations are discussed and compared with similar measurements over the middle latitude stations to assess the integrated effect of the global atmospheric electrodynamic phenomenon }, keywords={ atmospheric electricity atmospheric temperature cosmic ray interactions D-region electric fields electrodynamics electron density mesosphere stratosphere wind atmospheric electrodynamics low latitude middle atmosphere electron densities ion densities ion mobilities ion conductivities electric fields different seasons different solar activity epochs stratosphere middle latitude balloon campaigns temporal variations vertical profiles ion chemical scheme cosmic ray ion production rates mesosphere rocket sounding zonal wind meridional wind D region atmospheric temperature wave like features India }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BellApr98, author={Bell, T.F. and Reising, S.C. and Inan, U.S.}, title={ Intense continuing currents following positive cloud-to-ground lightning associated with red sprites }, journal={Geophysical Research Letters}, volume={25}, number={8}, year={1998}, month={Apr}, pages={1285-8}, abstract={ In July-August, 1996, Stanford University carried out broadband ELF/VLF measurements of the magnetic field radiated by positive cloud-to-ground (CG) discharges associated with Red Sprites. The authors report these measurements for 17 sprite associated discharges that occurred during a 15 minute period on August 1, 1996. The current and charge moments for each of the events are deduced, and it is found that, in every case, intense continuing currents of À1 ms duration are responsible for most of the positive charge transfer to ground that precedes the appearance of the sprite. The time delay between the causative positive discharge and the video field in which the sprite first appeared varied from 0 to 15 ms for the larger events to as much as 100 ms for the smaller events. The authors suggest that in the smaller events the removal of significant positive charge during this delay interval is accomplished through a horizontal intracloud discharge }, keywords={ atmospheric electricity lightning thunderstorms atmosphere stratosphere sprite intense continuing current electric current positive cloud-to-ground lightning red sprite AD 1996 07 AD 1996 08 ELF VLF radiowave emission positive cloud-to-ground discharge positive charge transfer causative positive discharge time delay horizontal intracloud discharge thunderstorm }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{CummerApr98, author={Cummer, S.A. and Inan, U.S. and Bell, T.F. and Barrington-Leigh, C.P.}, title={ ELF radiation produced by electrical currents in sprites }, journal={Geophysical Research Letters}, volume={25}, number={8}, year={1998}, month={Apr}, pages={1281-4}, abstract={ Measurements of ELF-radiating currents associated with sprite-producing lightning discharges exhibit a second current peak simultaneous in time with sprite luminosity, suggesting that the observed ELF radiation is produced by intense electrical currents flowing in the body of the sprite }, keywords={ atmospheric electricity atmospheric radiation lightning mesosphere stratosphere thermosphere stratosphere mesosphere thermosphere middle atmosphere upper atmopshere radiowave emission ELF radiation electric current electrical current sprite lightning discharge second current peak }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{WaubenFeb98, author={Wauben, W.M.F. and Fortuin, J.P.F. and van Velthoven, P.F.J. and Kelder, H.M.}, title={ Comparison of modeled ozone distributions with sonde and satellite observations }, journal={Journal of Geophysical Research}, volume={103}, number={D3}, year={1998}, month={Feb}, pages={3511-30}, abstract={ The global distribution of ozone in the troposphere and lower stratosphere calculated with a three-dimensional chemistry transport model driven by European Centre for Medium-Range Weather Forecasts (ECMWF)-analyzed meteorological fields has been compared with observed ozonesonde profiles. This comparison is presented in a new graphical format, which shows in a single panel the vertical and seasonal dependence. The modeled ozone profiles compare reasonably well with climatological ozonesonde data for various stations all over the world, especially if the variability of the ozone concentrations is taken into account. However, the ozone mixing ratios in the upper troposphere and lower stratosphere at midlatitudes are generally overestimated by the model. This is probably caused by a combination of an overestimation of the stratosphere-troposphere exchange and the absence of heterogeneous reactions in the lower stratosphere which reduce ozone. The latitudinal dependence and seasonal dependence of the observations are reproduced by the model calculations, except for the ozone concentrations at the surface. This might be due to the neglect of nonmethane hydrocarbons, which give rise to photochemical ozone production during summer, although other factors such as emissions and deposition cannot be ruled out. The ozone column density obtained by combining calculated ozone distributions up to 50 hPa with climatological zonal mean data for ozone above 50 hPa compares reasonably well with total ozone mapping spectrometer (TOMS) observations. In this study a methane and carbon monoxide oxidation chemistry scheme has been employed without stratospheric chemistry. Furthermore, the comparison of TOMS total ozone observations in the tropics with model calculations seems to suggest that the treatment of ozone precursors such as the NO, emissions by lightning and biomass burning needs to be improved }, keywords={ air pollution atmospheric composition ozone stratosphere troposphere atmosphere stratosphere troposphere chemistry chemical composition air pollution ozone global distribution model satellite observations three-dimensional model chemistry transport model ECMWF seasonal dependence season vertical profile latitude nonmethane hydrocarbon O/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @TECHREPORT{KrausFeb97, author={Kraus, A.B.}, title={ Global distribution of tropospheric NO/sub x/: a three-dimensional model study }, journal={}, institution={}, year={1997}, pages={ 155}, abstract={ The nitrogen oxides NO and NO$_2$, which are lumped into NO/sub X/, play a dual role in tropospheric chemistry. On the one hand they are the most important species with respect to the net tropospheric ozone production, on the other hand they control the concentration of the hydroxyl radical. Thus, the distribution of NO/sub X/ must be known before distributions of these two species can be calculated. However, because of the short chemical lifetime and the resulting high temporal and spatial variability of NO/sub X/, this distribution is difficult to determine by measurements, at least on a global scale. In the present study an existing three-dimensional chemical tracer model was extended in order to characterize the global distribution of tropospheric NO/sub X/. This was done by implementing a known, linear NO/sub X/ chemistry scheme and emission scenarios for the following six sources of tropospheric NO/sub X/: fossil fuel combustion, soil microbial activity, lightning discharges, biomass burning, downward transport from the stratosphere, and aircraft emissions. Since the uncertainty of each of these sources is a factor of 2 at least, the resulting global NO/sub X/ distributions are associated with corresponding uncertainties as well. A new parametrization was developed for the lightning source in which the relative distribution of global lightning activity is derived from the convection statistics included in the present model. Two parameters are used to weight individual convection convection events according to observed monthly mean relative lightning distributions. The relative distributions are scaled by an absolute emission rate derived from global estimates }, keywords={ atmospheric chemistry atmospheric composition convection lightning nitrogen compounds thunderstorms troposphere hydroxyl radical aircraft measurements atmospheric chemistry troposphere chemical tracer model global distribution fossil fuel combustion soil microbial activity lightning discharges biomass burning downward transport aircraft emissions sources NO/sub X/ distributions convection statistics emission rate model chemistry monthly mean zonal mean vertical profiles NO NO$_2$ HNO/sub 3/ }, } /usr/tmp/citation.tmp.27694 @ARTICLE{MendeAug97, author={Mende, S.B. and Sentman, D.D. and Wescott, E.M.}, title={ Lightning between Earth and space }, journal={Scientific American (International Edition)}, volume={277}, number={2}, year={1997}, month={Aug}, pages={56-9}, abstract={ Once dismissed as figments of pilots' imaginations, strange flashes appearing above thunderstorms have been confirmed as entirely new forms of lightning. Known as sprites, elves, blue jets and gamma-ray events, these high-altitude phenomena arise through a physics all their own. Their features and origin are discussed }, keywords={ lightning mesosphere thermosphere thunderstorms flashes thunderstorms lightning sprites elves blue jets gamma-ray events high-altitude phenomena origin 50 to 90 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{OrvilleApr97, author={Orville, R.E. and Silver, A.C.}, title={ Lightning ground flash density in the contiguous United States: 1992-95 }, journal={Monthly Weather Review}, volume={125}, number={4}, year={1997}, month={Apr}, pages={631-8}, abstract={ Cloud-to-ground lightning data for the years 1992-95 have been analyzed for geographical distribution of total flashes, positive flashes, and the percentage of flashes that lower positive charge to ground. In the contiguous United States the measured total cloud-to-ground lightning flash counts were 16.3 million (1992), 24.2 million (in both 1993 and 1994), and 22.3 million in 1995. The maximum flash densities occurred in Florida in 1992 (9-11 flashes per square kilometer) and in the Midwest in 1993 (11-13 flashes per square kilometer), coinciding with the storms and floods that dominated the summer of 1993 in the Midwest. In 1994, the area of maximum flash density was again in Florida (11-13 flashes per square kilometer). In 1995, the flash density maxima (911 km/sup -2/) were in southern Louisiana and near the Kentucky-Illinois border. Positive flash densities had maxima in the Midwest in all four years with values of 0.4 (1992), 1.0 (1993), 0.7 (1994), and 1.8 flashes per square kilometer (1995). The annual mean percentage of flashes that lowered positive charge to ground was between 4% and 5% for the three years, 1992-94, but increased to 9.3% in 1995. The monthly values of the percentage of positive flashes ranged from 3% (August 1992) to 258 (December 1993). The positive flash maxima in the Midwest appear to be near the geographical areas in which cloud-ionosphere discharges (sprites) have been reported }, keywords={ lightning USA United States storm thunderstorm AD 1992 AD 1993 AD 1994 AD 1995 lightning ground flash density cloud-to-ground lightning geographical distribution spatial distribution total flashes positive flash positive charge to ground Midwest Florida Louisiana Kentucky Illinois cloud-ionosphere discharge sprite }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ValdiviaDec97, author={Valdivia, J.A. and Milikh, G. and Papadopoulos, K.}, title={ Red sprites: lightning as a fractal antenna }, journal={Geophysical Research Letters}, volume={24}, number={24}, year={1997}, month={Dec}, pages={3169-72}, abstract={ A new and improved model of red sprites is presented. Emphasis is placed in accounting for the puzzling observation of the spatial structure in the red sprite's optical emissions. The model relies upon a horizontal fractal lightning discharge, which generates the EMPs that excites the optical emissions in the lower ionosphere. It is shown that the fractal model may account for the observed sprite's spatially structured optical pattern, while reducing the typical charge threshold to approximately 100 C }, keywords={ atmospheric electricity fractals lightning mesosphere nightglow thermosphere upper atmosphere middle atmosphere mesosphere upper atmosphere thermosphere lightning nightglow stratosphere red sprite fractal antenna model spatial structure optical emission horizontal fractal lightning discharge electric discharge EMP electromagnetic pulse }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Yukhimuk97, author={Yukhimuk, V. and Roussel-Dupre, R. and Symbalisty, E. and Taranenko, Y.}, title={ Optical, radio and X-ray radiation of red sprites produced by runaway air breakdown }, booktitle={XXIII International Conference on Phenomena in Ionized Gases, ICPIGProceedings. Contributed Papers}, volume={}, number={}, year={1997}, month={}, pages={52-3 vol.3}, abstract={ We use the runaway air breakdown model of upward discharges to calculate optical, radio, and X-ray radiation generated by red sprites. Red sprites are high altitude (up to 90 km) lightning discharges. Aircraft based observations (Sentman et al., 1995) show that sprites are predominantly red in color at altitudes above À55 km with faint blue tendrils, which extend downward to an altitude of 40 km; the duration of a single sprite is less than 17 ms, their maximum brightness is about 600 kR, and estimated total optical energy is about 1-5 kJ per event. The ground based observations show similar results, and provide some additional information on spatial and temporal structure of sprites (Winckler et al., 1996), and on sprite locations (Lyons et al., 1996). One difference between aircraft and ground-based observations is that blue tendrils are rarely observed from the ground. Sprites usually occur above the anvils of large mesoscale convective systems and correlate with strong positive cloud to ground discharge (Boccipicio et al., 1995). Upward discharges are the most probable source of X-ray emission observed above large thunderstorm complexes by the Compton Gamma-ray Observatory (Fishman et al., 1994). To escape the atmosphere these gamma -rays must originate above 25 km altitude. Red sprites are usually observed at altitudes higher than 50 km, and are therefore a likely source of this X-ray emission }, keywords={ atmospheric radiation brightness lightning mesosphere thermosphere optical radiation generation radiofrequency radiation generation X-ray radiation generation red sprites runaway air breakdown model upward discharges high altitude lightning discharges aircraft based observations faint blue tendrils sprite altitude sprite duration maximum brightness total optical energy ground based observations spatial structure temporal structure anvils large mesoscale convective systems strong positive cloud to ground discharge large thunderstorm complexes Compton Gamma-ray Observatory 90 km 55 km 40 km 17 ms 1 to 5 kJ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Symbalisty97, author={Symbalisty, E. and Roussel-Dupre, R. and Yukhimuk, V. and Taranenko, Y.}, title={ High altitude atmospheric discharges according to the runaway air breakdown mechanism }, booktitle={XXIII International Conference on Phenomena in Ionized Gases, ICPIGProceedings. Contributed Papers}, volume={}, number={}, year={1997}, month={}, pages={12-13 vol.3}, abstract={ High altitude optical transients-red sprites, blue jets, and elves-are modeled in the context of the relativistic electron runaway air breakdown mechanism. These emissions are usually with large mesoscale convective systems (hereafter MCS). In thunderstorms cloud electrification proceeds over time scale long enough to permit the conducting atmosphere above the cloud to polarize and short out the thunderstorm electric field. When a lightning strike rapidly neutralizes a cloud charge layer runaway driving fields can develop in the stratosphere and mesosphere. According to the authors' simulations of the full runaway process the variety of observed optical emissions are due to the nature of the normal lightning event in the MCS that kick starts the runaway avalanche. The authors describe some details of the model, present the results of the evolution of the primary electron population, and summarize the initial conditions necessary for different types of discharges. Two companion papers present: (a) the predicted optical, gamma ray, and radio emissions caused by these electrical discharges, and (b) the time evolution of the secondary electron population and its implications in terms of observables }, keywords={ atmospheric electricity atmospheric ionisation lightning mesosphere stratosphere mesosphere middle atmosphere lightning electric discharge high altitude atmospheric discharge runaway air breakdown mechanism optical transient red sprite red sprites blue jets blue jet elf elves relativistic electron runaway air breakdown mechanism thunderstorm cloud electrification electric field stratosphere }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Roussel-Dupre97, author={Roussel-Dupre, R. and Fitzgerald, T.J. and Symbalisty, E. and Blanc, E.}, title={ HF echoes from ionization potentially produced by high-altitude discharges }, booktitle={XXIII International Conference on Phenomena in Ionized Gases, ICPIGProceedings. Contributed Papers}, volume={}, number={}, year={1997}, month={}, pages={10-11 vol.3}, abstract={ The authors report on recent radar measurements taken during the month of October 1994 with the LDG HF radar in the Ivory Coast, Africa as part of the International Equatorial Electrojet Year. The purpose of this experimental effort in part was to study the effects of thunderstorms on the ionosphere. At the same time, they decided to carry out a set of experiments of an exploratory nature to look for echoes that could potentially arise from ionization produced in the mesosphere. The two leading candidates for producing transient ionization in the mesosphere are meteors and high-altitude discharges. Each is discussed in the context of their measurements }, keywords={ airglow atmospheric ionisation ionosphere lightning mesosphere radar observations HF echo ionization high-altitude discharge electric discharge sprite jet elves elf sprites lightning middle atmosphere AD 1994 10 mesosphere ionosphere meteor Ivory Coast West Africa thunderstorm transient ionization }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Taranenko97, author={Taranenko, Y. and Roussel-Dupre, R. and Yukhimuk, V. and Symbalisty, E.}, title={ Generation of elves by sprites and jets }, booktitle={XXIII International Conference on Phenomena in Ionized Gases, ICPIGProceedings. Contributed Papers}, volume={}, number={}, year={1997}, month={}, pages={8-9 vol.3}, abstract={ Recent years of observations of the upper atmosphere and the lower ionosphere brought a fascinating collection of new phenomena including optical, radio, and gamma-ray emissions originating in the 20 to 90 km altitude range. Up to now, the most diverse phenomenology has emerged from the optical observations which have led to the identification of red sprites, blue jets, blue starters and elves. Most of the previous studies have concentrated on relating such phenomena in the upper atmosphere to regular lightning discharges in the troposphere. For example, sprites and jets are believed to be optical manifestations of electrical discharges in the upper atmosphere caused by quasi-electrostatic fields penetrating to high altitudes during a regular lightning discharge. The sprite/jet discharge itself can be caused by the runaway air breakdown or regular air breakdown. The standard theory for optical airglow transients in the lower ionosphere above the thunderstorms also known as elves suggests that they are produced during interaction of electromagnetic pulses (EMP) from lightning with the lower ionosphere. Heating of the ambient electrons by the EMP in the D-region can result in excitation of optical emissions once the optical excitation thresholds are reached. In this paper the authors suggest that in addition to this mechanism elves can be caused by an EMP generated by sprites and jets. If sprites and jets are indeed accompanied by electrical discharges then some energy of their EMPs reaches to the ionosphere and heats ambient electrons there that in turn stimulates optical emissions similar to EMPs from regular lightning }, keywords={ airglow ionosphere lightning mesosphere stratosphere mesosphere middle atmosphere lightning stratosphere ionosphere generation formation model elves sprite jet elf red sprite blue jet blue starters electrical discharge EM pulse runaway air breakdown theory airglow electromagnetic pulse EMP D-region }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HockingNov97, author={Hocking, W.K.}, title={ Recent advances in radar instrumentation and techniques for studies of the mesosphere, stratosphere, and troposphere }, journal={Radio Science}, volume={32}, number={6}, year={1997}, month={Nov}, pages={2241-70}, abstract={ There have been significant advances in mesosphere-stratosphere-troposphere (MST) radar studies. This is true with respect to studies ranging from MF through VHF and up to UHF. These advances have been in each of the areas of equipment, techniques, and general radar theory. In this paper we highlight some of these advances and discuss their significance in the longer-term application of MST radar techniques. We concentrate primarily on discussion about instrumentation and the raw products (powers, radial velocities, and spectral widths) produced by the systems, with some reference to the nature of the radio wave scattering entities. Quantities which are derived from the measurements of these raw quantities like gravity wave fluxes, tidal studies, and so forth will not generally be considered in any detail. Sample advances include new methods of data analysis (both on-line and post-collection), lightning detection, rainfall measurement, and temperature determination. Other interesting applications include simultaneous application of MST techniques with other procedures such as in radio acoustic sounding (RASS) and the artificial periodic inhomogeneity (API) method. Areas of advance in terms of understanding scattering mechanisms include new insights into the controversy about the nature of aspect-sensitive scattering (specular reflection compared with anisotropic turbulence) and improvements and refinements in our measurements of turbulence with these radars. The paper will concentrate on radars which can employ clear-air scattering }, keywords={ atmospheric measuring apparatus atmospheric techniques electromagnetic wave scattering mesosphere remote sensing by radar reviews stratosphere troposphere radar instrumentation mesosphere stratosphere troposphere MST radar studies VHF UHF radar theory MF powers radial velocities spectral widths radio wave scattering gravity wave fluxes data analysis lightning detection rainfall measurement temperature determination radio acoustic sounding RASS artificial periodic inhomogeneity method API method scattering turbulence 2 to 2700 MHz }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{FukunishiDec97, author={Fukunishi, H. and Takahashi, Y. and Sato, M. and Shone, A. and Fujito, M. and Watanabe, Y.}, title={ Ground-based observations of ULF transients excited by strong lightning discharges producing elves and sprites }, journal={Geophysical Research Letters}, volume={24}, number={23}, year={1997}, month={Dec}, pages={2973-6}, abstract={ Optical and search coil magnetometer data obtained from the SPRITES'96 campaign carried out at Yucca Ridge Field Station, Colorado in July 1996 have presented clear evidence for the excitation of ULF transients with their dominant power at 1-2 Hz by strong lightning discharges producing elves and sprites. The most striking feature is that the ULF transients exhibit different wave forms in the case of sprites without preceding elves and the case of sprites with preceding elves. In the former case damped, quasi-sinusoidal oscillations commence impulsively at the onset of sprites, while in the latter case quasi-sinusoidal wavelets with a duration of À3 s are excited, and elves and sprites occur within each wavelet. It is likely that these ULF transients are due to the nonlinear excitation of the ionospheric Alfven resonator by strong lightning discharge, as proposed by Sukhorukov and Stubbe [1997] }, keywords={ Earth-ionosphere waveguide lightning Earth ionosphere waveguide Earth ionosphere cavity radiowave propagation ground-based observations ULF transients ULF transient strong lightning discharge elves sprites sprite elf EM wave propagation excitation AD 1996 07 damped quasi-sinusoidal oscillation quasi-sinusoidal wavelet nonlinear excitation ionospheric Alfven resonator 1 to 2 Hz }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Tsukuda97, author={Tsukuda, T.}, title={ Sizes and some features of luminous sources associated with the 1995 Hyogo-ken Nanbu earthquake }, journal={Journal of Physics of the Earth}, volume={45}, number={2}, year={1997}, month={}, pages={73-82}, abstract={ Sources of luminescence and their build-up processes accompanying the 1995 Hyogo-ken Nanbu earthquake of M 7.2 are studied based on pieces of information obtained mainly by interviewing eyewitnesses. Gross forms of relatively large-scale luminous sources are roughly classified into four types: lightning with zigzag lines, a swelling shield-shaped source, an upward-extending fan-shaped source, and a belt of lights. The last one includes an arc-like source. Each source is predominantly in tones of either colorless-white, blue or orange-color. This paper presents 23 spottings, distributed as widely as 50 km from the epicenter of the mainshock near Kobe City. Along with these spottings, some local flashing events were reported. The upper limit of the height of several sources was able to be estimated as less than 200 m above the ground. The linear dimension of the horizontal extent ranged from about 1 to 8 km. The luminance was estimated to be more than an order of 10/sup 3/ cd/m/sup 2/ for an arc-like orange colored source at the eastern part of the aftershock area. According to most of the eyewitnesses, the luminosity started from ground level on land, suggesting that discharge processes of the polarized electricity in near-surface rocks may be the primary driving force of the luminescence. However, electricity charged in the air should be also responsible for some luminous phenomena, especially a kind of lightning above the sea. Fog or dust was observed in the air in the region around Nishinomiya City, east of Kobe, preceding the quake, which might have played the role of an effective electrical conductor in glow discharge }, keywords={ earthquakes glow discharges lightning luminescence Hyogo-ken Nanbu earthquake luminous sources AD 1995 01 17 luminescence eyewitness reports lightning shield-shaped source fan-shaped source arc-like source colour glow discharge electrical conductor Kobe City Honshu Japan flashing events horizontal extent source height luminance aftershock area discharge processes polarized electricity near-surface rocks electrically charged air fog dust Nishinomiya City }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{DowdenNov97, author={Dowden, R.L. and Rodger, C.J.}, title={ Decay of a vertical plasma column: a model to explain VLF sprites }, journal={Geophysical Research Letters}, volume={24}, number={22}, year={1997}, month={Nov}, pages={2765-8}, abstract={ VLF sprites are identified by high angle scattering of VLF transmissions by the conducting plasma columns which appear as the luminous columns of "red sprites". VLF sprites are "early/fast Trimpis" and probably vice versa. Recently discovered properties of early/fast Trimpis are the logarithmic decay of the amplitude of the scattered signal and monotonic variation of its phase. These properties are explained in terms of scattering from a vertical column or set of columns extending from 50 km (or lower) altitude to about 80 km }, keywords={ atmospheric electromagnetic wave propagation Earth-ionosphere waveguide lightning mesosphere radiowave propagation stratosphere middle atmosphere ionosphere radiowave propagation VLF Trimpi vertical plasma column decay stratosphere mesosphere model VLF sprite high angle scattering radiowave transmission conducting plasma column luminous column red sprite early/fast Trimpis logarithmic decay phase variation scattering Earth ionosphere waveguide 30 to 80 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LehtinenNov97, author={Lehtinen, N.G. and Bell, T.F. and Pasko, V.P. and Inan, U.S.}, title={ A two-dimensional model of runaway electron beams driven by quasi-electrostatic thundercloud fields }, journal={Geophysical Research Letters}, volume={24}, number={21}, year={1997}, month={Nov}, pages={2639-42}, abstract={ Intense, transient quasi-electrostatic (QE) fields, which exist above thunderclouds following a positive cloud-to-ground lightning discharge, can produce an upward travelling runaway electron (REL) beam. A new two-dimensional (2D) REL-QE model is developed, expanding the previously reported 1D model [Bell et al., 1995] and incorporating the QE [Pasko et al., 1997] and the electrostatic heating (ESH) [Pasko et al., 1997] models. The new model gives the lateral electron distribution in the beam and allows us to determine the ionospheric effects and the optical luminosities resulting from the simultaneous action of the QE fields on the ambient electrons and the runaway electrons. The model is self-consistent and includes the changes in space charge and conductivity due to the REL. Optical emissions and gamma -ray emissions [Lehtinen et al., 1996] are calculated and compared to experimental observations of sprites and terrestrial gamma -ray flashes (TGF). It is shown that the structure of the electric field and the optical emissions can be significantly affected by the REL }, keywords={ atmospheric electricity atmospheric radiation electron beams ionospheric disturbances mesosphere thunderstorms two-dimensional model runaway electron beams quasi-electrostatic thundercloud fields transient quasi-electrostatic fields thunderclouds positive cloud-to-ground lightning discharge upward travelling runaway electron beam REL-QE model electrostatic heating lateral electron distribution ionospheric effects optical luminosities space charge optical emissions gamma -ray emissions terrestrial gamma -ray flashes sprites }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{FlatoySep97, author={Flatoy, F. and Hov, O.}, title={ NO/sub x/ from lightning and the calculated chemical composition of the free troposphere }, journal={Journal of Geophysical Research}, volume={102}, number={D17}, year={1997}, month={Sep}, pages={21373-81}, abstract={ In the free troposphere, injection from the stratosphere, emissions at the surface transported upward by dynamic processes, aircraft emissions and production in lightning strokes are the main sources of oxides of nitrogen (NO/sub x/). The global source of NO/sub x/ production by lightning is not well known and estimates vary from 3 to 650 Mt NO$_2$/yr. In this paper the role of regional and episodic emissions of NO/sub x/ from lightning is examined with a three-dimensional chemistry transport model, and a parameterization of the emissions is proposed, linking it to the intensity of latent heat generation in convection calculated in a numerical weather prediction model. The parameterization is scaled to give an annual global emission of 16 MtNO$_2$/yr. The resulting distribution of the concentration of NO/sub x/, ozone, OH and nonmethane hydrocarbons is compared for the free troposphere over the northern hemisphere with the results of a calculation where the total NO/sub x/ emissions from lightning were about the same but were fixed in time and space over the 18 day calculation (June 18 to July 5, 1995). The maximum differences in the free tropospheric concentrations are significant: for NO/sub x/, OH and nonmethane hydrocarbon of the same order of magnitude as the concentrations themselves, for ozone 1 order of magnitude less than the ozone concentration. This means that NO/sub x/ emissions from lightning may cause a variability in free tropospheric composition which makes it quite difficult to distinguish the importance of other sources of free tropospheric NO/sub x/ from that of lightning in periods when lightning occurs }, keywords={ atmospheric chemistry atmospheric composition atmospheric movements atmospheric temperature lightning nitrogen compounds troposphere NO/sub x/ lightning chemical composition free troposphere global source regional emissions episodic emissions three-dimensional chemistry transport model latent heat generation convection concentration nonmethane hydrocarbons northern hemisphere AD 1995 06 18 to 07 05 OH NO$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Babich97, author={Babich, L.P. and Kutsyk, I.M. and Kudryavtsev, A.Yu. and Mozgovoi, A.L.}, title={ The effect of the geomagnetic field on the development of the upward atmospheric discharge }, booktitle={XXIII International Conference on Phenomena in Ionized Gases, ICPIGProceedings. Contributed Papers}, volume={}, number={}, year={1997}, month={}, pages={6-7 vol.1}, abstract={ Roussel-Dupre and Gurevich have developed a theory of gigantic atmospheric discharges directed upward from thundercloud tops into the Earth's stratosphere (1996). Formation of relativistic runaway electron avalanche initiated by cosmic-ray showers within the space domain of a thunderstorm electric field, is the heart of the theory. The theory allowed one to treat the origin of wide columns of light radiance observed repeatedly above thunderclouds. These light phenomena are known as "blue jets" emitted blue light at altitudes below 35 km, and "red sprites" emitted red light at altitudes above 60 km. Roussel-Dupre and Gurevich have pointed out that geomagnetic field affected essentially the dynamics of gas discharge processes responsible for the light emission phenomena observed, especially at high altitudes above 40 km, where electron-neutral collision frequency is reduced to become lower than local value of the electron cyclotron frequency due to lower air density. However the theory of the upward atmospheric discharges developed by now by Roussel-Dupre, Gurevich, Tunnel and Milikh, did not incorporated adequately the effect of geomagnetic field (1994). So this problem remains to be solved. Results of the first calculations carried out with the aim to evaluate the effect of the geomagnetic field on the development of the relativistic runaway electron avalanche, are delivered in the present communication }, keywords={ atmospheric electricity discharges (electric) lightning mesosphere stratosphere thunderstorms middle atmosphere mesosphere stratosphere optical emission airglow lightning red sprite magnetic field effect geomagnetic field development upward atmospheric discharge electric discharge theory gigantic atmospheric discharges thundercloud top thunderstorm relativistic runaway electron avalanche electric field blue jet dynamics gas discharge light emission }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{JenkinsAug97, author={Jenkins, G.S. and Mohr, K. and Morris, V.R. and Arino, O.}, title={ The role of convective processes over the Zaire-Congo Basin to the southern hemispheric ozone maximum }, journal={Journal of Geophysical Research}, volume={102}, number={D15}, year={1997}, month={Aug}, pages={18963-80}, abstract={ During October, satellite measurements show that there is a region of elevated tropospheric ozone over the tropical southern Atlantic Ocean. The cause of the high ozone concentrations has been related to biomass burning in South America and Africa. In this paper, we present evidence from satellite sources, European Center for Medium-Range Weather Forecast analyses, and a mesoscale simulation during October, suggesting that afternoon and evening deep convection in central Africa is responsible for some of the abnormally high concentrations of ozone in the tropical South Atlantic which extend southeast over southern Africa into the Indian Ocean. The mechanisms for enhancing tropospheric O/sub 3/ includes (1) the removal of ozone, NO/sub x/, and hydrocarbon rich air from fires in eastern Africa within the planetary boundary layer to the middle and upper troposphere by deep convection; (2) the production of NO/sub x/ from lightning associated with mesoscale convective systems and the subsequent photochemical production of O/sub 3/, and (3) the entrainment of O/sub 3/ rich air from the lower stratosphere into the upper troposphere by deep convection. During the next few years an international field campaign in central Africa (the experiment for regional sources and sinks of oxidants-EXPRESSO), global lightning data, and the launch of the Tropical Rainfall Measuring Mission (TRMM) will help to identify the relative importance of each of the processes over central Africa that could be responsible for high O/sub 3/ concentrations over the tropical south Atlantic }, keywords={ air pollution atmospheric boundary layer atmospheric chemistry atmospheric composition atmospheric movements lightning ozone convective processes Zaire-Congo Basin southern hemispheric ozone maximum tropical southern Atlantic Ocean biomass burning South America Africa mesoscale simulation Indian Ocean NO/sub x/ hydrocarbon rich air fires planetary boundary layer troposphere lightning mesoscale convective systems photochemical production entrainment stratosphere EXPRESSO Tropical Rainfall Measuring Mission TRMM O/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ThompsonJun97, author={Thompson, A.M. and Wei-Kuo Tao and Pickering, K.E. and Scala, J.R. and Simpson, J.}, title={ Tropical deep convection and ozone formation }, journal={Bulletin of the American Meteorological Society}, volume={78}, number={6}, year={1997}, month={Jun}, pages={1043-54}, abstract={ Theoretical studies, aircraft, and space-borne measurements show that deep convection can be an effective conduit for introducing reactive surface pollutants into the free troposphere. Field observations of cloud and mesoscale phenomena have been investigated with the Goddard Cumulus Ensemble and Tropospheric Chemistry models. Case studies from the tropical ABLE 2, STEP, and TRACE-A experiments show that free tropospheric ozone formation should increase when deep convection and urban or biomass burning pollution coincide, and decrease slightly in regions relatively free of ozone precursors (often marine). Confirmation of post-convective ozone enhancement in the free troposphere over Brazil, the Atlantic, and southern Africa was a major accomplishment of the September-October 1992 TRACE-A (Transport and Atmospheric Chemistry near the Equator-Atlantic) aircraft mission. A flight dedicated to cloud outflow showed that deep convection led to a factor of 3-4 increase in upper tropospheric ozone formation downwind. Analysis of ozonesondes during TRACE-A was consistent with 20%-30% of seasonally enhanced ozone over the South Atlantic being supplied by a combination of biomass burning emissions, lightning, and deep convection over South America. With the tropics the critical region for troposphere-to-stratosphere transfer of pollutants, these results have implications for the total ozone budget. Cloud-scale analyses guide the development of more realistic regional and global chemical-transport models to assess the full impact of deep convection on atmospheric chemical composition }, keywords={ air pollution atmospheric composition atmospheric movements clouds ozone stratosphere troposphere tropical deep convection troposphere-to-stratosphere transport ozone formation reactive surface pollutants free troposphere cloud phenomena mesoscale phenomena Goddard Cumulus Ensemble Tropospheric Chemistry ABLE 2 STEP TRACE-A urban pollution biomass burning Brazil Atlantic southern Africa Transport and Atmospheric Chemistry near the Equator-Atlantic cloud outflow South Atlantic lightning South America O/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PaskoJul97, author={Pasko, V.P. and Inan, U.S. and Bell, T.F.}, title={ Sprites as evidence of vertical gravity wave structures above mesoscale thunderstorms }, journal={Geophysical Research Letters}, volume={24}, number={14}, year={1997}, month={Jul}, pages={1735-8}, abstract={ Large area multicell thunderstorms lead to the formation of vertically oriented cylindrical structures of gravity waves at mesospheric altitudes closely resembling those observed in optical emissions associated with transient luminous glows called sprites }, keywords={ atmospheric movements gravity waves lightning mesosphere thunderstorms lightning mesosphere middle atmosphere movement gravity wave vertically oriented cylindrical structure sprite sprites vertical gravity wave structure mesoscale thunderstorm optical emission optical emissions transient luminous glow model penetrative convection mesoscale convective complex }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{CummerJul97, author={Cummer, S.A. and Inan, U.S.}, title={ Measurement of charge transfer in sprite-producing lightning using ELF radio atmospherics }, journal={Geophysical Research Letters}, volume={24}, number={14}, year={1997}, month={Jul}, pages={1731-4}, abstract={ Transient high altitude optical emissions referred to as "sprites" are believed to occur as a result of the transfer of large amounts of charge (\100-300 C) from cloud altitudes of 5-10 km to the ground. Using a general subionospheric ELF propagation model, the authors quantitatively interpret magnetic field waveforms of ELF radio atmospherics originating in mid-western U.S. lightning discharges and observed at Stanford (\1800 km range) to determine the temporal variation of the lightning current and thereby measure the charge transfer during the stroke. For 6 sprite-producing lightning current waveforms observed on July 24, 1996, the authors find that 25 to 325 coulombs of charge was transferred during the first 5 ms of the discharges, assuming a 10 km altitude for the initial charge }, keywords={ atmospherics clouds ionospheric electromagnetic wave propagation lightning thunderstorms atmosphere troposphere thunderstorm thundercloud electric current electric charge transfer sprite-producing lightning sprites ELF radio atmospherics transient high altitude optical emission cloud subionospheric ELF propagation model magnetic field waveform United States USA temporal variation lightning current AD 1996 07 24 }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SukhorukovJul97, author={Sukhorukov, A.I. and Stubbe, P.}, title={ On ELF pulses from remote lightnings triggering sprites }, journal={Geophysical Research Letters}, volume={24}, number={13}, year={1997}, month={Jul}, pages={1639-42}, abstract={ ELF waveforms at large distances from strong CG (cloud-to-ground) discharges are evaluated in the framework of Greifinger's night-time propagation model. It is shown that if the CG discharges triggering red sprites involve, as now generally accepted, >/sub \/10/sup 2/ C of charge then they should generate remote ELF atmospherics with considerably larger magnitudes than measured in the upper ELF (>300 Hz) range }, keywords={ atmospherics lightning thunderstorms radiowave emission stratosphere upper atmosphere thermosphere middle atmosphere ELF pulse EM pulse remote lightning sprite triggering discharge ELF waveform cloud-to-ground discharge Greifinger night-time propagation model Greifinger's model red sprites atmospherics thunderstorm }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{NemiroffMay97, author={Nemiroff, R.J. and Bonnell, J.T. and Norris, J.P.}, title={ Temporal and spectral characteristics of terrestrial gamma flashes }, journal={Journal of Geophysical Research}, volume={102}, number={A5}, year={1997}, month={May}, pages={9659-65}, abstract={ The authors have analyzed the Burst and Transient Source Experiment (BATSE) high-resolution timing data for 13 terrestrial gamma flashes (TGFs) to better characterize this newly identified phenomenon, which may be related to atmospheric lightning. They find that the minimum timescale for TGF variability is \25-250 mu s, with 50 mu s near typical. In general, TGFs are spectrally much harder than cosmic gamma ray bursts (GRBs). They additionally find that as with GRBs, individual pulses within a TGF tend to peak earlier at higher energies. This time-asymmetry rules out models such as sweeping beams. They also find that different pulses can have different spectra, with spectra typically softening as a pulse progresses. Event-averaged spectra for the TGFs were examined and found to be better fit in the 25-500 keV range by a power law than by a blackbody model. However, in general, even a power law is not a perfect fit. They find correlation between minimum TGF timescale and the power law spectral index, with rapidly varying TGFs appearing softer. From empirical comparisons of timescales and structures they speculate that if TGFs are somehow related to known high-atmospheric lightning events, then they are more probably related to red sprites than to blue jets or transionospheric pulse pairs }, keywords={ atmospheric radiation gamma-rays lightning mesosphere stratosphere X-rays terrestrial radiation gamma ray emission spectral characteristics terrestrial gamma flash gamma ray flash atmosphere lightning red sprite TGF BATSE temporal characteristics variability time scale gamma ray spectra time-asymmetry pulse profile X-ray emission X-ray pulse model transionospheric pulse pair 25 to 500 keV }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{DowdenApr97, author={Dowden, R.L. and Rodger, C.J.}, title={ A vertical-plasma-slab model for determining the lower limit to plasma density in sprite columns from VLF scatter measurements }, journal={IEEE Antennas and Propagation Magazine}, volume={39}, number={2}, year={1997}, month={Apr}, pages={44-53}, abstract={ VLF to MF backscatter from "red sprites" is investigated by the use of a one-dimensional model, in which the sprite is considered as an infinite vertical slab of plasma. The reflection (backscatter) and transmission (forward-scatter) coefficients are found for a wide range of slab parameters. For a slab in which such parameters vary with altitude, the approximation is made that the scatter coefficients vary with altitude accordingly. A conductivity of 10/sup -4/ S/m is found sufficient to explain the observed magnitudes of backscatter (large angles up to 180 degrees ), provided this or higher conductivity prevails over a substantial part of the cloud-ionosphere altitude range. The effect of the geomagnetic field on the conductivity at altitudes up to 80 km, and wave frequencies up to 10 MHz, is found to be of little consequence }, keywords={ atmospheric electricity backscatter Earth-ionosphere waveguide electromagnetic wave scattering ionospheric disturbances lightning plasma density plasma electromagnetic wave propagation radiowave propagation remote sensing by radar vertical-plasma-slab model plasma density sprite columns VLF scatter measurements MF backscatter red sprites one-dimensional model infinite vertical slab reflection transmission forward-scatter backscatter altitude conductivity geomagnetic field }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MilikhApr97, author={Milikh, G.M. and Valdivia, J.A. and Papadopoulos, K.}, title={ Model of red sprite optical spectra }, journal={Geophysical Research Letters}, volume={24}, number={8}, year={1997}, month={Apr}, pages={833-6}, abstract={ A synthetic spectrum of red sprites due to electron energization by the electric field from lightning is computed by using the electron energy spectrum obtained from a Fokker-Planck code, which includes various inelastic losses. The results are compared with observed sprite spectra. Implications to models of red sprites are presented }, keywords={ airglow atmospheric electricity atmospheric spectra ionosphere lightning mesosphere stratosphere thermosphere thunderstorms theory model middle atmosphere thunderstorm mesosphere visible spectra thermosphere optical emission red sprite optical spectra synthetic spectrum electron energization electric field lightning electron energy spectrum ionosphere Fokker-Planck code inelastic loss airglow }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Roussel-DupreMar97, author={Roussel-Dupre, R.A. and Blanc, E.}, title={ HF echoes from ionization potentially produced by high-altitude discharges }, journal={Journal of Geophysical Research}, volume={102}, number={A3}, year={1997}, month={Mar}, pages={4613-22}, abstract={ The presence of ionization associated with high-altitude discharges has been detected using an HF radar operating at 2.2, 2.5, and 2.8 MHz. On several occasions, oblique echoes lasting several hundred ms at night and 1 to 10 s during the day were observed. The echoes turned on in several interpulse times of 70 ms and were generally correlated with strong lightning activity prior to onset. The angles of arrival of sferics detected at three goniometer stations were used to determine the distance to thunderstorms. The data are consistent with specular reflections from columns of ionization produced at 55-65 km altitude and having minimum electron densities of 6*10/sup 4/-10/sup 5/ cm/sup -3/. The source of the ionization is believed to be high-altitude discharges }, keywords={ atmospheric electricity atmospheric electromagnetic wave propagation atmospheric ionisation ionosphere ionospheric electromagnetic wave propagation lightning mesosphere ionosphere mesosphere middle atmosphere radiowave reflection radar scattering MF HF echo ionization high-altitude electric discharge HF radar oblique echo night day lightning specular reflection radiowave propagation 2.2 MHz 2.5 MHz 2.8 MHz 55 to 65 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PaskoMar97, author={Pasko, V.P. and Inan, U.S. and Bell, T.F. and Taranenko, Y.N.}, title={ Sprites produced by quasi-electrostatic heating and ionization in the lower ionosphere }, journal={Journal of Geophysical Research}, volume={102}, number={A3}, year={1997}, month={Mar}, pages={4529-61}, abstract={ Quasi-electrostatic (QE) fields that temporarily exist at high altitudes following the sudden removal (e.g., by a lightning discharge) of thundercloud charge at low altitudes lead to ambient electron heating (up to \5 eV average energy), ionization of neutrals, and excitation of optical emissions in the mesosphere/lower ionosphere. Model calculations predict the possibility of significant (several orders of magnitude) modification of the lower ionospheric conductivity in the form of depletions of electron density due to dissociative attachment to O$_2$ molecules and/or in the form of enhancements of electron density due to breakdown ionization. Results indicate that the optical emission intensities of the 1st positive band of N$_2$ corresponding to fast (\1 ms) removal of 100-300 degrees C of thundercloud charge from 10 km altitude are in good agreement with observations of the upper part ("head" and "hair" [Sentman et al., 1995]) of the sprites. The typical region of brightest optical emission has horizontal and vertical dimensions \10 km, centered at altitudes 70 km and is interpreted as the head of the sprite. The model also shows the formation of low intensity glow ("hair") above this region due to the excitation of optical emissions at altitudes \85 km during \500 mu s at the initial stage of the lightning discharge. Comparison of the optical emission intensities of the 1st and 2nd positive bands of N$_2$, Meinel and 1st negative bands of N$_2$/sup +/ and 1st negative band of O/sub 2//sup +/ demonstrates that the 1st positive band of N$_2$ is the dominating optical emission in the altitude range around \70 km, which accounts for the observed red color of sprites, in excellent agreement with recent spectroscopic observations of sprites. Results indicate that the optical emission levels are predominantly defined by the lightning discharge duration and the conductivity properties of the atmosphere/lower ionosphere (i.e., relaxation time of electric }, keywords={ airglow atmospheric ionisation ionosphere ionospheric disturbances lightning mesosphere stratosphere thunderstorms thunderstorm lightning mesosphere ionosphere optical emission airglow middle atmosphere quasi-electrostatic heating sprite ionization electron heating model calculation breakdown ionization ionospheric disturbance thundercloud charge head hair red color }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LyonsDec96, author={Lyons, W.A.}, title={ Sprite observations above the U.S. High Plains in relation to their parent thunderstorm systems }, journal={Journal of Geophysical Research}, volume={101}, number={D23}, year={1996}, month={Dec}, pages={29641-52}, abstract={ Transient luminous events (sprites, blue jets, elves) above large mesoscale convective systems (MCSs) over the U.S. High Plains have been routinely monitored from the Yucca Ridge Field Station near Fort Collins, Colorado using ground-based low-light video systems. The author analyzed 36 sprites above the Nebraska MCS of August 6, 1994. The results lend further support to the hypothesis that sprites are almost uniquely associated with positive cloud-to-ground lightning flashes (+CGs). Sprite-associated +CGs also averaged substantially larger peak currents than the remaining +CG population (81 kA versus 30 kA in this storm system). There is some evidence that sprite-associated +CGs also have higher stroke multiplicity. This study yields no evidence of sprites associated with negative CG events. In the central United States an additional requirement appears to be that the parent MCS has a contiguous radar reflectivity area exceeding 20-25,000 km/sup 2/. The majority of the sprites occur above the large stratiform precipitation region and not the high-reflectivity convective core of the MCS. Triangulation of a limited number of paired images (from September 7, 1994) suggests that the sprite is generally centered within 50 km of the parent +CG. Assuming the +CG provides the range, single-image photogrammetric analyses provide estimates of the maximum vertical extent of the sprites. For this storm the sprite tops averaged 77 km with a maximum of 88 km. The bases averaged 50 km but with a few sprite tendrils extending as low as 31 km }, keywords={ lightning thunderstorms sprite observations US High Plains thunderstorm systems transient luminous events blue jets elves large mesoscale convective systems Yucca Ridge Field Station Fort Collins Colorado USA ground-based low-light video systems Nebraska AD 1994 08 06 positive cloud-to-ground lightning flashes peak currents stroke multiplicity central United States radar reflectivity area stratiform precipitation region AD 1994 09 07 single-image photogrammetric analyses maximum vertical extent sprite tendrils sprite top heights 81 kA 77 to 88 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{FullekrugDec96, author={Fullekrug, M. and Reising, S.C. and Lyons, W.A.}, title={ On the accuracy of arrival azimuth determination of sprite-associated lightning flashes by Earth-ionosphere cavity resonances }, journal={Geophysical Research Letters}, volume={23}, number={25}, year={1996}, month={Dec}, pages={3691-4}, abstract={ Horizontal magnetic field variations in the frequency range of the Earth-ionosphere cavity resonances are observed at Silberborn, Germany, simultaneous with 19 sprite-associated lightning flashes in the midwestern United States, on July 15, 1995. The measured horizontal magnetic intensities are linearly related to the horizontal magnetic intensities of slow tails of radio atmospherics which were simultaneously recorded at Palmer Station, Antarctica. Enhancement of the Earth-ionosphere cavity resonances is verified by spectral analysis, and the measured arrival azimuths are in agreement with the expected orientation of the Poynting vector along the great-circle path. The estimated accuracy of the arrival azimuth determination is on the order of +or-5 degrees }, keywords={ atmospherics Earth-ionosphere waveguide lightning sprite-associated lightning flashes arrival azimuth determination Earth-ionosphere cavity resonances horizontal magnetic field variations Silberborn Germany AD 1995 07 15 horizontal magnetic intensities radio atmospherics Palmer Station Antarctica spectral analysis Poynting vector orientation great-circle path }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{WescottDec96, author={Wescott, E.M. and Sentman, D.D. and Heavner, M.J. and Hallinan, T.J. and Hampton, D.L. and Osborne, D.L.}, title={ The optical spectrum of aircraft St. Elmo's fire }, journal={Geophysical Research Letters}, volume={23}, number={25}, year={1996}, month={Dec}, pages={3687-90}, abstract={ On February 26, 1995, during a NASA sponsored mission to Peru to study red sprites and blue jets, the instrumented Westwind 2 jet aircraft encountered spectacular St. Elmo's fire from the wing pods, tail and nose while flying through a cloud at an altitude of 13.83 km (45376 ft). The phenomenon was captured on low light level monochromatic and color television systems aboard the aircraft, and its spectrum was recorded on a low light level TV spectrograph with response from 395.0 to 750.0 nm. The cameras and spectrograph also recorded scattered intra-cloud lightning and a possible lightning discharge near, or to, the aircraft. The spectrum of St. Elmo's fire was primarily the second (2nd) positive bands of N$_2$. The data were consistent with a population of electrons having relatively low energy (<18 eV) }, keywords={ aircraft atmospheric electricity atmospheric spectra clouds lightning television applications aircraft St. Elmo's fire optical spectrum AD 1995 02 26 instrumented Westwind 2 jet aircraft cloud low light level monochromatic TV system colour TV systems low light level TV spectrograph scattered intracloud lightning lightning discharge N$_2$ second positive bands low energy electron population 13.83 km 395 to 750 nm N$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ReisingDec96, author={Reising, S.C. and Inan, U.S. and Bell, T.F. and Lyons, W.A.}, title={ Evidence for continuing current in sprite-producing cloud-to-ground lightning }, journal={Geophysical Research Letters}, volume={23}, number={24}, year={1996}, month={Dec}, pages={3639-42}, abstract={ Radio atmospherics launched by sprite-producing positive cloud-to-ground lightning flashes and observed at Palmer Station, Antarctica, exhibit large ELF slow tails following the initial VLF portion, indicating the presence of continuing currents in the source lightning flashes. One-to-one correlation of sferics with NLDN lightning data in both time and arrival azimuth, measured with an accuracy of +or-1 degrees at \12,000 km range, allows unambiguous identification of lightning flashes originating in the storm of interest. Slow-tail measurements at Palmer can potentially be used to measure continuing currents in lightning flashes over nearly half of the Earth's surface }, keywords={ atmospherics lightning thunderstorms atmosphere troposphere electric field electric current continuing current sprite-producing cloud-to-ground lightning thunderstorm atmospherics positive cloud-to-ground lightning flash Palmer Station Antarctica large ELF slow tail source lightning flash sferics NLDN lightning }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ZhengDec96, author={Zheng, J. and Weinheimer, A.J. and Ridley, B.A. and Liu, S.C. and Sachse, G.W. and Anderson, B.H. and Collins, J.H., Jr.}, title={ Analysis of small- and large-scale increases of reactive nitrogen observed during the Second Airborne Arctic Stratospheric Expedition }, journal={Journal of Geophysical Research}, volume={101}, number={D22}, year={1996}, month={Dec}, pages={28805-16}, abstract={ An analysis of the data obtained during AASE II was made to characterize small- ( delta x<24 km) and large-scale (30< delta x<260 km) increases of reactive nitrogen species. By using the NO/sub x//NO/sub y/ ratio, the increases were classified into fresh emissions and aged air parcels. The sources of the NO/sub y/ increases were then assessed by the freshness of the increases and by examining the correlation (or absence thereof) between NO/sub y/ and other trace species including tracers of various NO/sub x/ sources: for example, aircraft emissions, lightning, the stratospheric source, and sources in the boundary layer. The authors found that the majority (43%) of NO/sub y/ increases in the upper troposphere and lower stratosphere were due to displacement of constant mixing ratio surfaces relative to isobaric flight paths. Aircraft emissions were the second most abundant (17%). The next significant contributor was surface emissions, including fossil fuel combustion and biomass burning. Only two lightning spikes were found, apparently due to the winter season and emphasis on high latitudes in the AASE II experiment. The relative contribution from each source to the increases (or positive variability) represents a measure of the relative source strength. However, it is important to note that the authors' findings on the relative contribution of each source to the increases should not be applied directly to estimating the relative source strength of the ambient or background NO/sub y/ abundance. Knowledge of the detailed temporal and spatial distribution of the relative contribution of each source is needed. This requires a substantially higher precision for the instruments of tracer gases than those used in this study }, keywords={ air pollution atmospheric composition nitrogen compounds stratosphere polar atmosphere Arctic stratosphere air pollution chemical composition large-scale increase Airborne Arctic Stratospheric Expedition AASE II NO/sub x/ NO/sub y/ fresh emissions aged air parcel spatial distribution abundance NO NO$_2$ N$_2$O }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{DowdenAug96, author={Dowden, R.L. and Brundell, J.B. and Lyons, W.A.}, title={ Are VLF rapid onset, rapid decay perturbations produced by scattering off sprite plasma? }, journal={Journal of Geophysical Research}, volume={101}, number={D14}, year={1996}, month={Aug}, pages={19175-83}, abstract={ Rapid onset, rapid decay perturbations (RORDs) of subionospheric VLF propagation require highly localized or laterally structured plasma at low altitudes to explain the wide angle scattering observed and the rapid decay. Simultaneous occurrence of RORDs and red sprites, illustrated by a single event, together with VLF phase and group delay measurements from a pair of spaced receivers suggest that RORDs are produced by scattering from conducting columns at the position and with the lateral shape of the sprite. The sprite luminosity decays much faster than the RORDs which depend on the sprite conductivity and so plasma density. Plasma is also produced near the sprite plasma by energetic electrons precipitated from the magnetosphere by ducted whistlers and after the expected whistler and electron propagation delay. This whistler-induced electron precipitation (WEP) plasma produces wide angle VLF scattering similar to that by sprite plasma, implying similar lateral fine structure. This suggests that the processes leading to sprites also produce whistler ducts in the magnetosphere }, keywords={ atmospheric electromagnetic wave propagation Earth-ionosphere waveguide ionospheric disturbances ionospheric electromagnetic wave propagation lightning mesosphere stratosphere VHF radio propagation stratosphere mesosphere radiowave propagation VLF rapid onset rapid decay perturbation RORD red sprite sprite plasma ionosphere magnetosphere middle atmosphere subionospheric propagation highly localized plasma laterally structured plasma lateral variation low altitude wide angle scattering phase delay group delay electron precipitation ducted whistler electron propagation delay lateral fine structure }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{GurevichNov96, author={Gurevich, A.V. and Valdivia, J.A. and Milikh, G.M. and Papadopoulos, K.}, title={ Runaway electrons in the atmosphere in the presence of a magnetic field }, journal={Radio Sci. (USA), Radio Science}, volume={31}, number={6}, year={1996}, month={Nov}, pages={1541-54}, abstract={ This paper generalizes the theory of the electron runaway and runaway discharge to the case of a laminar electric field at an arbitrary angle to the magnetic field and derives the relevant threshold conditions. It is shown that the conditions of the runaway process depend on the angle between the electric and magnetic fields, and the ratio of their magnitudes. In fact, the geomagnetic field hinders the development of runaway breakdown in the atmosphere. This effect has implications for runaway discharges in the atmosphere caused by low-altitude lightning. The runaway discharges manifest themselves as fluxes of gamma -rays, as previously observed by the detector aboard Compton Gamma Ray Observatory. The geomagnetic field plays a significant role in the runaway discharge due to thunderstorms for heights above 20 km, where the cyclotron frequency of relativistic electrons exceeds their collision frequency. This effect depends on the angle between the electric and magnetic fields. Since the static electric fields from thunderclouds are directed almost vertically, one can expect a significant difference in the properties of high-altitude discharges occurring at equatorial and high-latitude regions }, keywords={ atmospheric ionisation atmospheric radiation geomagnetism lightning stratosphere thunderstorms runaway electrons atmosphere magnetic field electron runaway runaway discharge laminar electric field threshold conditions geomagnetic field runaway breakdown low-altitude lightning gamma rays thunderstorms cyclotron frequency relativistic electrons collision frequency high-altitude discharges 0 to 40 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{JacobOct96, author={Jacob, D.J. and Heikes, B.G. and Fan, S.-M. and Logan, J.A. and Mauzerall, D.L. and Bradshaw, J.D. and Singh, H.B. and Gregory, G.L. and Talbot, R.W. and Blake, D.R. and Sachse, G.W.}, title={ Origin of ozone and NO/sub x/ in the tropical troposphere: a photochemical analysis of aircraft observations over the South Atlantic basin }, journal={Journal of Geophysical Research}, volume={101}, number={D19}, year={1996}, month={Oct}, pages={24235-50}, abstract={ The photochemistry of the troposphere over the South Atlantic basin is examined by modeling of aircraft observations up to 12-km altitude taken during the TRACE A expedition in September-October 1992. A close balance is found in the 0 to 12-km column between photochemical production and loss of O/sub 3/, with net production at high altitudes compensating for weak net loss at low altitudes. This balance implies that O/sub 3/ concentrations in the 0-12 km column can be explained solely by in situ photochemistry; influx from the stratosphere is negligible. Simulation of H$_2$O$_2$, CH/sub 3/OOH, and CH$_2$O concentrations measured aboard the aircraft lends confidence in the computations of O/sub 3/ production and loss rates, although there appears to be a major gap in current understanding of CH/sub 2/O chemistry in the marine boundary layer. The primary sources of NO/sub x/ over the South Atlantic Basin appear to be continental (biomass burning, lightning, soils). There is evidence that NO/sub x/ throughout the 0 to 12-km column is recycled from its oxidation products rather than directly transported from its primary sources. There is also evidence for rapid conversion of HNO/sub 3/ to NO/sub x/ in the upper troposphere by a mechanism not included in current models. A general representation of the O/sub 3/ budget in the tropical troposphere is proposed that couples the large-scale Walker circulation and in situ photochemistry. Deep convection in the rising branches of the Walker circulation injects NO/sub x/ from combustion, soils, and lightning to the upper troposphere, leading to O/sub 3/ production; eventually, the air subsides and net O/sub 3/ loss takes place in the lower troposphere, closing the O/sub 3/ cycle. This scheme implies a great sensitivity of the oxidizing power of the atmosphere to NO/sub x/ emissions in the tropics }, keywords={ air pollution atmospheric boundary layer atmospheric chemistry atmospheric composition nitrogen compounds ozone troposphere atmosphere chemistry photochemistry air pollution ozone AD 1992 09 AD 1992 10 tropical troposphere photochemical analysis aircraft observations South Atlantic basin model photochemical production and loss marine boundary layer biomass burning lightning 0.1 to 12 km O/sub 3/ NO NO$_2$ HNO/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{KrausAug96, author={Kraus, A.B. and Rohrer, F. and Grobler, E.S. and Ehhalt, D.H.}, title={ The global tropospheric distribution of NO/sub x/ estimated by a three-dimensional chemical tracer model }, journal={Journal of Geophysical Research}, volume={101}, number={D13}, year={1996}, month={Aug}, pages={18587-604}, abstract={ The global distribution of NO/sub x/ in the troposphere is calculated using a simple three-dimensional chemical tracer model. This model includes a simplified chemistry scheme for the tracers NO/sub x/ identical to NO+NO$_2$ and HNO/sub 3/, which are redistributed by advection, dry and wet convection, and large-scale diffusion. The sources of NO/sub x/ considered are fossil fuel combustion, emissions from soil microbial activity, biomass burning, lightning discharges, emissions by aircraft, and downward transport from the stratosphere. Dry and wet deposition act as final sinks. At northern middle and high latitudes the calculated tropospheric NO/sub x/ content is dominated by the surface sources, fossil fuel combustion in particular. In the tropical free troposphere, lightning discharges provide about 80% of the total NO/sub x/ throughout the year. The zonally averaged fractional contribution of aircraft emissions strongly depends on the season. The largest contribution of this source, over 60%, occurs during January in the upper troposphere between 45 degrees N and 60 degrees N. The NO mixing ratios determined by the model show good overall agreement with vertical profiles measured during the Stratospheric Ozone Experiment (STRATOZ) III aircraft campaign }, keywords={ air pollution atmospheric composition hydrogen compounds nitrogen compounds troposphere atmosphere troposphere chemical composition air pollution global distribution three-dimensional chemical tracer model advection wet convection large-scale diffusion fossil fuel combustion soil gas biomass burning lightning vertical profile NO NO$_2$ HNO/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{WescottAug96, author={Wescott, E.M. and Sentman, D.D. and Heavner, M.J. and Hampton, D.L. and Osborne, D.L. and Vaughan, O.H., Jr.}, title={ Blue starters: brief upward discharges from an intense Arkansas thunderstorm }, journal={Geophysical Research Letters}, volume={23}, number={16}, year={1996}, month={Aug}, pages={2153-6}, abstract={ Documents the first observations of a new stratospheric electrical phenomenon associated with thunderstorms. On the night of 30 June (UT 1 July) 1994, 30 examples of these events, which the authors have called "blue starters," were observed in a 6 m 44 s interval above the very energetic Arkansas thunderstorm where blue jets were first observed. The blue starters are distinguished from blue jets by a much lower terminal altitude. They are bright and blue in color, and protrude upward from the cloud top (17-18 km) to a maximum 25.5 km (83,655 ft.) in altitude. All blue starters events were recorded from two small areas near Texarkana, Texas/Arkansas where hail 7.0 cm in diameter was falling. Comparison to cloud-to-ground (CG) lightning flashes revealed: 1. Blue starters were not observed to be coincident with either positive or negative CG flashes, but they do occur in the same general area as negative CG flashes; 2. Cumulative distributions of the negative CG flashes in +or-5 s before and after the starter and within a radius of 50 km shows a significant reduction for about 3 s following the event in the two cells where starters and jets were observed. The energy deficit is approximately 10/sup 9/ J. It is possible that blue starters are a short-lived streamer phenomenon }, keywords={ atmospheric electricity lightning stratosphere thunderstorms stratosphere atmosphere optical emission United States USA thunderstorm lightning blue starter brief upward discharge intense Arkansas thunderstorm electrical phenomenon electric discharge blue starters terminal altitude AD 1994 06 30 blue colour Texarkana Texas hail cloud-to-ground lightning energy deficit short-lived streamer phenomenon }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{GreenAug96, author={Green, B.D. and Fraser, M.E. and Rawlins, W.T. and Jeong, L. and Blumberg, W.A.M. and Mende, S.B. and Swenson, G.R. and Hampton, D.L. and Wescott, E.M. and Sentman, D.D.}, title={ Molecular excitation in sprites }, journal={Geophysical Research Letters}, volume={23}, number={16}, year={1996}, month={Aug}, pages={2161-4}, abstract={ We have determined the molecular internal energy distribution in the N/sub 2/ B/sup 3/ Pi /sub g/ state from the fluorescence measured during the observations of sprites during 1995. Spectrally resolved data from two different instruments and three different sprites are compared with theoretical spectra to obtain excited state vibrational distributions. Energy dependent electron excitation cross-sections and laboratory data were used to estimate the energies of electrons producing the red sprite radiance. Implications for chemical production in the mesosphere and critical future measurements are discussed }, keywords={ atmospheric chemistry atmospheric radiation excited states fluorescence lightning nitrogen vibrational states visible spectra molecular excitation sprites molecular internal energy distribution N$_2$ B/sup 3/ Pi /sub g/ state fluorescence excited state vibrational distributions energy dependent electron excitation cross-sections red sprite radiance chemical production mesosphere AD 1995 N$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Seliga96, author={Seliga, T.A. and Sahr, J.D. and Holzworth, R.H.}, title={ Probing electric fields near sprites and jets using multiparameter radar and chaff }, booktitle={IGARSS '96. 1996 International Geoscience and Remote Sensing Symposium.Remote Sensing for a Sustainable Future (Cat. No.96CH35875)}, volume={}, number={}, year={1996}, month={}, pages={569-73 vol.1}, abstract={ The discovery of electric discharges above thunderstorms has generated intense scientific interest. Studies of these sprites' and jets' have focused on their characterization by optical and radio techniques, with radar measurements of the causative storms providing insight into related weather. The authors describe a method for investigating the electric field structure above thunderstorms using ground-based radar to observe chaff dispersed by rockets. Slender conducting or dielectric chaff will generally align itself with the ambient electric field. This alignment is readily detected by appropriate configurations of polarimetric radar(s) such as are now used in meteorology to observe the nature and motion of hydrometeors. This is especially convenient as it permits the thunderstorms associated with sprites and jets to be characterized with the same experimental facility. This paper renders a preliminary examination of factors such experiments would entail and features that a multiparameter radar might utilize to probe chaff dispersed by small rockets. Monostatic and bistatic radar measurements of scatter from chaff provide a powerful tool to study electric fields associated with sprites and jets as well as other atmospheric electric fields }, keywords={ atmospheric electricity atmospheric techniques lightning mesosphere meteorological radar radar polarimetry remote sensing by radar stratosphere thunderstorms middle atmosphere stratosphere mesosphere radar remote sensing measurement technique electric field storm thunderstorm lightning sprite optical emission optical jet multiparameter radar chaff electric discharge dielectric chaff alignment polarimetric radar red sprite blue jet }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SukhorukovJun96, author={Sukhorukov, A.I. and Mishin, E.V. and Stubbe, P. and Rycroft, M.J.}, title={ On blue jet dynamics }, journal={Geophysical Research Letters}, volume={23}, number={13}, year={1996}, month={Jun}, pages={1625-8}, abstract={ A model is proposed for blue jets [Sentman and Wescott, 1995; Wescott et al., 1995], which explains their dynamics, in particular the jet vertical velocity of about 100 km/s, the terminal altitudes of about 40-50 km, and the competitive occurrence of blue jets and the recently discovered blue starters [Wescott et al., 1995]. A blue jet is considered to be formed by an attachment-controlled ionizing wave, which moves upward via an electron avalanche in the wavefront due to the mainly vertical, downward directed quasi-electrostatic field, caused by the extraordinarily large (>100 degrees C) charge transfer in a high-altitude intracloud discharge or in a positive cloud-to-ground discharge with a long continuing current }, keywords={ airglow atmospheric electricity atmospheric ionisation lightning mesosphere stratosphere thunderstorms stratosphere thunderstorm optical emission mesosphere middle atmosphere blue jet dynamics sprite lightning positive cloud-to-ground discharge model vertical velocity terminal altitude occurrence blue starter blue starters attachment-controlled ionizing wave electron avalanche ionisation ionization wavefront downward directed quasi-electrostatic field electric field electric discharge charge transfer high-altitude intracloud discharge 20 to 50 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanApr96, author={Sentman, D.D.}, title={ Schumann resonance spectra in a two-scale-height Earth-ionosphere cavity }, journal={Journal of Geophysical Research}, volume={101}, number={D5}, year={1996}, month={Apr}, pages={9479-87}, abstract={ New expressions are developed for the amplitude and power spectra of the electric and magnetic components of lightning-excited Schumann resonances. A classical normal mode approach is used, yielding expressions directly in terms of the complex eigenfrequencies of the Earth-ionosphere cavity. Using previous simplified formulations of the eigenvalue problem in terms of a two-scale-height model of a dissipative Earth-ionospheric cavity, these results permit calculation of spectra in terms of geometric properties of the system. The expressions are in a convenient form for application in correlation studies involving use of the resonance intensities as a proxy measure of other Earth system parameters, such as average tropical continental temperature }, keywords={ Earth-ionosphere waveguide lightning Schumann resonance spectra Earth-ionosphere cavity amplitude power spectra electric component magnetic component lightning-excited Schumann resonances classical normal mode approach complex eigenfrequencies eigenvalue problem two-scale-height model dissipative Earth geometric properties resonance intensities Earth system parameters average tropical continental temperature }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @TECHREPORT{KohlerFeb96, author={Kohler, I. and Sausen, R. and Reinberger, R.}, title={ Contributions of aircraft emissions to the atmospheric NO/sub x/ content }, journal={}, institution={}, year={1996}, pages={ 33}, abstract={ The relative contribution of aircraft emissions to the total atmospheric NO/sub x/ content is studied by means of the atmosphere general circulation model ECHAM, which was extended by a simplified (linear) NO/sub x/ chemistry module with NO/sub x/ and HNO/sub 3/ as prognostic variables. NO/sub x/ originates from fossil fuel combustion, biomass burning, soil microbial activity, lightning, degradation of N$_2$O in the stratosphere, and aircraft emissions. NO$_2$ and HNO/sub 3/ are removed by dry deposition, HNO/sub 3/ additionally by wet deposition. A simulation in seasonal cycle mode was performed. Both, the resulting January and July mean distributions of NO/sub x/ and the relative contributions of the different sources to the total atmospheric NO/sub x/ burden are analysed, including their uncertainty ranges. NO/sub x/ emissions from aircraft cause a significant change to the background NO/sub x/ concentration. During January more than 60% of the NO/sub x/ emissions found in the region between 30 degrees N and 60 degrees N, and 175 hPa to 325 hPa arise from aircraft. The maximum value in the North Atlantic flight corridor is found to be larger than 85%. During July aircraft emissions contribute only about 20% to the NO/sub x/ burden in this region. In January and July the uncertainty ranges of these contributions are 42% to 80% and 10% to 37%, respectively }, keywords={ air pollution aircraft atmospheric chemistry atmospheric composition nitrogen compounds aircraft emissions troposphere general circulation model atmospheric chemistry seasonal cycle concentration fossil fuel combustion ECHAM3 model lightning soil microbial activity biomass burning sources sinks maps stratosphere altitude versus latitude NO/sub x/ HNO/sub 3/ }, } /usr/tmp/citation.tmp.27694 @ARTICLE{PaskoMar96, author={Pasko, V.P. and Inan, U.S. and Bell, T.F.}, title={ Sprites as luminous columns of ionization produced by quasi-electrostatic thundercloud fields }, journal={Geophysical Research Letters}, volume={23}, number={6}, year={1996}, month={Mar}, pages={649-52}, abstract={ Quasi-electrostatic (QE) fields which exist above thunderclouds after lightning discharges can lead to the formation of columnar channels of breakdown ionization and carrot-like vertical luminous structures with typical transverse dimension À5-10 km spanning an altitude range from À80 km to well below À50 km. The carrot-like forms closely resemble those observed in sprites. Results indicate that the appearance of optical emissions can be significantly delayed in time (À1-20 ms) with respect to the causative lightning discharge }, keywords={ airglow atmospheric electricity atmospheric ionisation lightning mesosphere thermosphere thunderstorms middle atmosphere mesosphere upper atmosphere thermosphere stratosphere ionisation ionization sprite thunderstorm disturbance optical emission electric discharge luminous column quasi-electrostatic field electric field lightning columnar channel breakdown ionization carrot-like vertical luminous structure delay }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{InanMar96, author={Inan, U.S. and Slingeland, A. and Pasko, V.P. and Rodriguez, J.V.}, title={ VLF and LF signatures of mesospheric/lower ionospheric response to lightning discharges }, journal={Journal of Geophysical Research}, volume={101}, number={A3}, year={1996}, month={Mar}, pages={5219-38}, abstract={ New evidence is presented of disturbances of the electrical conductivity of the nighttime mesosphere and the lower ionosphere in association with lightning discharges. In addition to extensive documentation of the characteristics of a class of events heretofore referred to as early/fast VLF events, Inan et al. (1993), the present authors data reveal a new feature of these events, consisting of a postonset peak that typically lasts for 1-2 s. They also report the observation of short-duration VLF or LF perturbations, in which the amplitude of the subionospheric signal exhibits a sudden change within 20 ms of the causative lightning discharge, and recovers back to its original level in <3 s. These short-duration events have characteristics similar to the previously observed rapid onset, rapid decay VLF signatures, Doulden et al. (1994). Both the typical and rapidly recovering events are observed primarily when the causative lightning discharge is within +or-50 km of the VLF or LF great circle propagation path, indicating that the scattering from the localized disturbance is highly collimated in the forward direction. The latter in turn implies that for the parameters in hand, the transverse extent of the disturbance must be at least À100-150 km. The measured VLF signatures are compared with the predictions of a three-dimensional model of subionospheric VLF propagation and scattering in the presence of localized ionospheric disturbances produced by electromagnetic impulses and quasi-electrostatic QE fields produced by lightning discharges. The rapidly recovering or short-duration events are consistent with the heating of the ambient electrons by quasi-static electric fields, in cases when heating is not intense enough to exceed-the attachment or ionization thresholds. When no significant electron density changes occur, the conductivity changes due to heating alone last only as long as the QE fields, typically less than a few seconds. When heating is intense enough so t }, keywords={ atmospheric electricity atmospheric electromagnetic wave propagation atmospherics ionospheric disturbances ionospheric electromagnetic wave propagation lightning mesosphere atmospherics radiowave emission thunderstorm VLF signature LF signature mesosphere lower ionosphere response middle atmosphere ionospheric disturbance lightning electric discharge electrical conductivity night postonset peak short-duration perturbation short-duration events radiowave propagation }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{WincklerMar96, author={Winckler, J.R. and Lyons, W.A. and Nelson, T.E. and Nemzek, R.J.}, title={ New high-resolution ground-based studies of sprites }, journal={Journal of Geophysical Research}, volume={101}, number={D3}, year={1996}, month={Mar}, pages={6997-7004}, abstract={ New observations of sprites (cloud-ionosphere luminous discharges above thunderstorms) were made from the Yucca Ridge Field Station 20 km northeast of Fort Collins, Colorado, on the night of July 11-12, 1994, as part of a summer 1994 observing campaign. The sprites appeared above a moderate mesoscale convective complex mostly over Kansas at a range of about 270 km. The sprites were observed with both wide-field and telescopic image-intensified CCD TV cameras, a telescopic photometer system, and a 1- to 50-kHz band VLF sferics receiver. This paper is based on five 1-s data intervals containing bright sprites, smaller sprites, and cloud and sky flashes. Telescopic TV images of bright sprites had a fan-shaped upper plume with very fine features not well resolved by the TV, but dendritic (upward forked) and vertically striated forms adjacent to these plumes and bright points of luminosity around the plume-shaped regions. Many sprites consisted entirely of groups of vertically aligned striations which sometimes appeared to diverge from a common point of origin at cloud tops. All sprites in the present data sample were preceded by a cloud to ground (CG) stroke with a coincident sferic and sky flash. All CG strokes associated with sprites were positive, and most were 100 kA or more inferred peak current. From the photometer, the duration of the CG-induced sky flashes was about 3 ms and the additional sprite total light curve was also about 3 ms. The puzzling feature that the total duration of TV images of sprites was often longer than the photometric values is discussed and an explanation given. The sprites were attributed to strong negative charging, following the positive CG stroke, of a localized cloud top region which produced an intense electric field and a luminous discharge in the cloud-ionosphere region. The concept of "break-even" electric fields suggested by McCarthy and Parks may explain discharge initiation with moderate field strengths }, keywords={ airglow atmospheric electricity lightning mesosphere stratosphere thermosphere thunderstorms United States USA middle atmosphere stratosphere mesosphere thermosphere upper atmosphere electric discharge thunderstorm lightning sprite airglow Yucca Ridge Field Station AD 1994 07 Colorado mesoscale convective complex Kansas optical emission morphology fan-shaped upper plume vertically aligned striation strong negative charging }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MarshallMar96, author={Marshall, T.C. and Stolzenburg, M. and Rust, W.D.}, title={ Electric field measurements above mesoscale convective systems }, journal={Journal of Geophysical Research}, volume={101}, number={D3}, year={1996}, month={Mar}, pages={6979-96}, abstract={ The authors show that electric field discontinuities occur above the stratiform clouds associated with mesoscale convective systems. Above cloud top, 12 discontinuities were observed at altitudes between 10 and 16 km. The field changes of the discontinuities ranged from -1.1 to -4.0 kV m/sup -1/. The data suggest that the electric field discontinuities were caused by coincident, positive, cloud-to-ground lightning flashes. The coincident ground flashes included both single and multiple return stroke flashes, with first-stroke peak currents between 20 and 154 kA. The authors modeled the electric field change that would occur if lightning discharged a horizontally extensive positive charge layer within the stratiform cloud. In the model, disks with charge densities of 1 and 3 nC m/sup -3/, a thickness of 400 m, and diameters ranging from 20 to 200 km were discharged and produced field changes similar to the observed above-cloud field discontinuities. The authors results support the idea that sprites may be initiated by above-cloud field changes caused by positive cloud-to-ground lightning flashes that discharge a horizontally extensive charge region in the stratiform cloud of a mesoscale convective system. During the time between the electric field discontinuities the electric field above the stratiform clouds was -0.5 to -1.0 kV m/sup -1/; this field may be important in the global electrical circuit because the stratiform clouds have large horizontal extents (À10/sup 4/ km/sup 2/) }, keywords={ atmospheric electricity lightning mesosphere stratosphere thunderstorms atmosphere troposhere stratosphere storm cloud electricity cloud-to-ground lightning mesoscale convective system electric field discontinuity stratiform cloud model sprite mesosphere middle atmosphere thunderstorm 8 to 20 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PoulidaMar96, author={Poulida, O. and Dickerson, R.R. and Heymsfield, A.}, title={ Stratosphere-troposphere exchange in a midlatitude mesoscale convective complex. 1. Observations }, journal={Journal of Geophysical Research}, volume={101}, number={D3}, year={1996}, month={Mar}, pages={6823-36}, abstract={ On June 28, 1989, a severe thunderstorm over North Dakota developed into a squall line and then into a mesoscale convective complex (MCC) with overshooting tops as high as À14 km and a cirrus anvil that covered more than 3*10/sup 5/ km/sup 2/. The authors describe the trace gas concentrations prior to, in, and around the storm. The anvil outflow, sampled at altitudes of 10.8 to 12.2 km, extended well into what used to be the stratosphere. Air inside the anvil was characterized by notably low concentrations of O/sub 3/ and high CO relative to the out-of-cloud environment. Elevated concentrations of NO and NO/sub y/, due to lightning and upward transport, were observed in the anvil. A tongue of air with tropospheric characteristics lay above stratospheric air, showing that extensive stratosphere-troposphere exchange had occurred. The authors estimate a minimum flux of 2*10/sup 10/ g of O/sub 3/ into the troposphere and a maximum flux of 3-7*10/sup 13/ g of H$_2$O into the stratosphere. This is a greater flux of water than the stratospheric water budget can support, and thus most of this water must return to the troposphere; the ice crystals were of sufficient size to have substantial settling velocity. If, however, even a small fraction of the mass of such anvils remains in the stratosphere, then convective transport of reactive tropospheric trace species such as NO/sub y/, CO, and non-methane hydrocarbons may dominate the chemistry of the lower stratosphere in this midlatitude region }, keywords={ atmospheric chemistry stratosphere troposphere stratosphere-troposphere exchange midlatitude mesoscale convective complex observations AD 1989 06 28 North Dakota USA squall line overshooting tops cirrus anvil trace gas concentrations anvil outflow NO/sub y/ lightning upward transport stratospheric water budget ice crystals settling velocity convective transport reactive tropospheric trace species nonmethane hydrocarbons atmospheric chemistry 10.7 to 12.2 km O/sub 3/ H$_2$O CO NO }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Roussel-DupreFeb96, author={Roussel-Dupre, R. and Gurevich, A.V.}, title={ On runaway breakdown and upward propagating discharges }, journal={Journal of Geophysical Research}, volume={101}, number={A2}, year={1996}, month={Feb}, pages={2297-311}, abstract={ The origins of mysterious gamma -ray and radio flashes recently detected by satellite-based instruments passing over thunderstorms are examined in the context of upward propagating discharges initiated by runaway air breakdown. Preliminary calculations normalized by the recent optical measurements of so-called sprites indicate that the runaway mechanism may well be the source of these emissions. If this is true, then upward discharges represent the first known manifestation of a fundamental, new process in plasma physics }, keywords={ atmospheric electricity atmospheric radiation discharges (electric) lightning mesosphere plasma stratosphere thermosphere thunderstorms electric discharge mesosphere electricity middle atmosphere stratosphere thunderstorm sprite runaway breakdown upward propagating discharge gamma -ray emission mysterious gamma -ray flash radio flash runaway air breakdown calculation runaway mechanism upward discharge plasma physics thermosphere upper atmosphere gamma rays }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BrasseurJan96, author={Brasseur, G.P. and Muller, J.-F. and Granier, C.}, title={ Atmospheric impact of NO/sub x/ emissions by subsonic aircraft: a three-dimensional model study }, journal={Journal of Geophysical Research}, volume={101}, number={D1}, year={1996}, month={Jan}, pages={1423-8}, abstract={ Three-dimensional model calculations suggest that the worlds fleet of subsonic aircraft has enhanced the abundance of nitrogen oxides in the upper troposphere by up to 20-35% and has produced a significant increase in the ozone concentration in this region of the atmosphere (4% in summer and 1% in winter). In year 2050, on the basis of current scenarios for growth in aviation, the concentration of NO/sub x/ at 10 km could increase by 30-60% at midlatitudes and the concentration of ozone could be enhanced by 7% and 2% in summer and winter, respectively (relative to a situation without aircraft effects). The perturbation is not limited to the flight corridors but affects the entire northern hemisphere. The magnitude (and even the sign) of the ozone change depends on the level of background atmospheric NO/sub x/ and hence on NO/sub x/ sources (lightning, intrusion from the stratosphere, and convective transport from the polluted boundary layer) and sinks which are poorly quantified in this region of the atmosphere. On the basis of the authors model estimates, 20% of the NO/sub x/ found at 10 km (midlatitudes) is produced by aircraft engines, 25% originates from the surface (combustion and soils), and approximately 50% is produced by lightning. For a lightning source enhanced in the model by a factor of 2, the increase in NO/sub x/ and ozone at 10 km due to aircraft emissions, is reduced by a factor of 2. The magnitude of aircraft perturbations in NO/sub x/ is considerably smaller than the uncertainties in other NO/sub x/ sources }, keywords={ air pollution aircraft atmospheric composition nitrogen compounds ozone troposphere air pollution atmosphere chemical composition aircraft exhaust aircraft emission chemistry troposphere subsonic aircraft three dimensional model calculation ozone AD 1995 to 2050 scenario aviation concentration northern hemisphere lightning NO O/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BaginskiMar96, author={Baginski, M.E. and Hodel, A.S. and Lankford, M.}, title={ An investigation of the reconfiguration of the electric field in the stratosphere following a lightning event }, journal={Journal of Electrostatics}, volume={36}, number={4}, year={1996}, month={Mar}, pages={331-47}, abstract={ Baginski and Hodel (1994) and Baginski and Jarriel (1994) discussed some peculiarities in the late-time electric field and Maxwell current density signatures following a lightning event. In the present paper we extend the analysis to investigate the temporal relationship between the vertical and horizontal electric field in the stratosphere (altitudes 30-50 km) and consider how a quasi-planar region can be defined by introducing the angular orientation ( theta =tan/sup -1/(E/sub z//E/sub y/)) between the respective field components. The geometry, constitutive parameters and assumptions used in the earlier modeling are employed also. Special attention is given to two dimensional graphical representations of the behavior of the electric field that clearly illustrate that a relatively thin segregated region can be defined between a time-varying upper and lower region where the maximum rate of change of the orientation of the field occurs at z/sub p/(t)=h/sub s/log( tau (z)/t). The research reinforces the model presented by Greifinger and Greifinger (1976). An empirical model is also derived from previous research that is in good overall agreement with the simulations }, keywords={ atmospheric electricity current density electric fields lightning stratosphere electric field reconfiguration stratosphere lightning event Maxwell current density temporal relationship vertical electric field horizontal electric field quasi-planar region angular orientation geometry constitutive parameters two dimensional graphical representations thin segregated region time-varying upper region lower region orientation 30 to 50 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HamptonJan96, author={Hampton, D.L. and Heavner, M.J. and Wescott, E.M. and Sentman, D.D.}, title={ Optical spectral characteristics of sprites }, journal={Geophysical Research Letters}, volume={23}, number={1}, year={1996}, month={Jan}, pages={89-92}, abstract={ A TV slit spectrograph was used to obtain the first optical spectra of sprites. Twenty-five events were observed over a thunderstorm on the border of Nebraska and Colorado on the night of 22 June, 1995 between 0700 and 0900 UT. For 10 of these events optical spectra were measured in the wavelength range from 540 to 840 nm. After correcting for the spectrograph response function, digitized spectrograph video images are used to measure the wavelengths of and ratios between the emissions. All emissions are found to be of the first positive bands of N$_2$. There is no evidence of the Meinel bands of N$_2$/sup +/ indicating that the mechanism responsible for sprites produces little or no ionization at 70 km altitude }, keywords={ atmospheric spectra lightning mesosphere stratosphere thunderstorms optical spectral characteristics sprites thunderstorm Nebraska Colorado first positive bands ionization United States AD 1995 06 22 540 to 840 nm N$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @CONFERENCE{Takaki95, author={Takaki, K. and Akiyama, H.}, title={ Characteristics of leader development from a tip of water jet }, booktitle={Ninth International Symposium on High Voltage Engineering}, volume={}, number={}, year={1995}, month={}, pages={6772/1-4 vol.6}, abstract={ A new method to trigger lightning using a water jet instead of a thin wire pulled up by a rocket was proposed and has been investigated. In this paper, characteristics of leader development and flashover between plane electrodes with the water, jetted from behind the grounded electrode through a hole, are described. Applying negative high voltage to the upper electrode, an upward leader discharge develops from a tip of the water jet and the discharge current increases exponentially. The velocities of the leader from tap water are several cm/ mu s, and the velocities increase with the decrease of the water resistivity }, keywords={ electrical conductivity electrodes flashover jets lightning water water jet tip leader development lightning triggering flashover plane electrodes grounded electrode negative high voltage upper electrode upward leader discharge discharge current leader velocities water resistivity }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{RairdenDec95, author={Rairden, R.L. and Mende, S.B.}, title={ Time resolved sprite imagery }, journal={Geophysical Research Letters}, volume={22}, number={24}, year={1995}, month={Dec}, pages={3465-8}, abstract={ Fleeting columns of luminosity occurring above large thunderstorms at 50-90 km altitude, presently known as sprites, were imaged with an intensified video charge coupled device (CCD) camera during a July 1995 ground-based campaign near Fort Collins, Colorado. These unfiltered intensified images reveal detailed spatial structure within the sprite envelope. The temporal resolution of standard interlaced video imagery is limited by the 60 fields per second acquisition rate (16 ms). The specific CCD used, however, is subject to bright events leaking into the readout registers, allowing time-resolution on the order of the linescan rate (63 mu s). Typical sprite onset is found to follow the associated cloud lightning by 1.5 to 4 ms. The onsets of the individual sprites within a cluster are generally, but not always, simultaneous to within 1 ms. Sprites tend to have a bright localized core, less than 2 km in horizontal dimension, which rises to peak intensity within 0.3 ms and maintains this level for 5 to 10 ms before fading over an additional 10 ms }, keywords={ airglow atmospheric radiation lightning mesosphere thermosphere thunderstorms mesosphere upper atmosphere thermosphere optical emission airglow sprite time resolved imagery column luminosity thunderstorm lightning sprites AD 1995 07 Fort Collins Colorado United States USA image spatial structure CCD observations bright localized core intensity 50 to 90 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{InanDec95, author={Inan, U.S. and Bell, T.F. and Pasko, V.P. and Sentman, D.D. and Wescott, E.M. and Lyons, W.A.}, title={ VLF signatures of ionospheric disturbances associated with sprites }, journal={Geophysical Research Letters}, volume={22}, number={24}, year={1995}, month={Dec}, pages={3461-4}, abstract={ VLF perturbations on signals propagating along great-circle-paths (GCP) through electrically active midwest thunderstorms are associated with luminous high altitude glows (referred to as sprites) observed from aircraft or ground. The data constitutes the first evidence that the physical processes leading to sprites also alter the conductivity of the lower ionosphere }, keywords={ airglow ionosphere ionospheric disturbances ionospheric electromagnetic wave propagation lightning mesosphere radiowave propagation thermosphere thunderstorms upper atmosphere ionosphere mesosphere upper atmosphere middle atmosphere VLF signature ionospheric disturbance sprite lightning airglow great-circle-path electrically active midwest thunderstorm United States USA radiowave propagation luminous high altitude glow sprites lower ionosphere electrical conductivity decrease }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{FeldmanDec95, author={Feldman, W.C. and Symbalisty, E.M.D. and Roussel-Dupre, R.A.}, title={ Association of discrete hard X-ray enhancements with eruption of Mount Pinatubo }, journal={Journal of Geophysical Research}, volume={100}, number={A12}, year={1995}, month={Dec}, pages={23829-34}, abstract={ Hard X-ray fluxes in the energy range between 50 keV and 140 keV measured using the Army Background Experiment are found to be associated with the injection by Mount Pinatubo of a massive aerosol into the stratosphere June 14-15, 1991. Discrete X-ray enhancement events are observed to increase from an average of 1.8 per month to 20 during a 1-month interval beginning 12 days after the Mount Pinatubo eruption. Systematics of these enhancements suggests a mechanism that requires a strong coupling between magnetospheric and atmospheric processes, perhaps associated with upward lightning }, keywords={ aerosols atmospheric composition atmospheric electron precipitation atmospheric radiation ionosphere magnetosphere radiation belts stratosphere volcanology magnetosphere ionosphere atmospheric electron precipitation X-ray emission enhancement volcano volcanic eruption Philippines discrete hard X-ray enhancement Mount Pinatubo AD 1991 06 X-ray flux Army Background Experiment massive aerosol stratosphere mechanism strong coupling upward lightning neutral atmosphere magnetosphere interaction 50 to 140 keV }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MendeOct95, author={Mende, S.B. and Rairden, R.L. and Swenson, G.R. and Lyons, W.A.}, title={ Sprite spectra; N$_2$ 1 PG band identification }, journal={Geophysical Research Letters}, volume={22}, number={19}, year={1995}, month={Oct}, pages={2633-6}, abstract={ Imagery and spectra of high altitude luminous flashes, otherwise known as sprites, occurring in the stratosphere/mesosphere above electrically active cumulonimbus clouds were acquired on July 16, 1995 from an observation site near Ft. Collins, Colorado. The spectra, resolved from approximately 4500-8000 AA included four spectral features in the 6000-7600 AA region which have been identified as the N$_2$ 1 PG system with Delta v=2, 3, and 4 from the v=2, 4, 5, 6 vibrational levels of the B/sup 3/ pi /sub g/ state. The spectra were lacking in other features such as the N$_2$/sup +/ Meinel or the N$_2$/sup +/ 1st neg system indicating that the electron energy causing the excitation is quite low }, keywords={ atmospheric spectra nitrogen thunderstorms N$_2$ 1 PG band identification high altitude luminous flashes sprites stratosphere mesosphere electrically active cumulonimbus clouds Ft. Collins Colorado spectra vibrational levels B/sup 3/ pi /sub g/ state electron energy United States AD 1995 07 16 450.0 to 800.0 nm N$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{WincklerJul95, author={Winckler, J.R.}, title={ Further observations of cloud-ionosphere electrical discharges above thunderstorms }, journal={Journal of Geophysical Research}, volume={100}, number={D7}, year={1995}, month={Jul}, pages={14335-45}, abstract={ During the night of 9-10 August 1993 more than 150 luminous cloud-ionosphere discharges (CIs) were observed above a thunderstorm complex moving SE across the state of Iowa. Images of the CIs were obtained through clear air by intensified CCD TV cameras at the O'Brien Observatory of the University of Minnesota located about 60 km NE of Minneapolis and 250-500 km from the storm center. The discharges consisted of bright vertical striations extending from 50-80 km altitude, often covering tens of kilometers laterally, with tendrils of decreasing intensity visible for the brighter events down to cloud tops below 20 km altitude. All the more intense CIs were coincident with a VLF sferic in the 300 Hz-12 kHz range, but small events often did not yield a detectable sferic. There is no unambiguous evidence that CIs were sources of sferics. Some of the CIs were observed to be coincident with a cloud brightening and with a cloud-ground stroke recorded by the National Lightning Detection Network. The duration of the images was generally less than one TV field (<16.7 ms). Many of these discharges have now been observed by the space shuttle, by aircraft-borne TV cameras and a large number by a ground-based camera observations in Colorado. The present results are compared with these observations and recent theoretical ideas related to the CI events are discussed. It is proposed that CIs arise from intense bursts of cloud electrification and may follow the preexisting paths of cloud-to-ionosphere thunderstorm currents }, keywords={ airglow atmospheric electricity lightning mesosphere stratosphere thunderstorms sprite mesosphere electric discharge middle atmosphere cloud-ionosphere electrical discharge thunderstorm thundercloud luminous discharge Iowa optical emission AD 1993 08 09 AD 1993 08 10 bright vertical striation tendrils VLF sferic United States USA atmospherics stratosphere lightning intense burst cloud electrification cloud-to-ionosphere thunderstorm current 20 to 80 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BoccippioAug95, author={Boccippio, D.J. and Williams, E.R. and Heckman, S.J. and Lyons, W.A. and Baker, I.T. and Boldi, R.}, title={ Sprites, ELF transients, and positive ground strokes }, journal={Science}, volume={269}, number={5227}, year={1995}, month={Aug}, pages={1088-91}, abstract={ In two summertime mesoscale convective systems (MCSs), mesospheric optical sprite phenomena were often coincident with both large-amplitude positive cloud-to-ground lightning and transient Schumann resonance excitations of the entire Earth-ionosphere cavity. These observations, together with earlier studies of MCS electrification, suggest that sprites are triggered when the rapid removal of large quantities of positive charge from an areally extensive charge layer stresses the mesosphere to dielectric breakdown }, keywords={ atmospheric electricity atmospherics Earth-ionosphere waveguide lightning mesosphere thunderstorms sprites ELF transients positive ground strokes summertime mesoscale convective systems mesospheric optical sprite phenomena large-amplitude positive cloud-to-ground lightning transient Schumann resonance excitations Earth-ionosphere cavity electrification positive charge removal extensive charge layer stresses mesosphere dielectric breakdown }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{RottgerJul95, author={Rottger, J. and Liu, C.H. and Pan, C.J. and Su, S.Y.}, title={ Characteristics of lightning echoes observed with VHF ST radar }, journal={Radio Science}, volume={30}, number={4}, year={1995}, month={Jul}, pages={1085-97}, abstract={ The development of tropospheric convection was observed with the Chung-Li VHF stratosphere-troposphere (ST) radar in Taiwan. Deep convection evolved into thunderstorms during which radar echoes from lightning were recorded with a particular high time resolution program. These lightning echoes usually exist for only several tens to a few hundred milliseconds. To investigate the fine structure in the amplitude and phase of the lightning returns, the necessary time resolution has to be in the order of a few milliseconds. Such time resolutions are for the first time applied with VHF ST radar and the initial results are presented in the paper. Rapid jumps in the phase path were occurring together with sudden amplitude changes. This indicates that the scattering regions change their position, which could be on different branches of the lightning stroke. Large radial velocities of the lightning scattering regions up to several tens of meters per second were observed. Also, strong velocity shears were noticed in these lightning echo regions. Power peaks in Doppler spectra corresponding to velocities of about 300 m s/sup -1/ were occasionally detected. It is contemplated that these are caused by Bragg scattering from sound waves resulting from the lightning shock wave. Also a periodic velocity and amplitude modulation of a thin sheet of radar reflectivity was observed which one could attribute to infra-sound with a frequency of about 6-7 Hz. Preliminary conclusions are drawn finally to confirm that the observations are generally consistent with backscatter from lightning }, keywords={ atmospheric acoustics Doppler radar lightning meteorological radar remote sensing by radar lightning echoes VHF ST radar tropospheric convection Chung-Li VHF stratosphere-troposphere radar Taiwan thunderstorms radar echoes fine structure amplitude phase lightning returns phase path sudden amplitude change scattering regions radial velocities velocity shears Doppler spectra Bragg scattering sound waves periodic velocity amplitude modulation radar reflectivity }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanJun95, author={Sentman, D.D. and Wescott, E.M.}, title={ Red sprites and blue jets: thunderstorm-excited optical emissions in the stratosphere, mesosphere, and ionosphere }, journal={Phys. Plasmas (USA), Physics of Plasmas}, volume={2}, number={6}, year={1995}, month={Jun}, pages={2514-22}, abstract={ Low light level monochrome television observations obtained from the ground and from the space Shuttle, and low light level color and monochrome television images obtained from aboard jet aircraft, have shown that intense lightning in mesoscale thunderstorm systems may excite at least two distinct types of optical emissions that together span the space between the tops of some thunderstorms and the ionosphere. The first of these emissions, dubbed "sprites," are luminous red structures that typically span the altitude range 60-90 km, often with faint bluish tendrils dangling below. A second, rarer, type of luminous emission are "blue jets" that appear to spurt upward out of the anvil top in narrow cones to altitudes of 40-50 km at speeds of approximately 100 km/s. In the paper the principal observational characteristics of sprites and jets are presented, and several proposed production mechanisms are reviewed }, keywords={ atmospheric radiation ionospheric disturbances mesosphere stratosphere thunderstorms thunderstorm-excited optical emissions stratosphere mesosphere ionosphere red sprites blue jets low light level monochrome television observations mesoscale thunderstorm systems tendrils luminous emission anvil top narrow cones production mechanisms review }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanMay95, author={Sentman, D.D. and Wescott, E.M. and Osborne, D.L. and Hampton, D.L. and Heavner, M.J.}, title={ Preliminary results from the Sprites94 aircraft campaign. 1. Red sprites }, journal={Geophysical Research Letters}, volume={22}, number={10}, year={1995}, month={May}, pages={1205-8}, abstract={ The dual jet aircraft Sprites94 campaign yielded the first color imagery and unambiguously triangulated physical dimensions and heights of upper atmospheric optical emissions associated with thunderstorm systems. Low light level television images, in both color and in black and white, obtained during the campaign show that there are at least two distinctively different types of optical emissions spanning part or all of the distance between the anvil tops and the ionosphere. The first of these emissions, dubbed "sprites" after their elusive nature, are luminous structures of brief (<16 ms) duration with a red main body that typically spans the altitude range 50-90 km, and possessing lateral dimensions of 5-30 km. Faint bluish tendrils often extend downward from the main body of sprites, occasionally appearing to reach cloud tops near 20 km. The principal characteristics of red sprites as observed during the Sprites94 campaign are described }, keywords={ atmospheric radiation atmospheric spectra ionosphere thunderstorms Sprites94 aircraft campaign red sprites dual jet aircraft observations colour imagery triangulated physical dimensions heights upper atmospheric optical emissions thunderstorm systems low light level television images anvil tops ionosphere luminous structures altitude range lateral dimensions faint bluish tendrils AD 1994 06 to 07 50 to 90 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PaskoFeb95, author={Pasko, V.P. and Inan, U.S. and Taranenko, Y.N. and Bell, T.F.}, title={ Heating, ionization and upward discharges in the mesosphere due to intense quasi-electrostatic thundercloud fields }, journal={Geophysical Research Letters}, volume={22}, number={4}, year={1995}, month={Feb}, pages={365-8}, abstract={ Quasi-electrostatic fields that temporarily exist at high altitudes following the sudden removal (e.g. by a lightning discharge) of thundercloud charge at low altitudes are found to significantly heat mesospheric electrons and produce ionization and light. The intensity, spatial extent, duration and spectra of optical emissions produced are consistent with the observed features of the red sprite type of upward discharges }, keywords={ atmospheric ionisation electrons electrostatic discharge mesosphere plasma heating thunderstorms mesospheric electron heating ionization upward discharges mesosphere intense quasielectrostatic thundercloud fields lightning discharge sudden thundercloud charge removal light production ionization production intensity spatial extent duration spectra optical emissions red sprites }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MilikhJan95, author={Milikh, G.M. and Papadopoulos, K. and Chang, C.L.}, title={ On the physics of high altitude lightning }, journal={Geophysical Research Letters}, volume={22}, number={2}, year={1995}, month={Jan}, pages={85-8}, abstract={ Past and recent observations indicate the presence of lightning at altitudes in excess of 30 km. The phenomenon is manifested as a high altitude optical flash, correlated with the presence of giant thunderstorms in the atmosphere below. This letter presents the first physical model of the process. The model is based on low frequency RF breakdown of the upper atmosphere, ignited by the upward propagating electromagnetic pulses due to conventional low altitude lightning. Horizontal intercloud lightning strokes form the optimal configuration. Horizontal lightning discharges with cloud-to-cloud moment charge approximately 6000-8000 C-km account for the observed level of optimal emissions }, keywords={ lightning mesosphere stratosphere electric breakdown stratosphere middle atmosphere mesosphere high altitude lightning optical flash giant thunderstorms physical model frequency RF breakdown upper atmosphere 30 to 80 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{WangApr95, author={Wang, D. and Ushio, T. and Kawasaki, Z.-I. and Matsuura, K. and Shimada, Y. and Uchida, S. and Yamanaka, C. and Izawa, Y. and Sonoi, Y. and Simokura, N.}, title={ A possible way to trigger lightning using a laser }, journal={J. Atmos. Terr. Phys. (UK), Journal of Atmospheric and Terrestrial Physics}, volume={57}, number={5}, year={1995}, month={Apr}, pages={459-66}, abstract={ To study the possibility of triggering lightning with a laser plasma, laboratory laser-induced discharge experiments have been carried out and the following results were obtained. Both long straight and zigzag laser-induced discharges between rod-rod electrodes were realized and the effective guiding effect of laser channels for electrical discharges was confirmed. With plane-plane electrode configuration, the investigation concerning the necessary condition for initiating and guiding a streamer reveals that the necessary electric field for initiating a streamer with a laser plasma depends closely on the absorbed energy used to produce the laser plasma channels, the minimum electric field is about 200 kV/m, and that the necessary electric field for guiding a streamer by a laser plasma is lower than that for initiating a streamer and the minimum electric field is about 170 kV/m. The authors propose to use the local electric field near the top of a grounded tower as the necessary field for a laser-produced channel to trigger an upward leader and have proved that this is feasible }, keywords={ lightning plasma production by laser lightning triggering laser plasma laboratory laser-induced discharge experiments rod-rod electrodes laser channels electrical discharges plane-plane electrode configuration streamer electric field absorbed energy minimum electric field grounded tower upward leader }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BoeckJan95, author={Boeck, W.L. and Vaughan, O.H., Jr. and Blakeslee, R.J. and Vonnegut, B. and Brook, M. and McKune, J.}, title={ Observations of lightning in the stratosphere }, journal={Journal of Geophysical Research}, volume={100}, number={D1}, year={1995}, month={Jan}, pages={1465-75}, abstract={ An examination and analysis of video images of lightning, captured by the payload bay TV cameras of the Space Shuttle, provided a variety of examples of lightning in the stratosphere above thunderstorms. These images were obtained on several Shuttle flights while conducting the Mesoscale Lightning Experiment (MLE). The images of stratospheric lightning illustrate the variety of filamentary and broad vertical discharges in the stratosphere that may accompany a lightning flash. A typical event is imaged as a single or multiple filament extending 30 to 40 km above a thunderstorm that is illuminated by a series of lightning strokes. Examples are found in temperate and tropical areas, over the oceans, and over the land }, keywords={ lightning stratosphere thunderstorms lightning stratosphere video images thunderstorms filamentary vertical discharges broad vertical discharges 30 to 40 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HaleOct94, author={Hale, L.C.}, title={ Coupling of ELF/ULF energy from lightning and MeV particles to the middle atmosphere, ionosphere, and global circuit }, journal={J. Geophys. Res. (USA), Journal of Geophysical Research}, volume={99}, number={D10}, year={1994}, month={Oct}, pages={21089-96}, abstract={ In an attempt to explain numerous atmospheric electrical phenomena, the elements of the global electrical circuit are reexamined. In addition to being a "quasi-static "DC" generator" and source of radiated energy at VLF and higher, the thunderstorm is found to be a pulse generator, with most of the external energy contained in ELF and ULF pulse currents to the ionosphere (and Earth). The pulse energy is found to deposit largely in the middle atmosphere above the thunderstorm. The VLF and above components are well understood, as are the ULF components due to the conductivity gradient. However, a previously poorly understood ELF component on the millisecond timescale, or "slow tail," contains a large fraction of the electrical energy. This component couples strongly to the ionosphere and also launches a unipolar transverse EM wavelet in the radial Earth-ionosphere transmission line. The increase in charge with distance associated with such wavelets, and their ensemble sum at a point, may explain some large mesospheric "DC" fields. These millisecond duration unipolar wavelets also couple to the ionosphere and may trigger other lightning at a distance. A schema is elucidated by which the charge of MeV particles deposited in the middle atmosphere persists for much longer than the local relaxation time. This also gives rise to unipolar waves of global extent which may explain lower-latitude field perturbations associated with solar/geomagnetic events }, keywords={ atmospheric electricity Earth-ionosphere waveguide ionosphere lightning ELF/ULF energy coupling lightning MeV particles middle atmosphere ionosphere global electrical circuit atmospheric electrical phenomena quasistatic DC generator VLF radiated energy source thunderstorm pulse generator conductivity gradient slow tail electrical energy unipolar transverse EM wavelet radial Earth-ionosphere transmission line mesospheric DC fields unipolar waves }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{CoorayOct94, author={Cooray, V. and Jayaratne, K.P.S.C.}, title={ Characteristics of lightning flashes observed in Sri Lanka in the tropics }, journal={J. Geophys. Res. (USA), Journal of Geophysical Research}, volume={99}, number={D10}, year={1994}, month={Oct}, pages={21051-6}, abstract={ Characteristics of lightning ground flashes in Sri Lanka, in the tropics, were measured by recording the electric field generated by the whole flash at microsecond resolution. The geometric and arithmetic means of the interstroke intervals were 57 ms and 83 ms, respectively. It was found that about 35% of the multiple stroke, negative ground flashes had at least one subsequent stroke with a peak electric field larger than that of the first return stroke. Furthermore, about 12% of the subsequent strokes had peak electric field amplitudes larger than those of the first return strokes. The geometric mean of the subsequent stroke peak field to the first return stroke peak field ratio was 0.44. The mean number of strokes per flash was 4.5, and 21% of the flashes were single-stroke flashes. A comparison of the results with those observed in Florida and in Sweden shows that there are remarkable similarities in the characteristics of lightning ground flashes observed in different geographical regions }, keywords={ lightning lightning ground flashes Sri Lanka tropics electric field microsecond resolution recordings interstroke intervals multiple strokes negative ground flashes peak electric field amplitude Colombo AD 1993 04 }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LyonsMay94, author={Lyons, W.A.}, title={ Characteristics of luminous structures in the stratosphere above thunderstorms as imaged by low-light video }, journal={Geophysical Research Letters}, volume={21}, number={10}, year={1994}, month={May}, pages={875-8}, abstract={ An experiment was conducted in which an image-intensified low-light video camera systematically monitored the stratosphere above distant (100-800 km) mesoscale convective systems over the high plains of the central U.S. for 21 nights between 6 July and 27 August 1993. Complex, luminous structures were observed above large thunderstorm clusters on eleven nights, with one storm system (7 July 1993) yielding 248 events in 410 minutes. Their duration ranged from 33 to 283 ms, with an average of 98 ms. The luminous structures, generally not visible to the naked, dark-adapted eye, exhibited on video a wide variety of brightness levels and shapes including streaks, aurora-like curtains, smudges, fountains and jets. The structures were often more than 10 km wide and their upper portions extended to above 50 km msl }, keywords={ atmospheric radiation stratosphere thunderstorms complex luminous structures stratosphere thunderstorms cloud-to-space events image-intensified low-light video camera mesoscale convective systems central USA AD 1993 07 06 to 08 27 cloud-to-stratosphere events thunderstorm clusters storm system brightness levels shapes streaks curtains smudges fountains jets cloud-to-ionosphere events 50 km 400 to 900 nm }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Daohong-WangAug94, author={Daohong Wang and Kawasaki, Z.-I. and Matsuura, K. and Shimada, Y. and Uchida, S. and Yamanaka, C. and Fujiwara, E. and Izawa, Y. and Simokura, N. and Sonoi, Y.}, title={ A preliminary study on laser-triggered lightning }, journal={Journal of Geophysical Research}, volume={99}, number={D8}, year={1994}, month={Aug}, pages={16907-12}, abstract={ As a preliminary study on triggering lightning with a CO$_2$ high-power laser, the authors carried out laser-triggered discharge experiments to investigate the necessary conditions for initiating and guiding an electrical streamer with a CO$_2$ laser-produced plasma channel. They found the following: (1) the necessary electric field for initiating a streamer with the plasma channel depends closely on the absorbed energy for producing the plasma channel and not on the length of the plasma channel. The higher the absorbed energy, the smaller the necessary electric field. The minimum electric field is about 200 kV/m. (2) The necessary electric field for guiding a streamer by the plasma channel is lower than that for initiating a streamer. The minimum electric field is about 170 kV/m. Furthermore, the authors observed the electric field at the top of a 50-m tower and the field on the ground simultaneously during 10 Japanese winter thunder-storms. The observed results agree with theoretical calculations showing that the field at the top of a 50-m tower is on average 2 orders larger than the field on the ground. They conclude that it is highly possible to trigger a lightning discharge if one shoots a CO$_2$ laser-produced plasma channel upward through the top of a high grounded tower under conditions of high thunderstorm electric fields }, keywords={ carbon compounds gas lasers lightning plasma plasma production and heating by laser beam thunderstorms laser-triggered lightning CO$_2$ high-power laser laser-triggered discharge experiments electrical streamer electric field plasma channel Japan winter thunderstorms CO$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LelieveldJun94, author={Lelieveld, J. and Crutzen, P.J.}, title={ Role of deep cloud convection in the ozone budget of the troposphere }, journal={Science}, volume={264}, number={5166}, year={1994}, month={Jun}, pages={1759-61}, abstract={ Convective updrafts in thunderstorms prolong the lifetime of ozone (O/sub 3/) and its anthropogenic precursor NO/sub x/ (nitric oxide (NO)+nitrogen dioxide (NO$_2$)) by carrying these gases rapidly upward from the boundary layer into a regime where the O/sub 3/ production efficiency is higher, chemical destruction is slower, and surface deposition is absent. On the other hand, the upper troposphere is relatively rich in O/sub 3/ and NO/sub x/ from natural sources such as downward transport from the stratosphere and lightning; convective overturning conveys the O/sub 3/ and NO/sub x/ toward the Earth's surface where these components are more efficiently removed from the atmosphere. Simulations with a three-dimensional global model suggest that the net result of these counteractive processes is a 20 percent overall reduction in total tropospheric O/sub 3/. However, the net atmospheric oxidation efficiency is enhanced by 10 to 20 percent }, keywords={ air pollution atmospheric composition atmospheric movements clouds ozone thunderstorms troposphere deep cloud convection troposphere convective updrafts thunderstorms NO/sub x/ boundary layer O/sub 3/ production efficiency chemical destruction surface deposition downward transport stratosphere lightning convective overturning three-dimensional global model oxidation efficiency O/sub 3/ NO NO$_2$ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BaginskiJun94, author={Baginski, M.E. and Jarriel, G.W., Jr.}, title={ Characterization of thunderstorm induced Maxwell current densities in the middle atmosphere }, journal={Journal of Electrostatics}, volume={33}, number={1}, year={1994}, month={Jun}, pages={87-102}, abstract={ Middle atmospheric transient Maxwell current densities generated by lightning induced charge perturbations are investigated via a simulation of Maxwell's equations. A time domain finite element analysis is employed for the simulations. The atmosphere is modeled as a region contained within a right circular cylinder with a height of 110 km and a radius of 80 km. A composite conductivity profile based on measured data is used with charge perturbations centered about the vertical axis at altitudes of 6 and 10 km. The simulations indicate that the temporal structure of the Maxwell current density is relatively insensitive to altitude variations within the region considered. It is also shown that the electric field and Maxwell current density are not generally aligned }, keywords={ electromagnetic induction lightning Maxwell equations mesosphere thunderstorms thunderstorm induced Maxwell current densities induced Maxwell current densities transient Maxwell current densities middle atmosphere lightning induced charge perturbations simulation Maxwell's equations time domain finite element analysis right circular cylinder height radius composite conductivity profile measured data charge perturbations vertical axis altitudes temporal structure electric field 80 km 6 km 10 km 110 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{DowdenSep94, author={Dowden, R.L. and Adams, C.D.D. and Brundell, J.B. and Dowden, P.E.}, title={ Rapid onset, rapid decay (RORD), phase and amplitude perturbations of VLF subionospheric transmissions }, journal={Journal of Atmospheric and Terrestrial Physics}, volume={56}, number={11}, year={1994}, month={Sep}, pages={1513-27}, abstract={ Rapid onset (few ms), rapid decay ( approximately 1 s) perturbations or RORDs occur frequently on the west-to-east signal from NWC to Dunedin, more often than not with classic Trimpis. They do not appear on an NWC mimic signal directly injected into the antenna and so cannot be broadband bursts. There is no delay between the initiating sferic and RORD start, implying that they are produced not by whistler-induced electron precipitation but directly by lightning. Observations on a multi-element array show that classic Trimpis and RORDs initiated by the same sferic usually come from measurably different directions, so the lightning-induced ionisation enhancements which cause them must be laterally displaced. They may also be vertically displaced to explain the differing decay rates (30 s versus 1 s). The authors conclude that RORDs are VLF echoes from vertical columns of ionisation at around 40 km altitude and having vertical dimensions of some tens of km and horizontal dimensions of 1-2 km, since such a column would scatter sufficient signal to fit observed amplitudes. Cloud-to-ionosphere lightning discharges (also called >>OPEN"/cloud-to-space" and "cloud-to-stratosphere" discharges) of these visible dimensions have been observed on mountain observatories and on board the Space Shuttle }, keywords={ ionospheric electromagnetic wave propagation radiowave propagation rapid onset rapid decay perturbations RORD phase perturbations amplitude perturbations VLF subionospheric transmissions Trimpis initiating sferic multielement array obseravtions laterally displaced lightning-induced ionisation enhancements decay rates VLF echoes vertical ionisation columns cloud-to-ionosphere lightning discharges cloud-to-space discharges cloud-to-stratosphere discharges }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{DriscollMay94, author={Driscoll, K.T. and Blakeslee, R.J. and Koshak, W.J.}, title={ Time-averaged current analysis of a thunderstorm using ground-based measurements }, journal={J. Geophys. Res. (USA), Journal of Geophysical Research}, volume={99}, number={D5}, year={1994}, month={May}, pages={10653-61}, abstract={ The amount of upward current provided to the ionosphere by a thunderstorm that appeared over the Kennedy Space Center on 11 July 1978, is reexamined using an analytic equation that describes a bipolar thunderstorm's current contribution to the global circuit in terms of its generator current, lightning currents, the altitudes of its charge centers, and the conductivity profile of the atmosphere. Ground-based measurements, which were obtained from a network of electric field mills positioned at various distances from the thunderstorm, were used to characterize the electrical activity inside the thundercloud. The location of the lightning discharges, the type of lightning, and the amount of charge neutralized during this thunderstorm were computed through a least squares inversion of the measured changes in the electric fields following each lightning discharge. These measurements provided the information necessary to implement the analytic equation, and consequently, a time-averaged estimate of this thunderstorm's current contribution to the global circuit was calculated. From these results the amount of conduction current supplied to the ionosphere by this small thunderstorm was computed to be less than 25% of the time-averaged generator current that flowed between the two vertically displaced charge centers }, keywords={ ionosphere lightning ionosphere atmosphere AD 1978 07 11 USA Florida electric current time-averaged current analysis global circuit storm upward current Kennedy Space Center analytic equation bipolar thunderstorm generator current lightning electric field }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{FishmanMay94, author={Fishman, G.J. and Bhat, P.N. and Mallozzi, R. and Horack, J.M. and Koshut, T. and Kouveliotou, C. and Pendleton, G.N. and Meegan, C.A. and Wilson, R.B. and Paciesas, W.S. and Goodman, S.J. and Christian, H.J.}, title={ Discovery of intense gamma-ray flashes of atmospheric origin }, journal={Science}, volume={264}, number={5163}, year={1994}, month={May}, pages={1313-16}, abstract={ Detectors aboard the Compton Gamma Ray Observatory have observed an unexplained terrestrial phenomenon: brief, intense flashes of gamma rays. These flashes must originate in the atmosphere at altitudes above at least 30 kilometers in order to escape atmospheric absorption and reach the orbiting detectors. At least a dozen such events have been detected over the past 2 years. The photon spectra from the events are very hard (peaking in the high-energy portion of the spectrum) and are consistent with bremsstrahlung emission from energetic (million-electron volt) electrons. The most likely origin of these high-energy electrons, although speculative at this time, is a rare type of high-altitude electrical discharge above thunderstorm regions }, keywords={ atmospheric electricity atmospheric radiation bremsstrahlung ionosphere mesosphere thunderstorms intense gamma-ray flashes Compton Gamma Ray Observatory photon spectra bremsstrahlung emission energetic electrons high-altitude electrical discharge thunderstorm regions 30 to 80 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanDec93, author={Sentman, D.D. and Wescott, E.M.}, title={ Observations of upper atmospheric optical flashes recorded from an aircraft }, journal={Geophysical Research Letters}, volume={20}, number={24}, year={1993}, month={Dec}, pages={2857-60}, abstract={ Short-duration upper atmospheric optical flashes were recorded on the night of 8 July, 1993 (9 July UT) from the NASA DC-8 Airborne Laboratory flying over the American Midwest. All-sky video images from an intensified silicon intensified target (ISIT) camera revealed 19 upper atmospheric flashes occurring over a period of approximately 100 min. The flashes were similar in appearance to previously reported ground and shuttle-based video observations. Detailed analysis of 12 of the events yielded these parameters: duration 1000 km/sup 3/. The relative frequency of the optical flashes was 1:200-1:400 compared to negative cloud-to-ground discharges and 1:20-1:40 compared to positive cloud-to-ground discharges }, keywords={ atmospheric electricity atmospheric radiation thunderstorms upper atmosphere upper atmosphere electrical discharges stratosphere mesosphere lower thermosphere flash brightness thunderstorms AD 1993 07 08 to 09 Kansas Iowa central United States Nebraska USA aeronomy flash duration all-sky video images upper atmospheric optical flashes 8 July, 1993 terminal heights horizontal extent emission volume relative frequency optical flashes negative cloud-to-ground discharges positive cloud-to-ground discharges 0 to 17 ms 30 to 100 km 10 to 50 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{KotamarthiApr94, author={Kotamarthi, V.R. and Ko, M.K.W. and Weisenstein, D.K. and Rodriguez, J.M. and Sze, N.D.}, title={ Effect of lightning on the concentration of odd nitrogen species in the lower stratosphere: an update }, journal={Journal of Geophysical Research}, volume={99}, number={D4}, year={1994}, month={Apr}, pages={8167-73}, abstract={ Revised model estimates of the effect of lightning on the lower stratospheric NO/sub y/ are presented. Several changes in the Atmospheric and Environmental Research Incorporated model were made since the last evaluation of the impact of lightning. Improvements were made in the model circulation and location of tropopause in the tropics, which is now calculated from the National Meteorological Center temperature data. Changes in model circulation reduced the mass flux from the troposphere to the tropical stratosphere. The calculated mass fluxes are found to agree better with recent estimates. The circulation changes also reduced the advective mass flux from the tropical lower stratosphere to the midlatitudes. The change in circulation and the change in the tropopause height lead to increases in the calculated concentration of N$_2$O, O/sub 3/ and NO/sub y/ in the tropical lower stratosphere. The effect of lightning is to increase the calculated concentration of NO/sub y/ around 64 mbar by a factor of 2, compared to a factor of 10 enhancement in the previous calculations. Comparison with the Stratosphere Troposphere Exchange Project 1987 data indicates that the inclusion of a lightning source brings the model results in closer agreement with the observations }, keywords={ atmospheric composition hydrogen compounds lightning nitrogen compounds stratosphere odd N species lower stratosphere lightning NO/sub y/ circulation tropopause tropics mass flux troposphere midlatitudes concentration N$_2$O O/sub 3/ NO N NO$_2$ NO/sub 3/ HNO$_2$ HNO/sub 3/ N$_2$O/sub 5/ ClNO/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanFeb94, author={Sentman, D.D. and Ehring, D.A.}, title={ Midlatitude detection of ELF whistlers }, journal={Journal of Geophysical Research}, volume={99}, number={A2}, year={1994}, month={Feb}, pages={2183-90}, abstract={ Narrow-band, whistlerlike magnetic events distinguished by nearly monochromatic signals decreasing in frequency with time have been observed for the first time at midlatitudes in the ELF band. Measurements performed during 1985 September 3 to October 5 at Table Mountain, California (34.4 degrees N, 117.7 degrees W), show that the frequency and dispersion characteristics of these events are similar to events detected at auroral latitudes (Heacock, 1974), including a narrow-band magnetic signal monotonically decreasing in frequency from 120 to 60 Hz over a 40 s interval with a mean center frequency of approximately 90 Hz. Following Heacock (1974), it is suggested that a possible source for these events is whistler mode lion roars occurring in field-aligned ducts of enhanced cold plasma densities in the distant magnetosheath }, keywords={ magnetospheric electromagnetic wave propagation whistlers ELF whistlers midlatitude detection narrow-band whistler-like magnetic events AD 1985 09 03 to 10 05 frequency characteristics dispersion characteristics narrow-band magnetic signal whistler mode lion roars field-aligned ducts cold plasma densities magnetosheath whistler-like magnetic pulsations 60 to 180 Hz }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{RycroftMar94, author={Rycroft, M.J.}, title={ Some effects in the middle atmosphere due to lightning }, journal={J. Atmos. Terr. Phys. (UK), Journal of Atmospheric and Terrestrial Physics}, volume={56}, number={3}, year={1994}, month={Mar}, pages={343-8}, abstract={ A brief review is given of some of the electrodynamic responses of the middle atmosphere to lightning. Attention is focused on the precipitation of energetic electrons from the magnetosphere due to whistler mode electromagnetic waves. The secondary ionisation and bremsstrahlung radiation created, and some of the ways in which such effects can be detected, are also considered. Finally, the possibilities of positive feedback mechanisms operating between the atmosphere and the magnetosphere are investigated }, keywords={ atmospheric electron precipitation ionosphere lightning magnetosphere mesosphere mesosphere ionosphere energetic electron precipitation wave particle interaction middle atmosphere lightning electrodynamic responses magnetosphere whistler mode electromagnetic waves secondary ionisation bremsstrahlung radiation positive feedback mechanisms }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Mar94, author={}, title={ Electrodynamics of the Middle Atmosphere. Joint IAGA/IAMAP Symposium }, journal={Journal of Atmospheric and Terrestrial Physics}, volume={56}, number={3}, year={1994}, month={Mar}, pages={}, abstract={ The following topics were dealt with: middle atmosphere electric fields, electric field generation by aerosol particle flow, lightning induced effects, multipole thundercloud electric fields penetration into ionosphere }, keywords={ atmospheric composition atmospheric electricity atmospheric ionisation ionosphere mesosphere stratosphere upper atmosphere mesosphere stratosphere upper atmosphere middle atmosphere electric field generation aerosol particle flow lightning multipole thundercloud electric fields penetration ionosphere 10 to 100 km }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PintoNov92, author={Pinto, I.R.C.A. and Pinto, O., Jr. and Gin, R.B.B. and Diniz, J.H. and de Araujo, R.L. and Carvalho, A.M.}, title={ A coordinated study of a storm system over the South American continent. 2. Lightning-related data }, journal={Journal of Geophysical Research}, volume={97}, number={D16}, year={1992}, month={Nov}, pages={18205-13}, abstract={ For pt.1 see ibid., vol.97, no.D16, p.18195-204 (1992). On December 13, 1989, a coordinated campaign was conducted in Brazil to study the electrical signatures associated with a large storm system over the South American continent. Balloon-borne VLF electric field data showed more than a hundred lightning-related stratospheric vertical electric field (sferics) signatures during approximately 6 hours. The sferic signatures were characterized by a rapid transient with peak amplitudes exceeding 7 V/m which would be expected by the removal of positive charge below followed by a slow recovery. This signature indicates that the lightning strokes experienced by the balloon were either cloud discharges or positive ground discharges. The peak amplitudes indicate that the positively charged region is of the order of tens of coulombs. The recovery curves are quite variable, reflecting the complex nature of the propagating phenomena in the atmosphere }, keywords={ atmospherics lightning stratosphere South America atmosphere lightning atmospherics AD 1989 12 13 stratosphere sferics radiowave emission storm system Brazil electrical signatures VLF electric field stratospheric vertical electric field sferic rapid transient positively charged region }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{PintoNov92, author={Pinto, O., Jr. and Pinto, I.R.C.A. and Gin, R.B.B. and Mendes, O., Jr.}, title={ A coordinated study of a storm system over the South American continent. 1. Weather information and quasi-DC stratospheric electric field data }, journal={Journal of Geophysical Research}, volume={97}, number={D16}, year={1992}, month={Nov}, pages={18195-204}, abstract={ Reports on a coordinated campaign conducted in Brazil on 13 December 1989 to study the electrical signatures associated with a large storm system over the South American continent. Inside the storm, large convective cells developed extending up to the tropopause, as revealed from meteorological balloon soundings. Quasi-DC vertical electric field and temperature were measured by zero-pressure balloon-borne payload launched from Cachoeira Paulista, Brazil. The data were supported by radar and GOES satellite observations, as well as by a lightning position and tracking system. The analysis of infrared imagery supports the general tendency for lightning strikes to be near to but not exactly under the coldest cloud tops. In turn, the radar maps located the strikes near to but outside of the most intense areas of precipitation. The quasi-DC vertical electric field remained during most of the flight in a reversed direction relative to the usual fair weather downward orientation with values as large as 4 V/m }, keywords={ atmospheric electricity lightning storms stratosphere atmosphere meteorology South America stratosphere DC field AD 1989 12 13 storm system electric Brazil large convective cells temperature Paulista lightning reversed direction }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{VaughanJul92, author={Vaughan, O.H., Jr. and Blakeslee, R. and Boeck, W.L. and Vonnegut, B. and Brook, M. and McKune, J., Jr.}, title={ A cloud-to-space lightning as recorded by the Space Shuttle payload-bay TV cameras }, journal={Monthly Weather Review}, volume={120}, number={7}, year={1992}, month={Jul}, pages={1459-61}, abstract={ Video images from space showing a single upward luminous discharge into the clear night air above a thunderstorm were recorded for the first time during the Space Shuttle STS-32 mission, and later during the STS-31 mission and other missions using the Shuttle's payload-bay TV cameras. The upward luminous discharge was seen to move out of the top of a single thunderstorm during the flight of STS-31. This video image was taken at 0335:59 UTC 28 April 1990 while the shuttle was passing over Mauritania, northwest Africa. The storm that had the luminous discharge was located at approximately 7.5 degrees N, 4.0 degrees E, and was about 2000 km from the shuttle's position. The lightning discharge was determined to be at least 31 km long. This discharge is of interest because it is probably caused by an electric-field concentration in the upper part of the thunderstorm and appears to be a discharge that was predicted by Wilson (1925) }, keywords={ lightning thunderstorms upward discharge atmosphere AD 1990 Mauritania Africa cloud-to-space lightning Space Shuttle single upward luminous discharge night thunderstorm STS-32 STS-31 }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BityurinNov91, author={Bityurin, V.A. and Bocharov, A.N.}, title={ Hall breakdown in an MHD generator channel }, journal={Teplofizika Vysokikh Temperatur}, volume={29}, number={6}, year={1991}, month={Nov}, pages={1224-33}, abstract={ A numerical investigation shows the possibility of an electrothermal interelectrode breakdown of the wall of an MHD-channel. Two-dimensional calculations were done for conditions close to those in large-scale MHD channels: Reynolds number approximately=5.10/sup 6/, magnetic field 2.5 and 5 T, and average electron current density 0-5 A/cm/sup 2/. Examination of the charge at the anode wall, which consists of ceramic electrodes and insulators, shows that the most probable breakdown from an induced electric field occurs in the insulating gap from a continuous upward propagation of an overheated region of the insulator through the flow. Integral electrical characteristics of the discharge are presented for two values of the magnetic field and various electrical loads on the part of the wall under investigation, and the two-dimensional distributions of the potential, current, and temperature are displayed }, keywords={ electric breakdown of solids magnetohydrodynamic convertors two-dimensional calculations Hall breakdown integral electrical characteristics MHD generator channel electrothermal interelectrode breakdown wall Reynolds number magnetic field electron current density anode wall ceramic electrodes insulators induced electric field insulating gap overheated region electrical loads two-dimensional distributions }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 /usr/tmp/citation.tmp.27694 @ARTICLE{FarrellApr92, author={Farrell, W.M. and Desch, M.D.}, title={ Cloud-to-stratosphere lightning discharges: a radio emission model }, journal={Geophysical Research Letters}, volume={19}, number={7}, year={1992}, month={Apr}, pages={665-8}, abstract={ Observations of rare cloud-to-stratospheric lightning discharges suggest the events are inherently 'slow-rising', with the emitted energy reaching peak values in about 10 milliseconds. Applying a dipole radiation model, the authors demonstrate that the emitted radio wave energy from such slow-rising events is strongest below about 50 Hz, and possesses a significant rolloff at higher frequencies. In the analysis, various current distributions are considered in order to determine the effect on the radio spectrum. Near 10 kHz, the emission from cloud-to-stratospheric lightning is significantly reduced as compared to the typical cloud-to-ground return stroke, with amplitudes as much as 50 dB lower. This result may explain the lack of detection of VLF signals from recently observed long-lasting discharge events }, keywords={ atmospheric radiation atmospherics lightning stratosphere radio emission model cloud-to-stratospheric lightning discharges dipole radiation model emitted radio wave energy slow-rising events current distributions }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{EhhaltMar92, author={Ehhalt, D.H. and Rohrer, F. and Wahner, A.}, title={ Sources and distribution of NO/sub x/ in the upper troposphere at northern mid-latitudes }, journal={Journal of Geophysical Research}, volume={97}, number={D4}, year={1992}, month={Mar}, pages={3725-38}, abstract={ A simple quasi-two-dimensional model is used to study the zonal distribution of NO/sub x/. The model includes vertical transport in the form of eddy diffusion and deep convection, zonal transport by a vertically uniform wind, and a simplified chemistry of NO, NO$_2$, and HNO/sub 3/. The NO/sub x/ sources considered are surface emissions (mostly from the combustion of fossil fuel), lightning, aircraft emissions, and downward transport from the stratosphere. The model is applied to the latitude band of 40 degrees to 50 degrees N during the month of June; the contributions to the zonal NO/sub x/ distribution from the individual sources and transport processes are investigated. The model predicted NO/sub x/ concentration in the upper troposphere is dominated by air lofted from the polluted planetary boundary layer over the large industrial areas of eastern North America and Europe. Aircraft emissions are also important and contribute on average 30%. Stratospheric input is minor about 10%, less even than that by lightning }, keywords={ air pollution atmospheric composition nitrogen compounds troposphere source atmosphere chemical composition middle latitude midlatitude air pollution upper troposphere quasi-two-dimensional model zonal distribution vertical transport eddy diffusion deep convection lightning NO/sub x/ NO NO$_2$ HNO/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MiromotoOct91, author={Miromoto, A. and Matsumoto, M. and Yoshita, M. and Kumeda, M. and Shimizu, T.}, title={ Doping effect of oxygen or nitrogen impurity in hydrogenated amorphous silicon films }, journal={Applied Physics Letters}, volume={59}, number={17}, year={1991}, month={Oct}, pages={2130-2}, abstract={ O, N, or C impurity was separately incorporated into a-Si:H films by hot-wall glow discharge decomposition. The effect of the impurity incorporation was investigated by electrical and electron spin resonance measurements. Both O and N impurities were found to increase the dark conductivity by decreasing its activation energy in a-Si:H films. Furthermore, it was found that O and N impurities delay the photoresponse. C impurity, however, has no appreciable effect on them. These findings suggest that O and N impurities shift the Fermi level upward and form a trapping state for photoexcited electrons, supporting the authors O/sub 3//sup +/ and N/sub 4//sup +/ model }, keywords={ amorphous semiconductors carbon elemental semiconductors Fermi level hydrogen impurity electron states infrared spectra of inorganic solids nitrogen oxygen paramagnetic resonance of ions and impurities photoconductivity secondary ion mass spectra semiconductor thin films silicon semiconductor electron probe microanalysis SIMS IR absorption ESR hot-wall glow discharge decomposition electron spin resonance dark conductivity photoresponse Fermi level trapping state amorphous Si:H,O amorphous Si:H, C amorphous Si:H, N }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanSep91, author={Sentman, D.D. and Fraser, B.J.}, title={ Simultaneous observations of Schumann resonances in California and Australia: evidence for intensity modulation by the local height of the D region }, journal={Journal of Geophysical Research}, volume={96}, number={A9}, year={1991}, month={Sep}, pages={15973-84}, abstract={ Observations are presented of the horizontal magnetic component of Schumann resonance intensities as simultaneously measured at locations in California and Western Australia during two separate intervals September 2-17, 1989, and April 14-21, 1990. For both intervals, diurnal variations of the average magnetic power over the lowest three modes of the Schumann resonances showed substantially different temporal profiles at the California and Western Australia stations, with interstation correlations of 0.51 and 0.39, respectively. A method is demonstrated for determining from these observations the average local time variation of the height of the D region. This study suggests that such observations could be used to monitor the global totality and variability of lightning quantitatively and at time resolutions of the order of 10 min or less, in studies of global change }, keywords={ atmospheric techniques D-region ionosphere ionospheric electromagnetic wave propagation ionospheric techniques lightning ELF radiowave ionosphere D-region USA EM wave AD 1989 09 AD 1990 04 lightning measurement technique California Australia intensity modulation local height Schumann resonance diurnal variations }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{MeaudreApr91, author={Meaudre, R. and Meaudre, M. and Chanel, J.}, title={ Temperature dependence of the DC conductivity of undoped alpha -Si/sub 1-x/Ge/sub x/:H alloys: influence of metastability }, journal={Physical Review B (Condensed Matter)}, volume={43}, number={12}, year={1991}, month={Apr}, pages={9792-8}, abstract={ The effects of alloying on the shape of the Arrhenius plots of the DC conductivity of glow-discharge a-Si/sub 1-x/Ge/sub x/:H with 01 MeV electrons from the Earth's inner radiation belt at L100 km. For the unperturbed exponential profile the radial electric field E/sub r/ is nearly constant zE/sub r/ for z>or approximately=65 km. The Joule dissipation profile in this case has an absolute maximum at about 50 km and a smaller relative maximum at 90 km with a deep relative minimum at 65 km. The maximum dissipation thus occurs in the middle atmosphere, making the Schumann resonances particularly susceptible to conductivity perturbations in this region. The perturbations of this study comprise Gaussian-shaped enhancements or depressions of FWHM approximately=10 km impressed on the unperturbed profile. Eigenfrequencies and Q-values are computed for the full range of perturbation amplitudes 10/sup -3/-10/sup 3/ and altitudes 30-90 km. The perturbations induce overall eigenfrequency variations of +or-1.0, +or-1.5, and +or-2.5 Hz in the n=1, 2, and 3 modes, respectively, and Q-values spanning the range 2.5-11.0 }, keywords={ atmospheric electromagnetic wave propagation atmospheric radiation ionosphere ionospheric electromagnetic wave propagation radiowave propagation exponential atmosphere EM wave ELF radiowave emission ionosphere atmosphere propagation electrical conductivity perturbations Schumann resonances radial electric field Joule dissipation profile eigenfrequency variations }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{YangFeb83, author={Yang, S.H. and Lee, C.}, title={ Transport mechanism and its relationship with heterogeneity in a-Si:H }, journal={Solid State Communications}, volume={45}, number={7}, year={1983}, month={Feb}, pages={591-4}, abstract={ Hydrogen evolution and DC electrical conductivity measurement have been carried out for a-Si:H prepared by DC and RF glow discharge decomposition of silane. The authors show that the kink in log sigma vs 1/T plot can be explained in terms of the film heterogeneity. Kinks can appear or disappear after successive annealing depending on the specimens, and the upward shift in kink temperature by annealing is observed for the specimens showing kinks. These results are interpreted as being due to the structural and compositional change in heterogeneity caused by the diffusion and rearrangement of hydrogen }, keywords={ annealing electrical conductivity of amorphous semiconductors and insulators elemental semiconductors hydrogen plasma deposited coatings semiconductor thin films silicon surface diffusion Si:H amorphous state H evolution elemental semiconductor film structure transport mechanism composition heterogeneity DC electrical conductivity RF glow discharge decomposition annealing diffusion rearrangement }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{YungAug82, author={Yung, Y.L. and Demore, W.B.}, title={ Photochemistry of the stratosphere of Venus: implications for atmospheric evolution }, journal={Icarus (USA), Icarus}, volume={51}, number={2}, year={1982}, month={Aug}, pages={199-247}, abstract={ The photochemistry of the stratosphere of Venus was modeled using an updated and expanded chemical scheme, combined with the results of recent observations and laboratory studies. The authors examined three models, with H$_2$ mixing ratio equal to 2*10/sup -5/, 5*10/sup -7/, and 1*10/sup -13/, respectively. All models satisfactorily account for the observations of CO, O$_2$, O$_2$(/sup 1/ Delta ), and SO$_2$ in the stratosphere, but only the last one may be able to account for the diurnal behavior of mesospheric CO and the UV albedo. Photolysis of HCl in the upper stratosphere provides a major source of odd hydrogen and free chlorine radicals, essential for the catalytic oxidation of CO. Oxidation of SO$_2$ by O occurs in the lower stratosphere. It is shown that lightning in the lower atmosphere could provide as much as 30 ppb of NO/sub x/ in the stratosphere. The modeling reveals a number of intriguing similarities, previously unsuspected, between the chemistry of the stratosphere of Venus and that of the Earth }, keywords={ photochemistry planetary atmospheres Venus photolysis planetary atmosphere stratosphere Venus atmospheric evolution photochemistry H$_2$ mixing ratio CO O$_2$ SO$_2$ diurnal behavior mesospheric CO UV albedo HCl catalytic oxidation O lightning chemistry Earth }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ThumNov82, author={Thum, P.C. and Liew, A.C. and Wong, C.M.}, title={ Computer simulation of the initial stages of the lightning protection mechanism }, journal={IEEE Transactions on Power Apparatus and Systems}, volume={PAS-101}, number={11}, year={1982}, month={Nov}, pages={4370-7}, abstract={ This paper describes a computer program developed for the study of the growth of corona streamers from a lightning rod. The basic physical processes of electrical discharge are applied in the model. From results of computer studies, it was found that the determination of striking distance cannot rely solely on the state of growth of the upward streamer. The attractive effect of the lightning rod should be measured in terms of the rate of descent of the leader stroke with respect to the growth of the upward streamer. Additional studies were also made to determine the effect of structure height on striking distance }, keywords={ corona digital simulation lightning protection simulation initial stages lightning protection mechanism computer program corona streamers lightning rod }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanMar82, author={Sentman, D.D.}, title={ Thermal fluctuations and the diffuse electrostatic emissions }, journal={Journal of Geophysical Research}, volume={87}, number={A3}, year={1982}, month={Mar}, pages={1455-72}, abstract={ Persistent, weak-banded electrostatic emissions with mu V/m amplitudes have been observed in the magnetosphere at frequencies between the electron gyrofrequency omega /sub ce/ and upper hybrid frequency omega /sub uh/ when omega /sub ce/< omega /sub uh/. The suggestion that these low-level emissions are thermal fluctuations is quantitatively explored by using a simple hot-cold model for dayside electron distributions with density and temperature ratios n/sub c//n/sub h/>>1 and T/sub h//T/sub c/>>1. It is concluded that for typical dayside conditions the observed waves are weakly damped Bernstein-Harris modes whose spectral density and polarization perpendicular to the ambient magnetic field can be accounted for by the theory }, keywords={ atmospheric radiation magnetosphere thermal fluctuation radiowave emission EM wave plasma diffuse electrostatic emissions weak-banded magnetosphere hot-cold model Bernstein-Harris modes }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HolzworthNov81, author={Holzworth, R.H.}, title={ High latitude stratospheric electrical measurements in fair and foul weather under various solar conditions }, journal={Journal of Atmospheric and Terrestrial Physics}, volume={43}, number={11}, year={1981}, month={Nov}, pages={1115-25}, abstract={ Stratospheric electric field and conductivity measurements during a wide variety of weather and solar conditions are presented. These data are all from high latitude sites (>50 degrees N GG) in the months of either April or August. The vector electric field is determined by orthogonal double probes connected through high impedance inputs to differential electrometers. The direct conductivity measurement involves determining the relaxation time constant of the medium after refloating a shorted pair of separated probes. Vertical electric field data from several balloon flights with average duration of 18 h at ceiling in fair weather are shown to be well modeled by a simple exponential altitude dependent equation. Examples of solar flare and magnetospheric effects on stratospheric electric fields are shown. Data collected over electrified clouds and thunderstorms are presented along with a discussion of the thunderstorm related electric currents. Lightning stroke signatures in the stratosphere during a large thunderstorm are identified in the electric field data. Current surges through the stratosphere due to DC currents as well as the sferic are calculated. In nearly 1000 h of balloon data no direct solar influence is identified in these data except during major flares. However, variations in all three components of the electric field during magnetically active conditions are discussed }, keywords={ atmospheric electricity lightning magnetosphere meteorology solar-terrestrial relationships stratosphere thunderstorms high latitude stratospheric electrical measurements fair weather electrical conductivity measurements lightning stroke signatures stratosphere current surges solar terrestrial relationships solar flares foul weather solar conditions April August vector electric field orthogonal double probes relaxation time constant magnetospheric effects electrified clouds thunderstorm related electric currents DC currents sferic magnetically active conditions }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{HameedJun81, author={Hameed, S. and Paidoussis, O.G. and Stewart, R.W.}, title={ Implications of natural sources for the latitudinal gradients of NO/sub y/ in the unpolluted troposphere }, journal={Geophysical Research Letters}, volume={8}, number={6}, year={1981}, month={Jun}, pages={591-4}, abstract={ The authors investigate the latitudinal variations of the sources of tropospheric odd nitrogen (NO/sub y/) due to lightning discharges and stratosphere-troposphere exchange. By also considering the latitudinal variation of the removal rate in rainout they calculate the NO/sub y/ distributions in the troposphere using a one-dimensional model. The implications of the characteristic latitudinal gradients of NO/sub y/ due to these two sources are discussed in view of the GAMETAG measurements in the free troposphere }, keywords={ atmospheric chemistry atmospheric composition atmospheric movements lightning nitrogen compounds rain troposphere tropospheric odd N NO/sub y/ sources NO/sub y/ sinks rain NO/sub y/ concentration latitudinal gradients NO/sub y/ removal rate atmospheric movements unpolluted troposphere lightning discharges stratosphere-troposphere exchange rainout troposphere one-dimensional model GAMETAG measurements free troposphere }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanSep81, author={Sentman, D.D. and Edmiston, J.P. and Frank, L.A.}, title={ Instabilities of low frequency, parallel propagating electromagnetic waves in the Earth's foreshock region }, journal={Journal of Geophysical Research}, volume={86}, number={A9}, year={1981}, month={Sep}, pages={7587-97}, abstract={ The authors compute the electromagnetic dispersion relation for right- and left-hand circularly polarized low frequency waves propagating parallel and antiparallel to the upstream interplanetary magnetic field in the presence of both reflected and diffuse suprathermal ions. The electron and ion distribution function are modeled using the results of actual observations. It is found that the reflected ions destabilize the plasma most strongly at w approximately 0.1 Omega /sub i/ kby way of a resonant ion beam instability for waves propagating upstream, and by nonresonant firehose-like instability for downstream waves. The diffuse ion population also destabilizes the plasma. The growth times of the unstable waves are roughly 60 s and 150 s for those associated with the reflected and diffuse ions }, keywords={ magnetosphere magnetosphere bowshock plasma instability low frequency parallel propagating electromagnetic waves foreshock region electromagnetic dispersion relation circularly polarized upstream interplanetary magnetic field suprathermal ions ion distribution function }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanJun81, author={Sentman, D.D. and Kennel, C.F. and Frank, L.A.}, title={ Plasma rest frame distributions of suprathermal ions in the Earth's foreshock region }, journal={J. Geophys. Res. (USA), Journal of Geophysical Research}, volume={86}, number={A6}, year={1981}, month={Jun}, pages={4365-73}, abstract={ Presents rest frame ion distributions computed from three-dimensional observations of upstream suprathermal ions gained by the University of Iowa Quadrispherical Lepedea on ISEE-1. The observations are for a single inbound, midmorning pass starting upstream from the ion foreshock and continuing across the quasiparallel bow shock into the magnetosheath }, keywords={ magnetosphere plasma solar wind plasma distribution magnetosphere solar wind suprathermal ions Earth's foreshock region rest frame ion distributions upstream suprathermal ions Quadrispherical Lepedea ISEE-1 quasiparallel bow shock magnetosheath }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{JackmanDec80, author={Jackman, C.H. and Frederick, J.E. and Stolarski, R.S.}, title={ Production of odd nitrogen in the stratosphere and mesosphere: an intercomparison of source strengths }, journal={Journal of Geophysical Research}, volume={85}, number={C12}, year={1980}, month={Dec}, pages={7495-505}, abstract={ The study intercompares several sources of odd nitrogen (ON) in the stratosphere and mesosphere (middle atmosphere) so as to place galactic cosmic rays (GCRs) nuclear explosions, lightning, solar proton events (SPEs), relativistic electron precipitation, meteors, and the downward diffusion of NO from the thermosphere in their proper context relative to the oxidation of nitrous oxide. Use of published measurements of O/sub 3/ and N$_2$O show that the source of ON owing to the reaction of O(/sup 1/D)+N$_2$O peaks between 25 and 35 km and is by far the largest source in an annually, globally averaged sense with a magnitude of 4.5*10/sup 34/ molecules yr/sup -1/. At solar minimum the GCRs add about the same amount of ON as N$_2$O oxidation (1.7*10/sup 33/ molecules yr/sup -1/) for geographic latitudes greater than 50 degrees . Nuclear explosions in 1961 and 1962 added 1.1 and 2.2*10/sup 34/ NO molecules, respectively, to the total global ON content. SPEs produced more ON at latitudes above 50 degrees than did N$_2$O oxidation for the years 1958, 1959, 1960, and 1972. Analysis of available measurements shows the downward flux of NO from the thermosphere to between 8 and 33% of the integrated N$_2$O source. Large variations in measurements of ON should be expected at geographic latitudes above 50 degrees where the highly variable SPE source of ON is substantial. Because of the long lifetime of ON in the middle atmosphere, significant variations in its content may also be expected to occur at mid-latitudes }, keywords={ atmospheric chemistry atmospheric composition atmospheric movements diffusion geophysical aspects of cosmic rays mesosphere meteors nitrogen compounds nuclear explosions stratosphere stratosphere mesosphere middle atmosphere galactic cosmic rays nuclear explosions lightning solar proton events relativistic electron precipitation meteors O(/sup 1/D)+N$_2$O solar minimum N$_2$O oxidation integrated N$_2$O source atmospheric odd N production odd N source strengths N thermosphere NO diffusion NO downward flux NO$_2$ odd N sources latitude dependence AD 1955 to 1979 NO/sub 3/ altitude km 0000 to 0100 N$_2$O/sub 5/ HNO/sub 3/ }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{LevyJun80, author={Levy, H.I., II and Mahlman, J.D. and Moxim, W.J.}, title={ A stratospheric source of reactive nitrogen in the unpolluted troposphere }, journal={Geophysical Research Letters}, volume={7}, number={6}, year={1980}, month={Jun}, pages={441-4}, abstract={ A GFDL 3-D global generalized tracer field is adapted to provide a preliminary simulation of the reactive nitrogen (NOY) climatology in an unpolluted troposphere which has, as its sole source, downward transport of stratospheric NOY. The tracer field is scaled so that its downward cross-tropopause flux is balanced by the stratospheric production of NOY. While the model results show stratospheric NOY to be a significant source for the remote troposphere, they do not rule out additional contributions from either the long-range transport of combustion NOY or the in situ production by lightning. The model NOY climatology in the unpolluted troposphere shows a strong interhemispheric asymmetry due to greater downward NOY flux in the northern hemisphere and a steep drop off to a minimum in the tropics resulting from a combination of a model feature (tropical rainbelt, ITCZ, and Indian monsoon) which have been well documented in the real atmosphere }, keywords={ atmospheric chemistry nitrogen stratosphere troposphere stratospheric source unpolluted troposphere tracer field tropopause lightning tropics reactive N }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{WaldteufelMay80, author={Waldteufel, P. and Metzger, P. and Boulay, J.-L. and Laroche, P. and Hubert, P.}, title={ Triggered lightning strokes originating in clear air }, journal={Journal of Geophysical Research}, volume={85}, number={C5}, year={1980}, month={May}, pages={2861-8}, abstract={ During the 1978 campaign of the triggered lightning program at Saint-Privat d'Allier (France), simultaneous data from a movie camera, a coaxial shunt ammeter, a network of electric field mills and a weather radar, were collected during the initial phase of a particular triggered event. These data are shown to exhibit a high degree of consistency, leading to the conclusion that charges totaling several coulombs were present in cloudfree air in the vicinity of a stormy area }, keywords={ lightning triggered lightning France weather radar cloudfree air stormy area AD 1978 08 23 meteorology terrestrial electricity clear air lightning }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanOct79, author={Sentman, D.D. and Frank, L.A. and Gurnett, D.A. and Kurth, W.S. and Kennel, C.F.}, title={ Electron distribution functions associated with electrostatic emissions in the dayside magnetosphere }, journal={Geophysical Research Letters}, volume={6}, number={10}, year={1979}, month={Oct}, pages={781-4}, abstract={ Electron distribution functions constructed from ISEE-1 dayside observations of low energy magnetospheric electrons at low latitudes are presented. The authors choose examples corresponding to three distinct types of odd half harmonic electrostatic emissions observed by the plasma wave experiment on ISEE-1, and occurring between the electron cyclotron frequency f/sub ce/ and the upper hybrid frequency f/sub UH/. These are (a) intense (3/2)f/sub ce/ emissions; (b) weak (n+1/2)f/sub ce/ noise; and (c) intense f/sub UH/ waves at (9/2)f/sub ce/. No loss cone-like features are discernable in any of the distribution functions at the level of the instrument angular resolution. However, a weak ringlike feature, consisting of a small localized region in velocity space near 4*10/sup 9/ cm s/sup -1/ and alpha =90 degrees where delta f/ delta v perpendicular to >0, is found in the distribution function corresponding to the occurrence of the intense f/sub UH/ noise }, keywords={ atmospheric spectra magnetosphere electrostatic emissions dayside magnetosphere electron distribution function atmospheric spectra }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{BurkeSep79, author={Burke, W.J.}, title={ Plasma bubbles near the dawn terminator in the topside ionosphere }, journal={Planetary and Space Science}, volume={27}, number={9}, year={1979}, month={Sep}, pages={1187-93}, abstract={ The physical properties of plasma bubbles in the topside near the dawn terminator are investigated. It is assumed that the bubbles result from either a Rayleigh-Taylor or an E*B instability on the bottom side of the F-layer. While the E-region is in darkness, the top and bottom sides of the ionosphere are electrically decoupled and the motion of bubbles can be described by non-linear, two-dimensional theory. After sunrise, electric fields within the bubbles discharge through the conducting lower ionosphere. The upward drift of the bubbles is effectively halted. To achieve a dayside state of diffusive equilibrium the bubbles slowly begin to collapse from the bottom }, keywords={ atmospheric electricity atmospheric movements F-region ionosphere plasma plasma instability dawn terminator topside ionosphere plasma bubbles sunrise conducting lower ionosphere dayside state diffusive equilibrium bottomside F-region Rayleigh Taylor instability nighttime E-region magnetically aligned plasma depletions bubbles motion nonlinear two dimensional theory electric fields discharge bubbles upward drift spread-F ionosphere electrical decoupling ExB instability }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{KurthJun79, author={Kurth, W.S. and Frank, L.A. and Gurnett, D.A. and Burek, B.G. and Ashour-Abdalla, M. and Kennel, C.F. and Sentman, D.D.}, title={ A comparison of intense electrostatic waves near f/sub UHR/ with linear instability theory }, journal={Geophysical Research Letters}, volume={6}, number={6}, year={1979}, month={Jun}, pages={487-90}, abstract={ Intense electrostatic waves beyond the plasmapause have recently been identified at frequencies near the upper hybrid resonance frequency. In addition, the waves occur within a band at an odd, half-harmonic of the local electron gyrofrequency. These bands of electrostatic turbulence are among the most intense waves detected within the Earth's magnetosphere. Measurements obtained with the ISEE 1 plasma wave receiver show that the intense waves appear to be intensifications of an electrostatic cyclotron harmonic band near the upper hybrid resonance frequency. A straightforward explanation of intense waves at the upper hybrid resonance frequency exists in the electrostatic multi-cyclotron emission theory }, keywords={ magnetosphere plasma waves intense electrostatic waves linear instability theory plasmapause upper hybrid resonance frequency magnetosphere ISEE 1 plasma wave receiver }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ThomsenApr79, author={Thomsen, M.F. and Sentman, D.D.}, title={ Precipitation fluxes of energetic electrons at Jupiter: an estimated upper limit }, journal={Journal of Geophysical Research}, volume={84}, number={A4}, year={1979}, month={Apr}, pages={1409-18}, abstract={ Using Divine's (1976) model for the observed energetic electron intensity distribution in the inner Jovian magnetosphere to calculate phase space density profiles, the loss term is estimated for steady state radial diffusion in which the first and second adiabatic invariants are conserved. The assumption that all of the losses are due to precipitation into the ionosphere yields an upper limit for the precipitation flux at ionospheric altitudes. Using the calculated precipitation profiles, the total energy deposition in the ionosphere due to the precipitating particles is estimated and found to be less than a few tenths of an erg cm/sup -2/ s/sup -1/, which is of the same order as the energy deposited by energetic (E/sub e/>100 keV) electrons during the recovery phase of a terrestrial geomagnetic storm }, keywords={ Jupiter planetary atmospheres energetic electrons Jupiter upper limit Jovian magnetosphere phase space density profiles radial diffusion precipitation fluxes Jovian ionosphere }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{ChameidesJan79, author={Chameides, W.L.}, title={ Effect of variable energy input on nitrogen fixation in instantaneous linear discharges }, journal={Nature}, volume={277}, number={5692}, year={1979}, month={Jan}, pages={123-5}, abstract={ Atmospheric nitrogen oxides are a central issue in the photochemistry of the troposphere, stratosphere and urban atmosphere. The removal of nitrogen oxides by precipitation is a source of fixed nitrogen to the biosphere. Thus the nitrogen fixation rate by natural and anthropogenic discharges is of wide concern. While it is generally assumed that P, the molecules of NO produced per joule of discharge, is independent of the input energy, the analysis reported implies that P does vary with input energy. Thus care must be taken when extrapolating NO yields from small laboratory sparks to more energetic processes of potential geochemical significance }, keywords={ atmospheric chemistry lightning nitrogen compounds stratosphere troposphere variable energy input instantaneous linear discharges photochemistry troposphere stratosphere urban atmosphere biosphere NO N fixation atmospheric N oxides atmospheric precipitation lightning }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanJul78, author={Sentman, D.D. and Goertz, C.K.}, title={ Whistler mode noise in Jupiter's inner magnetosphere }, journal={Journal of Geophysical Research}, volume={83}, number={A7}, year={1978}, month={Jul}, pages={3157-67}, abstract={ The distinctive 'hat shape' of equatorial pitch angle distributions constructed from Pioneer 10 and 11 Jupiter observations of energetic electrons E/sub e/>21 MeV and E/sub e/>31 MeV at L=3 is examined from the point of view of pitch angle diffusion by resonant interaction with a band-limited spectrum of whistler mode noise. In this picture, the pitch angle profiles are consistent with whistler mode noise limited to frequencies below an upper cutoff frequency 2.80.5 gamma /sub max/, is approximately 2-10 kHz at L=3 }, keywords={ astronomical spectra Jupiter planetary atmospheres plasma whistlers equatorial pitch angle distributions energetic electrons pitch angle diffusion resonant interaction whistler mode noise upper cutoff frequency parallel propagating whistlers energetic electron distributions Jupiter inner magnetosphere wave/particle interactions whistlers band limited spectrum whistlers linear growth rates equatorial disc whistlers thermal plasma spatial distribution }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanJul78, author={Sentman, D.D. and Van Allen, J.A. and Goertz, C.K.}, title={ Correction to 'Recirculation of energetic particles in Jupiter's magnetosphere' }, journal={Geophysical Research Letters}, volume={5}, number={7}, year={1978}, month={Jul}, pages={621-2}, abstract={ During a recent comprehensive analysis of the pitch angle distributions of energetic particles in Jupiter's magnetosphere an intermittent error was found in the Pioneer 11 data reduction software. When present, this error caused a phase shift of 180 degrees in the assignment of spacecraft roll angles. The corrected analysis reveals significant proton anisotropies directed toward the planet in the southern hemisphere, contrary to the previous report (see ibid., vol.2, p.465-8 (1975)). In the northern hemisphere both proton and electron anisotropies are directed away from the planet, as reported previously. Hence, the earlier claim of direct evidence for the hypothesis of recirculation of energetic particles in the Jovian magnetosphere is invalidated. Nonetheless, it is considered that the hypothesis continues to have merit on the basis of indirect evidence, though the recirculation process must be weaker than envisioned originally and obscured by other processes }, keywords={ Jupiter planetary atmospheres pitch angle distributions intermittent error Pioneer 11 data reduction software proton anisotropies electron anisotropies Jupiter magnetosphere energetic particles recirculation }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{TuckOct76, author={Tuck, A.F.}, title={ Production of nitrogen oxides by lightning discharges }, journal={Quarterly Journal of the Royal Meteorological Society}, volume={102}, number={434}, year={1976}, month={Oct}, pages={749-55}, abstract={ The annual production of nitric oxide by lightning discharges is estimated to be 1.8*10/sup 35/ molecules, within rather large limits of uncertainty. Implications for the global budget of odd nitrogen species are cursorily examined. More data are needed to decide whether or not lightning-produced nitrogen oxides are transported in significant quantities to the stratosphere. Closer studies of the budget of nitrate in rainwater, and of air trajectories in large cumulonimbus storms, are also indicated }, keywords={ atmospheric composition lightning nitrogen compounds troposphere lightning discharges stratosphere rainwater air trajectories cumulonimbus storms NO production troposphere atmospheric odd N species NO$_2$ HNO/sub 3/ atmospheric composition }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanMar76, author={Sentman, D.D. and Van Allen, J.A.}, title={ Angular distributions of electrons of energy E/sub e/>0.06 MeV in the Jovian magnetosphere }, journal={Journal of Geophysical Research}, volume={81}, number={7}, year={1976}, month={Mar}, pages={1350-60}, abstract={ Results of an angular distribution of electron intensity data recorded by the University of Iowa experiment aboard Pioneer 10 are presented for the Jupiter encounter period November 26 through December 14, 1973. The data were from three directional particle detectors with effective integral energy thresholds of E/sub e/=0.06, 0.55, and 5.0 MeV, respectively. It is found that the central core of the magnetosphere for radial distances less than 12 R/sub J/ (Jovian radii) is dominated by pitch angle distributions strongly peaked at alpha =90 degrees , while the region of radial distances 12-25 R/sub J/ shows bidirectional and approximately equal maxima at alpha =0 degrees and 180 degrees . Bidirectional angular distributions in the magnetosphere out to the radius of the magnetopause strongly suggest quasi-trapping on closed field lines as the predominant situation. Substantial field-aligned unidirectional streaming was detected on only two occasions }, keywords={ electrons Jupiter planetary atmospheres electron intensity data Pioneer 10 Jupiter encounter period directional particle detectors effective integral energy thresholds pitch angle distributions closed field lines Jupiter magnetosphere magnetosphere central core electrons angular distribution quasitrapping bidirectional distributions peaked distributions field aligned unidirectional streaming }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{SentmanOct75, author={Sentman, D.D. and Van Allen, J.A. and Goertz, C.K.}, title={ Recirculation of energetic particles in Jupiter's magnetosphere }, journal={Geophysical Research Letters}, volume={2}, number={10}, year={1975}, month={Oct}, pages={465-8}, abstract={ A significant new finding from analysis of Pioneer 11 observations in the magnetosphere of Jupiter is that there is net streaming of both electrons E/sub e/>40 keV and E/sub e/>560 keV and protons 0.6121 million electron volts in the inner magnetosphere are shown to be compatible with the Kennel-Petschek whistler-mode instability. (iv) A diverse body of magnetospheric effects by the Jovian satellites is found. (v) Observations of energetic electrons in to a radial distance of 1.59 Jovian radii provide a fresh basis for the interpretation of decimetric radio noise emission }, keywords={ cosmic ray electrons cosmic ray protons Jupiter planetary atmospheres energetic particles Jovian magnetosphere positional distributions absolute intensities energy spectra angular distributions energetic electrons magnetodisc Jovian satellites energetic protons Kennel Petschek whistler mode instability Jupiter Pioneer 11 }, mynotes={UNREAD}, } /usr/tmp/citation.tmp.27694 @ARTICLE{Van-AllenSep74, author={Van Allen, J.A. and Baker, D.N. and Randall, B.A. and Sentman, D.D.}, title={ The magnetosphere of Jupiter as observed with Pioneer 10. I. Instrument and principal findings }, journal={Journal of Geophysical Research}, volume={79}, number={25}, year={1974}, month={Sep}, pages={3559-77}, abstract={ Reports on the first in situ observations of energetic electrons of energy E/sub e/>0.06 MeV in the magnetosphere of Jupiter during November-December 1973. The outer magnetosphere has the form of a thin, disclike, quasi-trapping region extending from about 20 to over 100 R/sub J/ (Jovian radii). This magnetodisc is confined near the magnetic equatorial plane and has approximate axial symmetry about the magnetic axis of the planet. The observations inside a radial distance of 12 R/sub J/ are well organized by a centered dipolar model of the planet's magnetic field with a tilt of 9.5 degrees +or-0.5 degrees to the rotational axis and with pole at a system III longitude of 230 degrees +or-3 degrees . Absolute omnidirectional intensities of electrons within the stable trapping region inside 20 R/sub J/ are given for five energy ranges E/sub e/>0.06, 0.55, 5.0, 21 and 31 MeV. One example is J(E/sub e/>21 MeV)=3.0*10/sup 8/ exp (-L/1.45)(cos/sup 6/ lambda )/4-3/sup 2/ lambda )/sup 1/2/)/sup m/2/ for 3.596% confidence) periodic activity in the frequency range 1-15 mHz (periods of 1-16 min) for data organized according to solar activity in H alpha , soft solar X-rays (2-12 AA), and several microwave frequencies (3-15 GHz) }, keywords={ radioastronomical observations solar radiofrequency radiation SHF 5 min periodic structure solar 2 cm emission solar data chromospheric oscillations power spectral analysis solar activity }, mynotes={UNREAD}, } @ARTICLE{van-AllenJan74, author={van Allen, J.A. and Baker, D.N. and Randall, B.A. and Thomsen, M.F. and Sentman, D.D. and Flindt, H.R.}, title={ Energetic electrons in the magnetosphere of Jupiter }, journal={Science}, volume={183}, number={4122}, year={1974}, month={Jan}, pages={309-11}, abstract={ Observations of energetic electrons (>or approximately=0.07 million electron volts) show that the outer magnetosphere of Jupiter consists of a thin disklike, quasi-trapping region extending from about 20 to 100 planetary radii (R/sub J/). This magnetodisk is confined to the vicinity of the magnetic equatorial plane and appears to be an approximate figure of revolution about the magnetic axis of the planet. Hard trapping is observed within a radial distance of about 20 R/sub J/. The omnidirectional intensity J/sub 0/ of electrons with energy >or approximately=21 million electron volts within the region 3