Bio: Dr. Singer, Professor (Emeritus) of environmental sciences at the University of Virginia, is the founding president of the Fairfax-based Science & Environmental Policy Project. SEPP is a non-profit educational association of scientists concerned with providing a sound scientific base for environmental policies. Singer has held several academic and governmental positions, including as the first director of the U.S. Weather Satellite Service (now part of NOAA), deputy assistant administrator for policy of the Environmental Protection Agency, and most recently, chief scientist of the U.S. Department of Transportation. He devised the instrument used to measure stratospheric ozone from satellites and was first to point to and calculate the human- based production of atmospheric methane, an important greenhouse gas and source of stratospheric water vapor. He is the author of many scientific articles and the book "Hot Talk, Cold Science: Global Warming's Unfinished Debate," now in its second edition.