Cool Scientists
Dr. Stephen Warren
Name: Stephen Warren
Born: 1945
Organization: University of Washington, Department of Atmospheric Sciences and Geophysics
Cool Science: Physical Chemist
Who Am I:
I am a Professor of Atmospheric Sciences and of Earth and Space Sciences at the University of Washington in Seattle. My research interest is the interaction of solar radiation with snow, clouds, and sea ice, and their role in climate. I have carried out fieldwork in the Antarctic Ocean, on the East Antarctic Plateau, and in Greenland.
My Cool Research:
Small light-absorbing carbonaceous particles ("black carbon", or soot) are produced by incomplete combustion in burning of fossil fuels or biomass (e.g. forest fires). The particles are carried for several days by the atmosphere before being scavenged by raindrops or snow crystals. Parts-per-billion amounts of soot can enhance the absorption of sunlight by snow, potentially affecting the Arctic climate and the stability of sea ice. In our previous work, the soot content of snow on land and sea in the western Arctic was measured in 1984, suggesting possible reductions of albedo (reflectance) of 0-4%. We are now updating the earlier survey and making it more comprehensive. We hope to cover the Siberian arctic, which was not sampled in the earlier work. Thus the snow samples collected from Chukotka along the dogsled trek will be especially valuable for our project. We prefer for snow samples to be taken during March-May (i.e., near the time of maximum snow depth). Snow samples will be taken at several vertical levels through the snow pack. At the end of the dogsled trek, the snow samples will be taken to Anadyr and stored in a freezer. Warren will travel to Anadyr in June to analyze them. The snow will be melted and filtered; the filters are then analyzed for light transmission at four wavelengths to separate the contributions to absorption by soot and dust. The snow must be kept frozen until immediately before filtering, to avoid losses of soot to the container walls and to avoid algal growth.
Website: http://www.atmos.washington.edu/sootinsnow/
My Cool Publications:
90 cited publications, with 4700 citations, as of January 2003.
My Cool Awards:
Fellow, American Meteorological Society, 2005; Fellow, American Association for the Advancement of Science, 1998; Gerbier-Mumm Award, World Meteorological Organization, 1988; First departmental teaching award, Dept. of Atmospheric Sciences, 1989, and Dean's Award for Exceptional Teaching, College of Arts and Sciences, 1990, Univ. of Washington; Namesake, Warren Ridge (Antarctica), 2001; Special Creativity Award, Div. of Atmospheric Sciences, National Science Foundation, 2002; Highly Cited Author, Institute for Scientific Information, 2003.
Other Cool Stuff:
Council Member, International Glaciological Society; Review Panel, NSF Polar Glaciology, 2001; Committee on Atmospheric Radiation, American Meteorological Society, 1998-2001; International Commission on Polar Meteorology, 1997-2005; Station Science Leader, South Pole Station, 1992.
