1. Hydrological Sciences Laboratory, Code 617, NASA Goddard Space Flight Center, Greenbelt, MD 20771, U.S.A.
2. Science Systems and Applications, Inc., Lanham, MD 20706, U.S.A.
3. Mesoscale Atmospheric Processes Laboratory, Code 612, NASA Goddard Space Flight Center, Greenbelt, MD 20771, U.S.A.
4. Center for Satellite Applications and Research, NOAA National Environmental Satellite, Data, and Information Service, College Park, MD 20740, U.S.A.
5. Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20740, U.S.A.
6. Cryospheric Sciences Laboratory, Code 615, NASA Goddard Space Flight Center, Greenbelt, MD 20771, U.S.A.