1. a Center for Climatic Research, University of Wisconsin–Madison, Madison, Wisconsin
2. b Space Science and Engineering Center, Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin–Madison, Madison, Wisconsin
3. c Department of Earth and Planetary Sciences, The Johns Hopkins University, Baltimore, Maryland
4. d NASA Marshall Space Flight Center, Earth Science Branch, Huntsville, Alabama
5. e Hydrological Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland
6. f Hydrology and Remote Sensing Laboratory, USDA, Agricultural Research Service, Beltsville, Maryland