1. aGlobal Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, MD, USA
2. bScience Systems and Applications, Inc., Lanham, MD, USA
3. cHydrology and Remote Sensing Laboratory, Agricultural Research Service, USDA, Beltsville, MD, USA
4. dDepartment of Earth and Environmental Sciences, KU Leuven, Heverlee, Belgium
5. eNTSG, University of Montana, Missoula, MT, USA