Ali Behrangi¹, Yang Song¹, George John Huffman², Robert F Adler³, Daqing Yang⁴, David T Bolvin⁵ and Eric Nelkin⁵, (1)University of Arizona, Department of Hydrology and Atmospheric Sciences, Tucson, AZ, United States, (2)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (3)University of Maryland, College Park, MD, United States, (4)National Hydrology Research Center, Environment Canada, Saskatoon, SK, Canada, (5)Science Systems and Applications, Inc., Lanham, MD, United States