*Miguel O Roman^1,3、Chris Justice²、Sadashiva Devadiga³ (1.Leidos, Inc, 1750 Presidents St, Reston, VA 20190, USA、2.Department of Geographical Sciences, University of Maryland, 2181 LeFrak Hall, College Park, MD 20742, USA、3.Terrestrial Information Systems Laboratory, Code 619, NASA/Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA)