“…Soil moisture is a key element in controlling land surface energy partitioning, surface water budget, and vegetation transpiration and carbon assimilation. Knowledge regarding the regional/global soil moisture state is essential for understanding, modeling, and forecasting of the weather/climate [e.g., Chen and Avissar, 1994;Koster et al, 2004;Miralles et al, 2014], flood/drought early warning and monitoring [e.g., Hirschi et al, 2011;Massari et al, 2014], and crop yield estimation [e.g., Ines et al, 2013;Alamilla-Magaña et al, 2016]. However, in situ observations are too sparse to provide large-scale spatiotemporal features of soil moisture.…”