Abstract: To acquire accurate soil moisture information in time and space, soil moisture information (surface soil moisture SSM and profile soil moisture PSM) from multiple satellites (SMOS, ASCAT, ESA CCI and SMAP) is compared with PSM simulations from a distributed hydrological model. The comparison is developed at daily scale and catchment/grid scale in a humid catchment (Qujiang catchment) and a semiarid catchment (Yiluohe catchment) in China. Results indicate that SMAP PSM show higher consistency with simulated PSM when the performance of simulated PSM is high in a catchment, with the correlation coefficient reaching 0.8. Thus, the accuracy of SMAP is regarded to be relatively higher compared to other satellite products. The research offers guidance and practical values for acquiring accurate soil moisture information in time and space.

Key words: surface soil moisture, profile soil moisture, satellite products, distributed hydrological model, spatial and temporal comparison