Comparing soil moisture retrievals from SMOS, ASCAT and AMSR-E over the Pampas plains

Currently, there are several satellite systems of coarse spatial resolution that observe the Earth in the microwave region of the electromagnetic spectrum. They provide operational soil moisture products, among them AMSR-E/LPRM, ASCAT, SMOS. This work aims at answering the following questions: 1) are these products comparable?, 2) how does one evaluate their quality and if they are realistic in view of the lack of in situ data at their spatial scale? To answer these questions, we have analyzed time series of the soil moisture product for the different systems mentioned above. Two types of analysis were performed: a) analysis of spatial anomalies and their correlations, b) analysis of temporal anomalies and application of the Triple Collocation method for error estimation. Land cover maps, precipitation data and NDVI time series were used as ancillary information.