Mesoscale soil moisture estimation from SAR data using subscale landuse information

The variation of soil moisture and its spatial pattern within a watershed is highly dynamic. Hydrological processes, such as runoff production or evapotranspiration, largely depend on the spatial distribution of soil water content, which is impossible to measure on ground over larger areas. ENVISAT ASAR image products have high potential for the generation of soil moisture maps. Especially wide swath images, covering large areas with adequate spatial and temporal resolution, are very interesting from the user point of view. The quality of the soil moisture products, derived from SAR data mainly depends on the information about the land cover. Especially for mesoscale images, an adequate parameterisation of the land cover is difficult. We therefore investigate the effect of different landuse parameterisations on the accuracy of mesoscale soil moisture inversion. An algorithm for the derivation of mesoscale soil moisture maps is proposed.