Soil moisture retrieval from dense temporal series of C-band SAR data over agricultural sites

This paper investigates the use of dense time series of C-band SAR data (i.e. acquired with revisit time within 1–2 weeks) for the retrieval of volumetric soil moisture content (mv) underneath agricultural crops. Its final aim is to contribute at assessing retrieval strategies for monitoring agricultural areas using near future frequent-revisit SAR missions, such as the forthcoming European Sentinel-1. A recently developed mv retrieval algorithm is firstly presented and then applied to a time series of ASAR HH and HV data collected in 2006 over the agricultural DEMMIN site (Germany). The assessment of the algorithm is provided by comparing the SAR-derived mv maps over the DEMMIN site with hydrologically modelled mv maps. Results indicate that mv can be retrieved with accuracy ranging between 5% and 6%.