Modelling L band backscattering of wheat in Argentinean Pampas and its application to soil moisture retrieval

In this paper a data base of L band backscattering simulations, based on the application of a discrete scattering model and detailed ground truth collected over Argentinean wheat fields, is tested. The simulations are directly compared against backscattering measurements collected over single fields. Then the scattering model is used to tune a semi empirical and manageable model function. Finally this function, jointly with a multi-temporal algorithm, is used for soil moisture retrieval and results are tested against an independent set of measurements. The site used for training and validation is located in the Pampas region, which will be continuously monitored in the framework of the SAOCOM (SAtélite Argentino de Observación COn Microondas) programme. In general, both the direct model and the retrieval algorithm produce consistent results. However, variation in the azimuth angle of observation produces appreciable effects, and some discrepancies are observed for radar observations collected just after a rainfall. These issues deserve further investigation with a larger amount of experimental data.