Operational surface soil moisture retrieval by c-band SAR imagery in a semi-arid environment

The work focuses on a development of a fully operational approach for surface soil moisture (SSM) monitoring and mapping in the semi-arid environment. A brief background of the work is described in the Section 1. The paper then carefully describes the rationale and the working procedures of the approach in Section 2 and Section 3 respectively. Model performance is demonstrated in Section 4 for both bare soil fields and crop fields. Promising results are noticed (RMSE= 5.76 vol. %) for bare fields for a large range of in situ SSM condition and (RMSE= 4.51 vol. %) crop fields for in situ SSM lower than 20 vol. %. A further application is also added to show the model's capability in regional SSM mapping.