Detection of soil moisture anomalies based on Sentinel-1

Publication date: Available online 30 November 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Felix Greifeneder, Erick Khamala, Degelo Sendabo, Wolfgang Wagner, Marc Zebisch, Hussein Farah, Claudia NotarnicolaAbstractActive and passive microwave remote sensing has evolved into a well-accepted and widely used method for the spatially continuous, coarse to medium resolution mapping of the surface soil moisture content (SMC). Presently, the exploitation of high-resolution data is less mature. Sentinel-1 is a high-resolution Synthetic Aperture Radar (∼5 by 20 m), which acts as the basis for mapping of SMC in this study. There aren’t any other comparable SAR missions currently available whose data can be accessed and used for free.One of the applications for SMC measurements is connected to the relationship between SMC anomalies and natural hazards such as droughts, flooding, or land-slides. A requirement for the detection and quantification of an anomaly is a long time-series (often 10 to 30 years) to derive a reference value. Herein lies one of the issues of Sentinel-1 based SMC mapping – at the time of writing, the Sentinel-1 time-series spanned a period of approximately 3.5 years.We introduce an approach to overcome this problem and enable the Sentinel-1 based SMC anomaly detection. The method is based on a cross-calibration between Sentinel-1 SMC estimations and coarse resolution (∼30 km) modelled SMC from the Global Land Data Assimilation Syste...
Source: Physics and Chemistry of the Earth, Parts ABC - Category: Science Source Type: research