Mapping Floods Using SAR Polarimetry in Imola, Italy

In flood management practices, the identification of areas inundated by flood water is vital in mitigating future events. SAR data can be used to map and extract flood extent. The use of Polarimetric SAR in change detection between datasets acquired before and during floods can be used for rapid and accurate flood mapping. Polarimetric data improves the accuracy of the detection of floods. Four change detection methods (Optimization of Power Difference (OPDiff), Power Ratio (OpRatio), difference in Cloude-Potier eigenvalues and difference in backscatter intensity) were used in change detection for flood event in Imola, Italy. Dual-Pol Sentinel-1 data was analysed and the accuracy of the detection was evaluated against PlanetScope optical data. The results show that difference in Cloude-Potier second eigenvalue had the highest accuracy which was identical to difference in VH data.