Floodplain inundation Mapping using SAR Scattering Coefficient Thresholding and Observed Discharge Data

Inundation area time series are important for wetlands monitoring and hydrological model validation. This study is conducted in Biebrza floodplain, which is a natural wetland with complex inundation generation processes. In order to map 2014-2018 series of inundation in the floodplain we test our automatic thresholding method on Sentinel 1 data. The threshold value is optimized using correlation of the inundation area with observed discharge at the floodplain outlet. The inundation maps match well the MODIS 500m reflectance data used as a reference, whereas, the total inundated area per Sentinel 1 image match well the observed discharge pattern. Unfortunately, this approach was unable to identify inundation in remote parts of the floodplain, what may have few reasons and needs further investigation.