Flood mapping using sentinel-1 SAR imagery: case study of the November 2017 flood in Penang

Abstract

The Sentinel-1 SAR image by the Europe Space Agency (ESA) in the Copernicus Programme is an open source data which offers good data to develop flood inundation mapping. The flood inundation mapping is essential information for local authority personals or researchers to develop flood inventory map. The objective of this study is to develop a flood inundation mapping on November 2017 event to assess its use as potential flood inventory mapping data in Penang. The threshold method was carried out using Sentinel-1 image to extract the flood map. This method is pixel value used to separate the grey image into two parts. The flooded and non-flooded areas can be identified by separating the backscatter lower than the threshold value. The results revealed that the flood inundation maps are able to be extracted out from Sentinel-1 images.