A Combined Study of Flood Propagation Mapping, Using Sentinel-1 and Landsat-8 Data. A Case Study From River Evros, Greece

Floods are suddenly and temporary natural disasters, which influence equally important the society and the natural environment, affecting areas that are not normally covered by water. In the context of flood mapping, different remote sensing techniques may contribute in a sufficient and effective way. This paper deals with mapping the spread of water bodies from natural levees of the river Evros and therefore the flood event on the surrounding areas of the river. In this work, radar data from Sentinel-1 mission as well as optical data from Landsat-8 were utilized. Specifically, Sentinel-1 data before flood events were treated with respectively during flood, yielding an image which reflects the propagation of the event. Moreover, Landsat-8 data were acquired with the aim of identifying and mapping of flooded areas, utilizing the Normalized Difference Water Index calculation. The results of the two methods were compared and flooded areas were evaluated.