Assessment of August 11, 2021 Bozkurt Flood Disaster With Sentinel-2 Satellite Images, Turkey

Flood disasters caused by regional or local heavy rainfalls have become one of the most severe types of climaterelated natural disasters. Urban areas in Turkey frequently suffer from floods, which are common climate-related disasters. For example, heavy rainfall for three days in Kastamonu province, northern Turkey, caused a catastrophic flood event on August 11, 2021 in Bozkurt district. At least 71 people have died, many houses and shops were severely damaged, two apartments have collapsed, and the flood dragged many cars.

In this study, an automatic change detection processing for rapid flood mapping in Sentinel-2 data by analyzing the Natural Color and Normalized Difference Water Index (NDWI) images over the Bozkurt district and Ezine Valley demonstrate the effectiveness and efficiency of the remote sensing data. Natural Color images emphasized the flooding impact in Bozkurt district and transportation of mudflows through the Ezine Valley into the sea. Additionally, evaluating the NDWI data shows that approximately 1.61 km2 drought by severe flood event caused by heavy rainfall in August 2021. Bozkurt flood and similar disasters draw attention to the fact that weather is becoming more severe and more frequent due to anthropogenic global climate change.