A constantly updated flood hazard assessment tool using satellite based high resolution land cover dataset within Google Earth Engine

Abstract

Abstract This work aims to develop a constantly updated flood hazard assessment tool that utilizes readily available datasets derived by remote sensing techniques. It is based on the recently released global land use/land cover (LULC) dataset Dynamic World, which is readily available as an open data source within Google Earth Engine platform. The tool is updated constantly following the release rate of Sentinel-2 images, i.e., every 2 to 5 days depending on the location and provides a near real time detection of flooded areas. Specifically, it identifies how many times each 10 m pixel is characterized as flooded for a selected time period. In order to investigate the fruitfulness of the proposed tool, we compared the outcome of the tool against the Regional Flood Hazard Maps developed in the frames of the EU Water Framework Directive, and we found several inconsistencies of the two approaches. Besides, a new metric is proposed, named Maximum Potential Economic Loss, in order to assess the socioeconomic implications of the flooding. The innovative character of the presented methodology consists of the use remotely sensed-based datasets, becoming available at increasing rates, for developing an operational instrument which defines and updates the flood hazard zones in real-time required.