MultiRS flood mapper: a google earth engine application for water extent mapping with multimodal remote sensing and quantile-based postprocessing

Abstract

There is a growing interest in developing GEE applications to improve the reusability of GEE scripts and reduce manual effort for water-body extraction. Right now, there is a need for GEE applications that can serve both remote sensing experts and non-technical persons. Those applications should also be powerful enough to handle the entire water body extraction workflow and can handle various geomorphic and geospatial conditions. Given these needs and challenges, this study presents the MultiRS Flood Mapper, a GEE application that integrates multimodal remote sensing imageries, advanced dynamic thresholding algorithms, and a recently introduced powerful postprocessing approach – Quantile-Based Filling & Refining, to improve classification results under the influence of dense vegetation and cloud, and in regions with constrained hydraulic conditions. The MultiRS Flood Mapper comes with a self-explanatory and user-friendly interface with most computation modules fully automated, allowing the application great potential to serve both technical and non-technical users.