SES Alum Dr. Apoorva Shastry and Professor Michael Durand recently published an article in AGU: Geophysical Research Letters titled, "Water Surface Elevation Constraints in a Data Assimilation Scheme to Infer Floodplain Topography: A Case Study in the Logone Floodplain". Read the full article here!
"Floods are the most damaging natural hazard, affecting millions of people around the world. Flood models predict where and how floods occur, their timing and duration, etc., using inputs such as rainfall, magnitude of river flow and ground elevation map. Ground elevation map is arguably the most important input for flood models. Ground elevation data is usually used in the form of digital elevation models (DEMs), which are essentially grid cells with ground elevation values. In the developed world, very precise DEMs are available. However, globally available open access satellite DEMs are not accurate and are not suitable for use in flood models. Some information about the ground elevation map can be derived from satellite observed flood maps. We develop a novel method to efficiently integrate flood model simulations and flood remote sensing in a data assimilation scheme to improve DEMs. Basically, we use the fact that the elevation of a flooded region is lower than the dry region surrounding it. We test the algorithm in the Logone Floodplain in Cameroon. The updated DEM from this method produces more accurate flood maps when used in a flood model."