EOMF-07. End-to-end Framework for Future Inundation Scenarios of Coastal Cities with High Resolution Digital Surface Models

Abstract
More than 600 million people live in areas vulnerable to the effects of future global sea level rise, so-called low elevation coastal zones (LECZs), defined as regions less than ten meters above mean sea level. Many cities in LECZs have large populations and rapid growth of people and infrastructure, but knowledge of the latter is often not well known or not up-to-date. Using commercial WorldView stereo-imagery acquired through NASA we create high resolution digital surface models (DSMs); these form the basis for our impact studies of the effects of future sea level change on coastal cities across the world. We produce high resolution (2 m) strips of DSMs using the Surface Extraction with TIN-based Search-space Minimization (SETSM) algorithm on CU's high performance computing resources. These strips are then mosaicked and co-registered to ICESat-2, to reduce the relative and absolute vertical errors, respectively. Using the IPCC’s AR6 projections for future regional sea level change under different Shared Socioeconomic Pathways (SSPs), we provide projections of future inundation scenarios for several hundred cities across the world. We do this by taking a gridded mean sea surface as a baseline mean sea level, onto which we add perigean tide values (from FES2014), and the aforementioned sea level change; we do this with and without taking connectivity to the sea into account. As the extent of large coastal cities can be upwards of 100 km along the coast, we incorporate the spatial variability of mean sea level, its change, and vertical land motion when computing our inundation projections.