Mapping Sea Level Rise Exposure in Tacloban City, Philippines

Keywords: sea level rise, coastal flooding
Session Type: Virtual Poster
Day: Wednesday
Session Start / End Time: 4/7/2021 09:35 AM (Pacific Time (US & Canada)) - 4/7/2021 10:50 AM (Pacific Time (US & Canada))
Room: Virtual 51

Abstract

This study demonstrates hazard exposure mapping of potential sea-level rise for Tacloban City, Philippines. It explores how the use of different digital elevation model (SRTM, CoastDEM, Lidar DEM) and different SLR + storm-surge scenarios would effect population and building exposure to coastal flooding. The hazard modelling was done in GIS using a raster-based bathtub fill and static approach. Exposure mapping used latest census population (2015) and building footprint from OpenStreetMap. Hazard exposure is an important input in vulnerability and risk assessment that often informs adaptation planning and comprehensive planning. This study confirmed that the use of different data sources can affect hazard exposure assessments. Interestingly, even if for a particular scenario the coastal hazards will only expose less than one-hundredth of a percent (.003%) of the land area, it will affect more than half (64%) of the population. Such understanding of hazards and exposure are usually used as a basis for planning and policy decisions such as building sea-wall and "no build zone" in the case of Tacloban City. This calls for the use of the best available information and advancing risk research where sea level rise is usually under-considered particularly for Comprehensive Land Use Planning in the Philippines.