Sea-level Rise Increases the Frequency of Nuisance Flooding in Coastal Regions

Friday, 18 December 2015
Poster Hall (Moscone South)
Hamed Moftakhari Rostamkhani1, Amir Aghakouchak2, Brett F Sanders1, David Feldman3, William Sweet4, Richard Matthew5, Adam Luke5 and FloodRISE, (1)University of California Irvine, Civil and Environmental Engineering, Irvine, CA, United States, (2)University of California Irvine, The Henry Samueli School of Engineering, Irvine, CA, United States, (3)University of California Irvine, Planning, Policy and Design, Irvine, CA, United States, (4)NOAA, Boulder, CO, United States, (5)University of California Irvine, Irvine, CA, United States
The global warming-drivensea-level rise (SLR) posesa serious threat for population and assets in flood-prone coastal zones over the next century. The rate of SLR is accelerated in recent decades and is expected to increase based on current trajectories of anthropogenic activities and greenhouse gas emissions. Over the 20th century, an increase in the frequency of nuisance (minor) flooding has been reported due to the reduced gap between tidal datum and flood stage. Nuisance flooding (NF), however non-destructive, causes public inconvenience, business interruption, and substantial economic losses due to impacts such as road closures and degradation of infrastructure. It also portends an increased risk in severe floods. Here we report substantial increases in NF along the coasts of United States due to SLR over the past decades. We then take the projected SLR under the least and the most extreme representative concentration pathways (e.gRCP2.6 and RCP 8.5) to estimate the increase in NF in the near- (2030) and mid-term (2050) future. The results suggest that projected SLR will cause up to two-fold more frequent NF by 2050, compared with the 20th century. The projected increase in NF will have significant socio-economic impacts and pose public health risks especially in rapidly urbanized coastal regions.