Global probabilistic projections of extreme sea levels show intensification of coastal flood hazard

Global warming is expected to drive increasing extreme sea levels (ESL) and flood risk along the world’s coastlines. Probabilistic projections of ESL are presented for this century taking into consideration changes in mean sea level, tides, wind-waves, and storm surges. A moderate-emission-mitigation-policy scenario and a business as usual scenario are considered.  Rising ESLs are mostly driven by thermal expansion, followed by contributions from ice mass-loss from glaciers, and ice-sheets in Greenland and Antarctica. Under these scenarios ESL rise would render a large part of the tropics exposed annually to the present-day 100-year event from 2050. By the end of this century this applies to most coastlines around the world, implying unprecedented flood risk levels unless timely adaptation measures are taken.

In this study, scientists used the JRC's LISCoAsT – Large scale Integrated Sea-level and Coastal Assessment Tool, under the framework of the PESETA project and in cooperation with the European Commission's department for climate action.