Future coastal sea level rise

If mid-century temperatures reach 2°C, global coastlines could rise by approximately 20 centimetres, but, due to global imbalances in ocean levels, 90% of coastal areas could experience even higher coastlines. And if temperatures rise by 5°C by 2100, as predicted by climate scenario RCP 8.5, coastlines could increase an average of 90 centimetres. Furthermore, an average of 80% of coastlines would have the potential to rise above 1.8 meters. An international team of researchers, among them Riccardo Riva of TU Delft, have published these findings in Proceedings of the National Academy of Sciences on November 7th.

According to this research, by 2040 with 2°C warming, more than 90% of coastal areas will experience sea level rise exceeding the global estimate of 20 cm, with up to 40 cm expected along the Atlantic coast of North America and Norway due to ocean dynamics.

Beyond two degrees

If the temperature rises by more than 2°C, indicated by several climate scenario's to happen sometime around halfway this century, sea level will rise at a much higher rate. In one of the most extreme cases, 5°C by 2100 (climate scenario RCP 8.5), probably by as much as 90 centimetres. For many coastal cities, there is even a 5% chance that sea level will rise more than 1,8 meters (1.87 m for Rotterdam up to 2.2 m for the American east coast).

Not much time

Due to gravitational differences and the influence of ice melt form Antarctica, only the southern part of South America (Chile, Argentina, Uruguay and part of Brazil) will experience a significantly smaller sea level rise. The scientists warn that coastal cities and vulnerable tropical coastal ecosystems will have very little time to adapt to the fast sea level rise these predictions show, in scenarios with global warming above two degrees.

More information:
phys.org/news/2016-11-simulati … -coastal-cities.html

Provided by Delft University of Technology