Predicting marsh vulnerability to sea-level rise using Holocene relative sea-level data.

ABSTRACT: Tidal marshes rank among Earth's vulnerable ecosystems, which will retreat if future rates of relative sea-level rise (RSLR) exceed marshes' ability to accrete vertically. Here, we assess the limits to marsh vulnerability by analyzing >780 Holocene reconstructions of tidal marsh evolution in Great Britain. These reconstructions include both transgressive (tidal marsh retreat) and regressive (tidal marsh expansion) contacts. The probability of a marsh retreat was conditional upon Holocene rates of RSLR, which varied between -7.7 and 15.2?mm/yr. Holocene records indicate that marshes are nine times more likely to retreat than expand when RSLR rates are ?7.1?mm/yr. Coupling estimated probabilities of marsh retreat with projections of future RSLR suggests a major risk of tidal marsh loss in the twenty-first century. All of Great Britain has a >80% probability of a marsh retreat under Representative Concentration Pathway (RCP) 8.5 by 2100, with areas of southern and eastern England achieving this probability by 2040.

SUBMITTER: Horton BP 

PROVIDER: S-EPMC6043595 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature