Journal article Embargoed Access

A global analysis of subsidence, relative sea-level change and coastal flood exposure

Robert J. Nicholls, Daniel Lincke, Jochen Hinkel, Sally Brown, Athanasios T. Vafeidis, Benoit Meyssignac, Susan E. Hanson, Jan-Ludolf Merkens & Jiayi Fang

Climate-induced sea-level rise and vertical land movements, including natural and human-induced subsidence in sedimentary coastal lowlands, combine to change relative sea levels around the world’s coasts. Although this affects local rates of sea-level rise, assessments of the coastal impacts of subsidence are lacking on a global scale. Here, we quantify global-mean relative sea-level rise to be 2.5 mm yr−1 over the past two decades. However, as coastal inhabitants are preferentially located in subsiding locations, they experience an average relative sea-level rise up to four times faster at 7.8 to 9.9 mm yr−1. These results indicate that the impacts and adaptation needs are much higher than reported global sea-level rise measurements suggest. In particular, human-induced subsidence in and surrounding coastal cities can be rapidly reduced with appropriate policy for groundwater utilization and drainage. Such policy would offer substantial and rapid benefits to reduce growth of coastal flood exposure due to relative sea-level rise.

Embargoed Access

Files are currently under embargo but will be publicly accessible after September 8, 2021.

37
4
views
downloads
Views 37
Downloads 4
Data volume 20.6 MB
Unique views 25
Unique downloads 2

Share

Cite as