Projections of Global Delta Land Loss From Sea-Level Rise in the 21st Century

River deltas will likely experience significant land loss because of relative sea-level rise (RSLR), but predictions have not been tested against observations. Here, we use global data of RSLR and river sediment supply to build a model of delta response to RSLR for 6,402 deltas, representing 86% of global delta land. We validate this model against delta land area change observations from 1985-2015, and project future land area change for IPCC RSLR scenarios. For 2100, we find widely ranging delta scenarios, from +94 +/- 125 (2 s.d.) km(2) yr(-1) for representative concentration pathway (RCP) 2.6 to -1,026 +/- 281 km(2) yr(-1) for RCP8.5. River dams, subsidence, and sea-level rise have had a comparable influence on reduced delta growth over the past decades, but if we follow RCP8.5 to 2100, more than 85% of delta land loss will be caused by climate-change driven sea-level rise, resulting in a loss of similar to 5% of global delta land.

Automated summary

Research indicates that river deltas are facing significant land loss due to climate-change driven sea-level rise, with future projections showing a gloomy outlook.