Predicting marsh vulnerability to sea-level rise using Holocene relative sea-level data
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Salt marshes around Great Britain could be covered by rising seas this century.
Tidal marshes provide natural protection against stormy seas and are valuable habitats for fisheries. But their vulnerability to rising seas is contested: some studies suggest these wetlands are already being submerged, while others suggest that prolonged flooding gives sediment more time to settle, enabling the marshes to hold their ground.
A team including researchers from Nanyang Technological University in Singapore studied geological records of salt-marsh evolution around the coast of Britain as the sea level rose and fell over the last 12,000 years. They found that marshes started shrinking when sea level rose faster than 7 millimetres per year.
Using climate models, the researchers predict that, if greenhouse-gas emissions continue to increase, Britain’s vital salt marshes will start disappearing under rising seas by 2100.
- Nature Communications 9, 2687 (2018). doi: 10.1038/s41467-018-05080-0