Given the present-day rate of global sea-level rise, remaining marshes in the Mississippi Delta are likely to drown, according to a new Tulane University study.
A key finding of the study, published in Science Advances , is that coastal marshes experience tipping points, where a small increase in the rate of sea-level rise leads to widespread submergence.
The loss of 2,000 square miles (5,000 km 2 ) of wetlands in coastal Louisiana over the past century is well documented, but it has been more challenging to predict the fate of the remaining 6,000 square miles (15,000 km 2 ) of marshland.
The study used hundreds of sediment cores collected since the early 1990s to examine how marshes responded to a range of rates of sea-level rise during the past 8,500 years.
“Previous investigations have suggested that marshes can keep up with rates of sea-level rise as high as half an inch per year (10 mm/yr), but those studies were based on observations over very short time windows, typically a few decades or less,” said Torbjörn Törnqvist, lead author and Vokes Geology Professor in the Tulane […]