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.
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 km2) 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 km2) 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 Department of Earth and Environmental Sciences.
Read more at Tulane University
Image: Salt marshes about 30 miles (50 km) southeast of New Orleans are vulnerable to drowning. (Credit: Photo by Torbjörn Törnqvist)
