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“Not If, But When Louisiana Wetlands Will Vanish, Study Says”

“‘We're screwed': The only question is how quickly Louisiana wetlands will vanish, study says “

“Because of increasing rates of sea level rise fueled by global warming, the remaining 5,800 square miles of Louisiana’s coastal wetlands in the Mississippi River delta will disappear. The only question is how quickly it will happen, says a new peer-reviewed study published Friday in Science Advances.

“This is a major threat not only to one of the ecologically richest environments of the United States but also for the 1.2 million inhabitants and associated economic assets that are surrounded by Mississippi Delta marshland,” the report concludes.

The new study reviewed the rates of sea-level rise that caused wetlands to disappear along Louisiana’s coast during the 8,500-year history of the current Mississippi River delta. It found that at rates of relative sea level rise — the combination of rising water and ground subsidence — of between 6 and 9 millimeters a year , ancient coastal marshes would turn into open water within 50 years. At rates of 3 millimeters a year, it would take a few centuries.

The globally averaged rate of sea-level rise between 2006 and 2015 was about 3.58 millimeters a year, and that doesn’t include local subsidence rates along Louisiana’s coast. As a result, the state’s wetlands already have exceeded a tipping point, the study’s authors say.”

Mark Schleifstein reports for the New Orleans Times-Picayune May 23, 2020.


“Loss of Louisiana Marshes That Protect New Orleans Is ‘Probably Inevitable,’ Study Finds” (Washington Post)