Rising sea levels are threatening the western side of Louisiana’s coast, according to a Tulane study.

Co-author Torbjorn Tornqvist says they used data from the Coastal Restoration and Protection Authority to determine how fast the sea level is rising.

“This rate, on average, is about half an inch per year. That is almost exactly four times higher than the average rate that we see around the world,” Tornqvist said.

Tornqvist says the reason the rate is so high in Louisiana is the coast is sinking. He says in some parts of the Mississippi River delta, sediment accumulation keeps up with the rising sea. But he says accretion is not occurring as quickly on the west side of the coast.

“If we move to the Cheniere plain, which is basically southwest Louisiana, the situation there is really dire. There’s actually very few sites that are keeping up with the present rate of sea level rise,” Tornqvist said.

Tornqvist says if nothing is done, more than 60-percent of the sites they track in the westernmost coast will go under water. He says significant coastal restoration is the only hope. But he says even those efforts might not be enough.

“The rate of sea level rise is going to increase in the future. That is a near certainty because of climate change. So the conditions now are very challenging, but they’re going to be even worse in the future,” Tornqvist said.