A stark new study has concluded that New Orleans has reached a "point of no return" due to the climate crisis, with ongoing sea-level rise and rampant wetland erosion threatening to swallow the city within decades. The paper, published in Nature Sustainability, estimates that the cultural hotspot could be surrounded by the Gulf of Mexico before the end of this century.
Multiple Threats Facing Southern Louisiana
Low-lying southern Louisiana faces a combination of threats: rising sea levels driven by global heating, strengthening hurricanes, and gradual subsidence of a coastline carved apart by the oil and gas industry. The study compares today's rising temperatures to a similar warm period 125,000 years ago, which caused sea levels to rise significantly. Southern Louisiana is now facing 3-7 meters of sea-level rise and the loss of three-quarters of its remaining coastal wetlands, causing the shoreline to migrate as much as 100 kilometers (62 miles) inland, stranding New Orleans and Baton Rouge.
Immediate Action Required
The researchers describe the region as the "most physically vulnerable coastal zone in the world" and call for immediate action to prepare a smooth transition for people away from New Orleans, which has a population of about 360,000. Louisiana has already experienced population loss, and the trend will accelerate in a disordered way without action. "While climate mitigation should remain the first step to prevent the worst outcomes, coastal Louisiana has evidently already crossed the point of no return," the paper states.
Billions of dollars have been spent on levees, floodgates, and pumps after Hurricane Katrina in 2005, but the growing threats mean these defenses will not save the city in the long run. "In paleo-climate terms, New Orleans is gone; the question is how long it has," said Jesse Keenan, a climate adaptation expert at Tulane University and co-author of the paper. "Even if you stopped climate change today, New Orleans's days are still numbered. It will be surrounded by open water, and you can't keep an island situated below sea level afloat."
Relocation Planning Needed
City, state, and federal leaders should begin supporting a coordinated move away from the New Orleans region, starting with the most vulnerable communities, such as those in Plaquemines parish outside the levee system. "New Orleans is in a terminal condition, and we need to be clear with the patient that it is terminal," Keenan said. "There is an opportunity for palliative care, we can transition people and the economy." However, he noted that no politician wants to give this terminal diagnosis publicly.
A separate study released last week found that 99% of New Orleans's population is at major risk of severe flooding, the worst exposure of any US city. "Even compared to all other US cities, New Orleans really stands out, which is alarming," said Wanyun Shao, a geographer at the University of Alabama and co-author of that study. "There is no specific timeline to how long New Orleans has left but we know it's in big trouble."
Wetland Loss and Mitigation Efforts
Since the 1930s, Louisiana has lost 2,000 square miles of land to coastal erosion, equivalent to the size of Delaware, with another 3,000 square miles expected to vanish in the next 50 years. The rate of land loss is so rapid that a football pitch-sized area is wiped out every 100 minutes. To counter this, Louisiana had planned the Mid-Barataria Sediment Diversion project, which broke ground in 2023 to restore natural sediment flow. However, Governor Jeff Landry scrapped the project last year, citing its $3 billion cost and threats to the fishing industry.
Proponents, including former congressman Garret Graves, called it a "boneheaded decision" that would result in major setbacks for coastal protection. According to the new study, the loss of the sediment diversion plan "effectively means giving up on extensive portions of coastal Louisiana, including the New Orleans area." A legal effort to force oil and gas companies to pay for wetland damage is also in doubt after the US Supreme Court allowed the fossil fuel industry to contest a state jury decision.
Future Outlook
While the US has never wholesale moved a major city, numerous communities have relocated for economic or climate reasons. Keenan suggests the government could start planning infrastructure in safer areas north of Lake Pontchartrain. "This could be an opportunity for New Orleans to help migrate people further north, invest in long-term infrastructure and make that sustainable," he said. "That exodus has already begun, so if nothing is done, people will just trickle out over time and it will be an uncoordinated mess."
Timothy Dixon, an expert at the University of South Florida, noted that policymakers should have thought about relocation a century ago. "Governments may not have the ability to just command people to leave, but people will volunteer to move and we are seeing that already," he said. "I'm not optimistic our political system is capable of dealing with this stuff, it will take leadership and unpopular decisions."
