‘Point of no return’: New Orleans relocation must start now due to sea level, study finds. Louisiana’s cultural hotspot could be surrounded by Gulf of Mexico before end of this century, authors say

 

By Oliver Milman

 

The process of relocating people from New Orleans should start immediately, as the city has reached a “point of no return” that will see it surrounded by the ocean within decades due to the climate crisis, a stark new study has concluded.

Ongoing sea-level rise and the rampant erosion of wetlands in southern Louisiana will swallow up the New Orleans area within a few generations, with the new paper estimating the city “may well be surrounded by the Gulf of Mexico before the end of this century”.

Low-lying southern Louisiana faces multiple threats, with rising sea levels driven by global heating, compounded by strengthening hurricanes, also a feature of the climate crisis, and the gradual subsidence of a coastline that has been carved apart by the oil and gas industry.

 

Southern Louisiana is facing 3-7 metres of sea-level rise and the loss of three-quarters of its remaining coastal wetlands, which will cause the shoreline “to migrate as much as 100km (62 miles) inland”, thereby stranding New Orleans and Baton Rouge, according to the study, which compared today’s rising global temperatures with a period of similar heat 125,000 years ago that caused a rise in sea level.

This scenario makes the region the “most physically vulnerable coastal zone in the world”, the researchers state, and requires immediate action to prepare a smooth transition for people away from New Orleans, which has a population of about 360,000 people, to safer ground.

Louisiana has already experienced population loss in recent years, and this trend will accelerate in a disordered way, the paper warns, should no action be taken to confront the perils faced by its largest city and surrounding communities.

“While climate mitigation should remain the first step to prevent the worst outcomes, coastal Louisiana has evidently already crossed the point of no return,” added the perspectives paper, published in the Nature Sustainability journal. A perspectives paper is a scholarly article that provides an assessment, rather than new data.

Billions of dollars have been spent to fortify New Orleans with a vast network of levees, floodgates and pumps erected after 2005’s catastrophic Hurricane Katrina. But the growing threats to the city mean the levees, which already require hefty upgrades to remain sufficient, will not be able to save the city in the long run, the new paper warns.

 

“In paleo-climate terms, New Orleans is gone; the question is how long it has,” said Jesse Keenan, an expert in climate adaptation at Tulane University and one of the paper’s five co-authors.

 

Keenan said the timeframe available to plan a retreat isn’t certain but “it’s most likely decades rather than centuries”.

“Even if you stopped climate change today, New Orleans’s days are still numbered,” he added. “It will be surrounded by open water, and you can’t keep an island situated below sea level afloat. There’s no amount of money that can do that.”

City, state and federal leaders should begin work to help support people moving away from the New Orleans region in a coordinated way, starting with the most vulnerable communities, such as those in Plaquemines parish who live outside the levee system, Keenan said.

“New Orleans is in a terminal condition, and we need to be clear with the patient that it is terminal,” he said. “There is an opportunity for palliative care, we can transition people and the economy. We can get ahead of this.”

But, he added, “no politician wants to first give this terminal diagnosis. They will speak about it behind closed doors, but never in public.”

New Orleans faces obvious challenges – situated in a bowl-shaped basin below sea level, the city already has 99% of its population at major risk of severe flooding, the worst exposure of any US city according to a separate study released last week.

“Even compared to all other US cities, New Orleans really stands out, which is alarming,” said Wanyun Shao, a co-author of this study and a geographer at the University of Alabama.

“There is no specific timeline to how long New Orleans has left but we know it’s in big trouble. They are facing one of the highest sea level rises in the world and I don’t know how long human effort can fight against that tide. It’s like a timebomb.”

Shao said she concurred that relocation of people would have to take place. “I know it’s a politically and emotionally charged issue, there are people with a deep attachment to New Orleans,” she said. “But managed retreat, no matter how unappealing it may be, is the ultimate solution at some point.”

A major pressure upon this southern cultural hotspot is that its surrounding land is briskly receding. Since the 1930s, Louisiana has lost 2,000 sq miles of land to coastal erosion, equivalent to the size of Delaware, with a further 3,000 sq miles set to vanish over 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 help counter this, Louisiana last decade settled upon a new sort of plan that eschewed building yet more flood defenses and instead sought to harness the Mississippi River’s natural ability to rebuild land. Levees and other infrastructure have, until now, straitjacketed the naturally meandering Mississippi and pushed the sediment it carries straight into the Gulf of Mexico, rather than replenish the coastal wetlands.

The so-called Mid-Barataria Sediment Diversion project, which broke ground in 2023, would help restore a more natural flow in the Mississippi Delta and allow sediment to build up in coastal areas where it has been lost. More than 20 sq miles of new land would be created over the next 50 years under the plan, the project estimated.

However, Jeff Landry, Louisiana’s Republican governor, scrapped the project last year, arguing its $3bn cost was too high and that it threatened the state’s fishing industry. “This level of spending is unsustainable,” Landry said at the time, adding that the project imperiled the livelihoods of “people who have sustained our state for generations”.

Proponents of the project, which was funded via a settlement from BP over the Deepwater Horizon disaster in 2010, decried the decision as disastrous for the state, pointing out fishing communities will need to move anyway because of worsening erosion.

Garret Graves, a Republican former congressman who once led the state’s coastal restoration agency, said Landry was guilty of a “boneheaded decision” that would “result in one of the largest setbacks for our coast and the protection of our communities in decades”.

According to the new research paper, 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 damage to Louisiana’s coastline, meanwhile, is also in doubt. This month, the US supreme court allowed the fossil fuel industry to federally contest a state jury decision that Chevron pay $740m to remedy harm caused to wetlands by dredging canals, drilling wells and dumping wastewater.

“The combination of these decisions is driving a scenario where the state has stopped trying to build land,” Keenan said. “That just accelerates the timeline. They could be buying time, but that option is foreclosed now, meaning it’s a certainty the New Orleans levees will fail again multiple times. The flood water will have nowhere else to go.”

While the US has never wholesale moved a major city before, numerous communities have relocated for economic reasons in the past, with some now being shifted due to the climate crisis, too. In Louisiana, the government could start planning and building appropriate infrastructure in safer areas on the other side of Lake Pontchartrain, the large estuary that sits to the north of New Orleans, Keenan said.

“This could be an opportunity for New Orleans to help migrate people further north, invest in long-term infrastructure and make that sustainable,” Keenan 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. The market will speak as people won’t be able to get insurance. Louisiana has to stop the bleeding and acknowledge this is happening. But at the moment there is no plan.”

Timothy Dixon, an expert in coastal environments at the University of South Florida who was not involved in the new paper, said the study “does a nice job” of highlighting the challenge Louisiana faces with subsiding land combined with rising sea levels.

“New Orleans is not going to disappear in 10 years or anything like that, but policymakers really should’ve thought about a relocation plan a century ago,” said Dixon, whose own research has recommended a measured retreat from coastal Louisiana.

“Governments may not have the ability to just command people to leave, but people will volunteer to move and we are seeing that already. I’m not optimistic our political system is capable of dealing with this stuff, it will take leadership and unpopular decisions. Also, many people don’t want to move. They love where they are born.”

Landry’s office was contacted for comment but did not respond.

The sub-Arctic town pitching itself as Canada's gateway to Europe. "But again, let's remember that climate change is upon us," he noted. "What's the polar season going to look like in 10 years' time, or 20 years' time?"

 

Churchill mayor Mike Spence is hoping his town's port can serve as a hub for shorter shipping from Canada to Europe 

by  Nadine YousifSenior Canada reporter, Churchill, Manitoba 

 

The Port of Churchill sits idle for most of the year, blanketed by snow and frozen by the bitter cold climate of Canada's sub-Arctic. It's only operational in the summer for four months, sometimes five.

But where weather is a hindrance, it has geography on its side - the northern Manitoba port sits on the Hudson Bay, a vast body of water with a direct route through the Bay's strait into the Labrador Sea and the north Atlantic Ocean.

From there, cargo ships sail more quickly to Europe, and can reach Africa and South America, delivering goods ranging from food to critical minerals, and even – Canada's leaders hope – liquified natural gas (LNG).

For decades, ambitions of expanding the Port of Churchill have fallen short — derailed, locals argue, under years of poor management as experts openly questioned whether an Arctic port makes good economic sense. Canada is now hoping to change that, guided by the inevitability of climate change, the challenge of US tariffs, and Europe's energy shortage fuelled by ongoing global conflicts.

"Canada has an abundance of resources, and this port expansion will mean we can ship more to the world," Prime Minister Mark Carney said earlier this year.

The expansion of the Port of Churchill has been flagged as a key project by Carney that has the potential to transform Canada's economy and reduce its trade reliance on the US, working towards the prime minister's goal of doubling non-US exports in the next decade.

To outsiders, Churchill is known as the Polar Bear Capital of the World. Its economy has long relied on seasonal tourism, with visitors flocking to the town in the late summer and autumn to catch a glimpse of the northern lights and local wildlife like beluga whales, caribou and — as its moniker suggests — polar bears.

But it is also the site of Canada's only Arctic deep-water seaport, meaning it has the potential to accommodate ultra-large container vessels, oil tankers and LNG ships. With rail access to Churchill through southern Manitoba, the town has a direct travel path to resource-rich western Canada.

Because of Churchill's frigid sub-Arctic temperatures, the port is currently operational for only about four to five months a year 

The Port of Churchill opened nearly a century ago and was primarily used to export grain from the prairies. That ended in 2016, as shipments declined with producers opting for cheaper routes. It reopened in 2019, when it began shipping grain again as well as key supplies to other parts of northern Canada.

For Churchill, a remote town of approximately 1,000 residents, developing the port is seen as an opportunity to create hundreds of jobs and improve quality of life.

The port had fallen into disrepair under a Denver-based company that took ownership of it in 1997, said Mike Spence, the mayor of Churchill and co-chairman of the Arctic Gateway Group, a consortium of indigenous and community groups that now own the port.

Spence said the group wanted "to take control of our own destiny". The ownership transfer was finalised in 2018.

Since then, Ottawa has spent C$320m ($235m; £174m) on the port, including on its maintenance and restoration.

"The previous owner didn't invest in the port, in the rail line," Spence told the BBC, speaking inside a small restaurant attached to a hotel that he co-owns in Churchill — one of the few that stays open in the off-season winter months.

Work has since been done to modernise the railway and the port's infrastructure. In August 2024, the port delivered its first critical mineral shipment ever to Belgium.

It is now funding studies to see if it can be economically viable year-round, and if so, become a hub that would be capable of delivering resources to Europe. The port has also been pitched as a way for Canada to strengthen its Arctic sovereignty.

Manitoba Premier Wab Kinew said the goal is to start shipping out gas from the Port of Churchill by 2030 - a timeline dismissed by his political opponents as a "complete fabrication".

Alex Crawford, an assistant professor and researcher of Arctic climate systems at the University of Manitoba, is part of a team that was tapped by Arctic Gateway Group to study open water shipping in the region.

"Ice-free shipping year-round is not going to happen this century, even with a really aggressive warming scenario," he said.

He told the BBC that navigating Canada's Arctic waters is a complicated task because ice forms inconsistently along the Hudson Bay, making it difficult for ships to travel through for most of the year without an escort of costly icebreakers.

Icebreakers have been used by Russia in recent years to export natural gas and minerals year-round from Siberia to Asia through the Northern Sea Route. The vessels, which are nuclear-powered, have been dubbed "the world's largest and most powerful" by the US Naval Institute.

Canada's icebreaker fleet is much smaller by comparison, and plans to build new ships have been derailed over decades by bureaucracy and limited resources.

 In recent years, Canada launched a plan to build a new fleet, including a class 2 icebreaker that can operate year-round and cut through ice as tall as 10ft. It is this type of advanced icebreaker that would make navigating through the frozen Hudson Bay possible, Crawford said.

 

There are also questions on whether a port expansion would jeopardise the local wildlife and with it, the valuable tourism industry.

Mayor Spence said that concern will be part of ongoing engagement with the local community.

"But again, let's remember that climate change is upon us," he noted. "What's the polar season going to look like in 10 years' time, or 20 years' time?"

He added that people in the region want employment. "The trick here is to find a balance."

Others are skeptical about just how much economic potential the Port of Churchill can unlock, especially if it is not operating year-round.

Ecotourism is Churchill, Manitoba's largest industry, as visitors flock to the town in the summer months to catch a glimpse of polar bears and the northern lights

"From a standard maritime shipping perspective, it does not make much sense unfortunately," said Jean-Paul Rodrigue, a professor of Maritime Business Administration at Texas A&M University in Galveston.

Rodrigue noted that navigating Arctic waters in and of itself is expensive because ships need to be especially equipped for the harsher conditions. He added that demand for LNG is typically constant, meaning the port would need to operate 12 months of the year.

Businesses, he said, will need to consider whether it's worth the extra costs to shorten travel by just a few days.

He noted that the Port of Churchill has long been "a symbol of Canadian Arctic maritime ambitions".

Those ambitions, he argued, have not been realised because the project has failed to deliver a clear business case in the past.

While the Port of Churchill's development has been flagged as a focus area for Prime Minister Carney's economic growth plans, it is not on the shortlist of projects due to receive more immediate federal government support, signalling its expansion is not yet a sure thing.

But Rodrigue is not entirely pessimistic. He said the port could serve a niche, particularly for stockpiling and delivering strategic minerals mined in western Canada.

Canada now finds itself at an "inflection point", he said, which could transform the way businesses and the public view the port.

Here’s some good news for a change. In 2025 tropical deforestation fell by more than a third after reaching record levels the previous year.

 

Data from the Drivers of Tropical Forest Loss (2008 to 2019) Geo-Wiki Campaign

 

 By Fabiano Maisonnave

 Experts welcomed the data with hope — and caution. Tropical forest loss is still 46% higher than ten years ago. Today’s newsletter looks at how Brazil’s 2023 anti-deforestation plan is starting to bear fruit. We also bring you the latest on how climate change impacted Europe’s temperatures, glaciers and oceans last year.

  

Deforestation win

 

Tropical forest loss declined significantly last year, falling 36% after reaching a record level in 2024. Still, the world lost 4.3 million hectares (10.6 million acres) of rainforest — an area roughly the size of Denmark, or more than 11 soccer fields every minute.

New data from the University of Maryland, published through the World Resources Institute’s Global Forest Watch, shows that the loss of primary — or mature and largely undisturbed — humid tropical forests slowed down in 2025. But it was still 46% higher than a decade earlier, and last year saw a relative lull in wildfires after an exceptionally bad fire year in 2024. Blazes are increasing in the tropics due to warmer temperatures and more severe droughts

 

Outside the tropics, the climate signal was starker. Wildfires burned 5.3 million hectares in Canada, making 2025 the country’s second-worst fire year on record. In France, fire-driven tree-cover loss was the most severe on record, seven times higher than in the previous year. 

The analysis uses a broad definition of forest loss that includes not just deforestation for agriculture but also timber harvesting and natural disturbances to forests. 

At the COP26 climate summit in 2021, more than 100 countries pledged to halt and reverse forest loss by 2030. The world remains far from that goal as agricultural expansion and fires continue to destroy important biodiversity hotspots and carbon sinks. Forest loss in 2025 was still about 70% too high for countries to be on track for the deadline, according to the World Resources Institute, or WRI.

“Achieving this goal in the coming years will not be easy as forests become more vulnerable to climate change, and as humanity’s demand for food, fuel and materials from forests and the lands they stand on continues to grow,” said Elizabeth Goldman, co-director of Global Forest Watch at WRI.

Smoke rises during a fire in the Brazilian Amazon

Photographer: Leonardo Carrato/Bloomberg

 

 

Brazil, which encompasses two-thirds of the Amazon, the world’s largest rainforest, recorded the largest absolute area of primary forest loss. But it cut that loss by 42% from the previous year. The report attributes the decline to stronger environmental policy and enforcement under President Luiz Inácio Lula da Silva.

The improvement stands in stark contrast to 2024, when Brazil’s Amazon suffered its worst drought on record, fueling unprecedented forest fires.

André Lima, Brazil’s secretary for deforestation control, said in a phone interview that the country’s forest policy rests on “two agendas that are intertwined” — curbing deforestation and controlling fires. He said the government relaunched the federal anti-deforestation plan in 2023 under Lula and is now beginning to see results. Citing Brazil’s official data, Lima said Amazon deforestation fell 50% in 2025 compared with 2022.

Tokyo workers asked to swap suits for shorts to combat energy costs and heat

 

People on the Shibuya crossroad during an intense Tokyo heatwave in June last year. Photograph: Anadolu/Getty Images

by Justin McCurry in Tokyo

 

Public servants working for the Tokyo metropolitan government are being encouraged to swap their suits for shorts this summer to combat sweltering heat and rising energy costs caused by the US-Israel war on Iran.

Inspired by the country’s Cool Biz energy-saving initiative, Tokyo officials hope the measure will cut dependence on air conditioning.

Cool Biz, launched by the environment ministry in 2005, initially encouraged bureaucrats to dispense with ties and jackets, but has so far stopped short of allowing them to display their bare legs in front of colleagues.

Japan and other countries in Asia are growing anxious about the economic effects of the conflict in the Middle East, amid rising oil prices and shortages of petroleum products such as jet fuel.

 

Resource-poor Japan is particularly vulnerable to a prolonged war as it depends on the Middle East for 90% of its oil imports, most of which pass through the strait of Hormuz. About 20% of the natural gas used in South Korea comes via the same route.

Vietnam, South Korea and other countries have taken steps to ration energy use, while other Asian nations have encouraged government officials to work from home or reduced the length of the working week. In Seoul, authorities have urged residents to make short trips on foot or by bicycle.

 

Japan has already tapped into its large strategic oil reserves, with local media reporting on Friday that it plans to release a further 20 days’ worth from 1 May. It is also sourcing oil imports from suppliers that do not use the strait of Hormuz.

Experts have warned that if shipping in the vital waterway doesn’t return to normal soon, the world’s fourth-biggest economy will eventually face a crude oil shortage. That could force businesses and households to make more drastic cuts in petrol and electricity usage reminiscent of those introduced during the oil shocks of the 1970s.

The threat of an energy crunch had been “one of the factors” in allowing Tokyo government staff to wear casual clothes to work, Agence France-Presse said, adding that some employees had been spotted in shorts, T-shirts and short-sleeved blouses since the initiative’s launch this week to coincide with the start of Japan’s heatstroke warning system.

“I was a bit nervous, but it’s very comfortable, and I feel like it’ll improve my work efficiency,” a metropolitan government official who was wearing shorts to the office for the first time told the Yomiuri Shimbun newspaper. “As it gets even hotter, I’d like to come in earlier and work from home as well.”

Citing “a severe outlook for electricity supply and demand,” Tokyo’s governor, Yuriko Koike, who as environment minister was behind the Cool Biz campaign two decades ago, told reporters: “We encourage cool attire that prioritises comfort, including polo shirts, T-shirts and sneakers and – depending on job responsibilities – shorts”.

War notwithstanding, Japanese employers have been forced to rethink old rules on workplace attire as a result of the climate crisis. Last year, the country endured its hottest summer since records began in 1898, according to the meteorological agency.

Now that it is no longer unheard of for temperatures to rise to 40C or above, the agency last week announced a new extreme weather event: kokusho, or “cruelly hot”.

After 1,200 years, cherry blossom record to live on despite Japanese scientist’s death. Prof Yasuyuki Aono’s meticulous work charted shifting bloom dates as a marker of climate change

 

People viewing cherry blossoms in Osaka last week. Photograph: Jiji Press/EPA

by  Chris Baraniuk

 

Even in his final months, he counted the days until the cherry blossoms. Prof Yasuyuki Aono of Osaka Metropolitan University spent his career gathering data on the spring flowering dates of cherry trees in Japan in what is one of the world’s longest climate records tracking a seasonal occurrence.

Using sources dating as far back as the 9th century, he revealed that cherry tree flowerings have occurred progressively earlier in recent decades – a now famous marker of climate change.

 

Last April, Aono posted a photo to social media of his spreadsheet. He had just completed the 2025 entry, recording “4 [April]” as the peak flowering date for the particular cherry tree species he tracked, the mountain cherry, or Prunus jamasakura.

Below this, the next row was already marked “2026” but Aono never got to fill it in. He died on 5 August last year, according to former colleagues contacted by the Guardian.

Yasuyuki Aono learned old forms of Japanese so he could read 9th-century records. Photograph: Richard Primack

“You can very much see that he planned to continue,” said Tuna Acisu, a data scientist at Our World in Data, an online platform that publishes a chart based on Aono’s cherry tree data. “That made me a little bit emotional.”

Now, following a search launched by Acisu last week – sparked by fears that no one would be able to continue the 1,200-year cherry blossom record – a researcher in Japan has stepped forward and offered to make formal observations of the mountain cherry’s spring flowerings.

“He is consulting the same sources as Prof Aono to get us this year’s cherry blossom peak bloom and said he will confirm the date in the coming days,” Acisu said. The researcher in question asked to remain anonymous until the arrangement is finalised.

Acisu and colleagues first realised that something may have happened to Aono when they noticed in January that his university web page was no longer active. They then learned that he had died and that no other researcher or institution had emerged to carry on his observations. Spring arrived with no new mountain cherry data.

After Acisu launched her campaign to find a new cherry blossom observer, she received dozens of messages. “It’s really great to know that the dataset is being continued,” she said, expressing her gratitude to the new researcher. “I feel very relieved.”

 

Crucially, Acisu had sought a contact in Japan who could continue tracking not only the same species of cherry, but also in the same location: Arashiyama, Kyoto.

There are other projects that monitor cherry tree flowerings around Japan, since cherry bloom festivals are an important part of culture and tourism in the country, but not this specific species. For example, the Japan Weather Association monitors a different species: the Somei-yoshino cherry (Prunus x yedoensis), which was cultivated in the 19th century.

 

That Aono was able to compile flowering data for the mountain cherry over a period spanning more than 1,200 years is what gave his data series such significance, said Acisu.

Scientists have found the signature of climate change in a wide variety of other sources, including tree rings, plant pigments deposited in seabed sediments, and even temperature and humidity records jotted down by organ tuners in British churches.

Among the revelations made by Aono were the 2021 and 2023 peak flowering dates – they are the earliest in the entire mountain cherry record, occurring on the 85th and 84th day of those years, respectively.

Aono’s work on the mountain cherry was “extremely important”, said Toshio Katsuki, a dendrologist at the Forestry and Forest Products Research Institute in Ibaraki prefecture, who added that efforts to continue recording the same species’ spring flowering dates would be academically valuable.

Tourists wearing kimonos pose with cherry blossoms in Kyoto at the end of March this year. Photograph: Manami Yamada/Reuters

Richard Primack, a professor of biology at Boston University, met Aono on a trip to Japan in 2006. Aono told him that he had learned to read old forms of Japanese in order to build up his dataset of mountain cherry flowering dates. In dusty historical archives, Aono would find references to cherry blossom festivals in Kyoto and, from that, was able to calculate the flowering dates for specific years.

While some years are missing, the earliest record he found dated to 812. “It was really quite an amazing experience,” said Primack, remembering the meeting. “You just realise how dedicated an individual he was.”

In a paper published earlier this month, Primack and Katsuki described how flowering of the Somei-yoshino cherry also appears to be affected by climate change in southern areas of Japan. Data from 1965 to 2024 shows that milder winters were increasingly causing the spring-flowering cherries to have “a kind of bedraggled look, rather than a full, dazzling display,” said Primack. “Many of the flower buds were falling off without opening.”

Quiet adapting - Climate change is a verboten topic in the Trump administration. But that hasn’t stopped the US military from continuing to prepare for it.

 

Tyndall is being rebuilt as a super-resilient “installation of the future.”

Photographer: Patrick Focke/US Department of Defense via Digital

 

 By Amanda Kolson Hurley

 

 

When Hurricane Michael, a Category 5 storm, tore through Florida’s Tyndall Air Force Base in 2018, it battered F-22 stealth fighter jets, destroyed hundreds of buildings and churned up 700,000 cubic yards of debris. The total cost of the damage approached $5 billion.

Now, Tyndall is being rebuilt as a super-resilient “installation of the future.” New buildings sit more than a foot above the ground, to remain dry through 75 years of sea-level rise. Their roofs are designed to withstand winds of up to 165 miles per hour. Manmade oyster reefs will protect coasts by breaking up waves.

The massive project will be 70% complete next year, said the officer leading it, Col. Robert Bartlow, chief of the US Air Force Civil Engineer Center Natural Disaster Recovery Division. “This is a first for the Air Force,” he said, with large-scale, cutting-edge construction taking place “on top of an existing base, while there was a continued flying mission.”

 

Storms like Michael are becoming more powerful and damaging as the world warms, and many military installations are exposed to them and other climate hazards. Still, Secretary of Defense Pete Hegseth vowed last year that the Pentagon wouldn’t do any “climate change crap” on his watch. Biden-era climate action plans were scrapped, and the 2025 National Security Strategy invoked climate change only to label it a “disastrous” ideology. Hegseth canceled nearly 100 research studies related to global warming and security, which experts say will compound the loss of climate knowledge across the federal government under President Donald Trump.

“Because ‘climate’ is a dirty word, we’re not investing in that predictive capability,” said Sherri Goodman, secretary general of the non-governmental International Military Council on Climate and Security and, from 1993 to 2001, the US deputy undersecretary of defense for environmental security.

But as Tyndall shows, the Defense Department is still engaged on one front of the climate fight: steeling its bases against the effects of a warming atmosphere, such as higher seas, fiercer storms and deadlier fires. A new flood wall is rising at the US Naval Academy in Maryland; a low-lying Air Force runway is being elevated in Virginia; and projects are underway to reduce wildfire risk around various military sites in Hawaii.

Work that was previously described as confronting the climate threat is now touted for ensuring “resilience” and “readiness.” The semantics are a nod to necessity: At stake are hundreds of billions of dollars of assets and the ability to launch missions quickly and smoothly.

Much of the military’s resilience work began years ago; construction timelines are long. The $900 billion 2026 National Defense Authorization Act, which Trump signed into law in December, includes measures that could be said to come under the umbrella of climate adaptation. The law bolsters the military’s ability to respond to wildfires; raises the cost limit for replacing structures destroyed by disasters; and requires military leaders to identify the biggest risks to water security on bases.

Close to $400 billion of federal government assets, most of them belonging to the Defense Department, are at high risk of being hit by a major coastal flood or storm in coming years, according to a Bloomberg Law analysis.

The Pentagon explicitly recognized the warming climate as a danger for many years. The 2008 National Defense Strategy flagged climate change as an emerging risk, and two years later it was named a national security threat in the Pentagon’s Quadrennial Defense Review. After that, the Defense Department and the individual armed forces put out a stream of climate and sustainability plans. (Some have now been removed from government websites.)

James Mattis, who served as defense secretary during President Donald Trump’s first term, described climate change as a destabilizing force in 2017. His Biden-era successor Lloyd Austin said in 2021, “We face all kinds of threats in our line of work, but few of them truly deserve to be called existential. The climate crisis does.”

Trump and Hegseth have made a sharp pivot. In a March 2025 memo to military leaders, Hegseth called climate change a “distraction” from fighting wars, ordered that references to it be removed from mission statements and barred any environmental initiatives from being included in the Future Years Defense Program, a strategic plan.

Hegseth also included a caveat big enough to steer an aircraft carrier through. “Nothing in this memorandum,” he wrote, “shall be construed to prevent the department from assessing weather-related impacts on operations, mitigating weather-related risks, conducting environmental assessments, as appropriate, and improving the resilience of military installations.”

The overarching goal at Tyndall, Bartlow said, is “preserving lethality in a high-end combat capability. When we talk about resilience, it’s focused on preserving that combat capability.” If another Category 5 hurricane hits, “there’ll be some interruptions, but the idea is you’ll be able to recover this installation quickly,” hesaid. “You can make that direct link back to readiness.”

Critical Atlantic current significantly more likely to collapse than thought. Scientists say finding is ‘very concerning’ as collapse would be catastrophic for Europe, Africa and the Americas

The Atlantic meridional overturning circulation is a major part of global climate system and is known to be at its weakest for 1,600 years as a result of climate crisis. Photograph: Henrik Egede-Lassen/Zoomedia/PA

by  Damian Carrington Environment editor

 

The critical Atlantic current system appears significantly more likely to collapse than previously thought after new research found that climate models predicting the biggest slowdown are the most realistic. Scientists called the new finding “very concerning” as a collapse would have catastrophic consequences for Europe, Africa and the Americas.

The Atlantic meridional overturning circulation (Amoc) is a major part of the global climate system and was already known to be at its weakest for 1,600 years as a result of the climate crisis. Scientists spotted warning signs of a tipping point in 2021 and know that the Amoc has collapsed in the Earth’s past.

Climate scientists use dozens of different computer models to assess the future climate. However, for the complex Amoc system, these produce widely varying results, ranging from some that indicate no further slowdown by 2100 to those suggesting a huge deceleration of about 65%, even when carbon emissions from fossil fuel burning are gradually cut to net zero.

 

The research combined real-world ocean observations with the models to determine the most reliable, and this hugely reduced the spread of uncertainty. They found an estimated slowdown of 42% to 58% in 2100, a level almost certain to end in collapse.

The Amoc is a major part of the global climate system and brings sun-warmed tropical water to Europe and the Arctic, where it cools and sinks to form a deep return current. A collapse would shift the tropical rainfall belt on which many millions of people rely to grow their food, plunge western Europe into extreme cold winters and summer droughts, and add 50-100cm to already rising sea levels around the Atlantic.

Dr Valentin Portmann, at the Inria Centre de recherche Bordeaux Sud-Ouest in France and who led the new research, said: “We found that the Amoc is going to decline more than expected compared to the average of all climate models. This means we have an Amoc that is closer to a tipping point.”

Prof Stefan Rahmstorf, at the Potsdam Institute for Climate Impact Research in Germany, said: “This is an important and very concerning result. It shows that the ‘pessimistic’ models, which show a strong weakening of the Amoc by 2100, are, unfortunately, the realistic ones, in that they agree better with observational data.”

He added: “I now am increasingly worried that we may well pass that Amoc shutdown tipping point, where it becomes inevitable, in the middle of this century, which is quite close.”

Rahmstorf, who has studied the Amoc for 35 years, has said a collapse must be avoided “at all costs”. “I argued this when we thought the chance of an Amoc shutdown was maybe 5%, and even then we were saying that risk is too high, given the massive impacts. Now it looks like it’s more than 50%. The most dramatic and drastic climate changes we see in the last 100,000 years of Earth history have been when the Amoc switched to a different state.”

 

The Amoc is slowing because air temperatures are rising rapidly in the Arctic because of global heating. That means the ocean cools more slowly there. Warmer water is less dense and therefore sinks into the depths more slowly. This slowing allows more rainfall to accumulate in the salty surface waters, also making it less dense, and further slowing the sinking and forming an Amoc feedback loop.

The Amoc system is highly complex and subject to random natural variations, making precise predictions impossible. However, a major weakening is now expected by scientists and that alone could have serious impacts in the decades to come.

The new research, published in the journal Science Advances, explored four different ways of using real-world observations to assess the models. They found a method called ridge regression, which had been little used in climate science before now, provided the best results.

The Amoc is difficult to model because it is governed by subtle differences in water density caused by salinity changes over the entire Atlantic. The reduction in uncertainty in the new analysis results from identifying the models that better reflect surface salinity in the south Atlantic, which scientists already knew was important. This makes the work “very credible”, said Rahmstorf.

Rahmstorf said Amoc slowdown in 2100 may be even greater than in the new, pessimistic assessment. This is because the computer models do not include the meltwater from the Greenland ice cap that is also freshening the ocean waters: “That is one additional factor that means the reality is probably still worse.”