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Battery startup EnerVenue is planning an iconoclastic comeback. After failed plans to build a U.S. factory for its NASA-inspired tech, the firm announced $300 million in fresh funding to execute a manufacturing strategy that flies in the face of broader trends in the American battery market.
Battery startup EnerVenue is planning an iconoclastic comeback. After failed plans to build a U.S. factory for its NASA-inspired tech, the firm announced $300 million in fresh funding to execute a manufacturing strategy that flies in the face of broader trends in the American battery market.
A rendering shows how EnerVenue’s nickel-hydrogen batteries could be stacked in a warehouse, capitalizing on the chemistry’s safety, compared with lithium-ion’s. (EnerVenue)
EnerVenue seeks to commercialize a version of the pressurized nickel-hydrogen energy storage system that NASA used on the International Space Station and the Hubble Space Telescope. The original technology cost far too much to succeed in civilian power markets, but EnerVenue’s founders claimed to have swapped the platinum catalyst for a much cheaper material. The company says its battery can run 30,000 cycles with minimal degradation, maintaining its usefulness far beyond the typical lithium-ion battery’s shelf life, and with much better fire safety.
The Silicon Valley–based startup raised a $12 million seed round in 2020 and a $100 million Series A in 2021 from the likes of Saudi Aramco Energy Ventures and Schlumberger New Energy. In 2023, EnerVenue told Canary Media it would invest $264 million to open a factory in Kentucky and produce batteries by the end of the year.
Battery factories have been opening across the U.S. to meet skyrocketing demand for grid storage. Federal incentives reward factories for manufacturing batteries domestically and storage developers for installing batteries, as long as they don’t depend too much on “foreign entities of concern,” which in practical terms restricts corporate and supply chain exposure to China. This onshoring effort has moved so swiftly that the U.S. may well become self-sufficient in both battery cells and finished battery enclosures for grid storage by the end of this year.
EnerVenue opted not to contribute to this achievement, at least not anytime soon. The company pulled out of its Kentucky deal in 2024. The $300 million it unveiled March 31 (technically an extension of a $308 million Series B from 2024) will instead fund a factory buildout in Changzhou, China, which the company’s press release hailed as “the world’s epicenter of battery manufacturing expertise.” EnerVenue also promised to “expand its commercial operations across Asia, the Middle East, and Europe.”
“We see ourselves still as an American company,” Henning Rath, who took over as CEO in March, told Canary Media. But, he continued, “We’re going to become a global player.”
Why would this startup choose to zig to China when the rest of its peers are zagging to the U.S.?
For starters, once work began on the Kentucky factory, the company realized that its second-generation battery design wasn’t ready for mass production, and that it would be particularly capital-intensive to build a first-of-its-kind battery factory at the site, Rath said.
From the outside, it might seem sensible to design a viable product before starting to build a factory to mass-produce it. The venture-backed cleantech industry, however, boasts a long history of constructing factories for inventions that failed to function in either practical or commercial terms. Chalk it up to undue optimism, or the pressure to show venture investors a quicker path to mass production and revenue.
In any case, EnerVenue pulled the rip cord, and then-CEO Jorg Heinemann left in November 2024, spending 10 months as a “Cyclist, surf coach & c-suite advisor,” according to his LinkedIn, before becoming president and chief operating officer of a startup selling clean, dispatchable power to data centers. “As the company decided on shifting gears and we evaluated the technology and manufacturing setup, I think that both parties agreed to look into different options” Rath said of Heinemann’s departure. Rath didn’t formally step in as CEO until March; he previously ran supply chains for German residential solar startup Enpal — a task that involved sourcing Chinese solar products for installation back in Europe.
After the reset, EnerVenue delved back into engineering and spent nearly two more years honing a fourth generation of its tech, Rath said. Then the company made the choice to assemble the factory process in China, to take advantage of the mature battery manufacturing sector there.
EnerVenue now has a small R&D manufacturing line operating in Changzhou and is working to finish a 250-megawatt-hour-per-year line by the early fourth quarter of this year. The plan is to grow the factory to 1 gigawatt-hour in 2027 — a level of production that unlocks competitive unit economics, Rath said, at which point EnerVenue could “copy-paste it to different markets.” EnerVenue may have an easier time doing this than conventional battery upstarts, since the ingredients to make its nickel-hydrogen battery are more readily available around the world than the carefully refined cathode and anode materials in lithium-ion batteries.
“We have to showcase scale first, in a very capital-efficient way,” Rath said. “That is the reason why we chose China to build the first scale-up.”
That low-cost manufacturing environment comes with trade-offs, however.
The need to distance America’s energy system from China has become a rare point of agreement across the U.S. political divide. The Biden administration pursued this with tax incentives for companies that build batteries in the U.S. and those that install domestically produced batteries. The Trump administration kept those policies but added the more punitive “foreign entities of concern” test to withhold credits from companies subject to corporate control from China and from projects that use too much equipment from China.
Chinese companies that built factories in America have had to divest from those enterprises to preserve tax credit eligibility for the products made within. EnerVenue poses a different accounting challenge: Can an ostensibly American company move production to China and still sell batteries to the U.S. market that let project developers qualify for the tax credits? Will that ability persist after EnerVenue’s latest fundraise welcomed significant equity investment from the Hong Kong Investment Corp. (wholly owned by the government of Hong Kong) and the Hong Kong–based family office of real estate tycoon Peter Lee?
On maintaining tax credit eligibility for the China-built batteries, Rath said, “We haven’t had a clear conclusion on this yet, but I think within the next probably two months or so, we will have certainty and execute against it.”
Geopolitical intrigue is just one of the challenges EnerVenue faces in commercializing a novel battery. Also on the list: Convincing buyers to bet on a little known chemistry for large-scale grid projects, and to embrace the whole new style of power plant unlocked by a battery with a vastly different operating profile than ubiquitous lithium-ion systems.
Typically, the startups vying to replace lithium bill their inventions as long-duration storage, capable of cheaply shifting clean energy production for many more hours than the four or five that lithium-ion batteries currently muster. Companies like Form Energy and Noon Energy are attempting to push the boundaries to 100 hours. EnerVenue does not stake such claims, and to the extent that the company touts duration, it’s in the different context of the batteries’ overall operating life. Rath said customers have asked for different configurations — from a 2-hour duration up to a 25-hour duration — but didn’t highlight a particular level as indicative of what the technology can do.
Instead, EnerVenue hopes to attract customers with its batteries’ ability to discharge three times a day for 30 years without eroding efficiency or catching fire, and operating parameters from minus 4 to 140 degrees Fahrenheit. (Lithium-ion grid batteries typically discharge once or twice a day and can tolerate a much narrower band of temperatures.) That could make EnerVenue’s system ideal for utilities in rugged environments or petrochemical complexes worried about battery safety. The many cycles a day, meanwhile, could help developers in volatile energy markets who want to take advantage of alternating periods of super-low and super-high pricing.
The trade-off of this impressive cycle life is that the battery needs to cycle a lot to justify its up-front costs. Doing so would require a very different sort of battery business model than what’s in practice today. After EnerVenue shows it can manufacture a working battery, it’ll have to prove that customers are actually willing to pay that premium.
A bill advancing through California’s legislature would create pathways for virtual power plants to compete with fossil-fueled peaker plants — a move that could help the state curb its fast-rising utility rates.
Virtual power plants are aggregations of small-scale batteries, electric vehicles, smart thermostats, and other customer-owned devices that can be called upon to provide cheap capacity to the grid. VPP programs already exist in California, but the state’s utility and grid regulatory structures don’t offer a clear way for VPPs to replace peaker plants.
Senate Bill 913, introduced by state Sen. Josh Becker, a Democrat, would allow VPPs to “compete on a level playing field with traditional power sources to provide grid reliability at the lowest cost.” The bill, which lays out a slew of policy changes, passed out of the California Senate Energy, Utilities, and Communications Committee earlier this month, a first step on the way to a potential vote before the full state Senate and Assembly.
Gas-fired peaker plants are a major driver of California’s rising electricity bills. Most of the state’s aging peaker plants are used only during a handful of hours each year when electricity demand is particularly high, but utility customers are required to pay for them to be available year-round in case of emergency.
VPPs can accomplish this job at a much lower cost, their advocates say, because customers have already paid to install these devices in their homes and businesses. The potential is vast: Millions of homes across California have devices that can turn down power use, and hundreds of thousands have batteries that can inject power onto the grid — all of which can be used to reduce the need for those “peaker” power plants.
Still, SB 913 may face an uphill climb, even in California’s Democratic-controlled government.
Pacific Gas & Electric, Southern California Edison, and San Diego Gas & Electric, the state’s major utilities, haven’t openly opposed the legislation. But VPP advocates say the utilities have quietly pushed back against programs that might undermine their ability to invest in — and earn guaranteed profits on — grid infrastructure to serve peak electricity demand.
The California Public Utilities Commission, whose five members have all been appointed by Democratic Gov. Gavin Newsom, has taken a number of actions in recent years that have reduced the ability of customer-owned resources to serve grid needs. Newsom also vetoed a slate of pro-VPP legislation last year.
But Becker and SB 913’s supporters are hopeful that mounting concerns about energy affordability could push the VPP legislation over the finish line this year. The bill is backed by clean energy companies, environmental groups, and consumer advocates.
“This is part of a nationwide effort that you’re starting to see, which is all about making better use of the clean energy resources that people already have in their homes to both lower cost and to improve reliability and to reduce pollution,” Becker, who’s authored several utility cost-containment and VPP bills in the past few years, told Canary Media. “I’m hopeful that now that more and more folks are focused on these things, we can move the ball forward.”
At its core, SB 913 is aimed at answering a fundamental question: How can VPPs reduce our reliance on gas-fired power plants that rarely ever run?
In California, the state’s aging peaker plants are paid to be available through a program called resource adequacy. In recent years, resource adequacy has become an increasingly larger part of customers’ bills, according to the community energy providers that are having to pay higher and higher prices to secure it.
The state’s growing fleet of utility-scale batteries is starting to become available for resource adequacy, but storage can’t meet these requirements on its own. For now, aging gas power plants remain the primary last resort for this critical service, which is meant to prevent blackouts.
Becker estimated that Californians are spending about $1 billion per year to “keep expensive peaker plants available for short-term demand,” both through resource adequacy payments and via state emergency funding to extend the lifespan of three coastal power plants, which were slated to close years ago to reduce their harmful impact on marine life.
“At the same time, we have underutilized assets like home batteries and EVs and smart thermostats,” he said.
SB 913 would order the California Public Utilities Commission to design clearer pathways for those assets to count toward resource adequacy.
That could allow VPPs to help displace gas peaker plants. Overall, VPPs could provide more than 15% of the state’s peak grid demand by 2035 and deliver $550 million in annual utility customer savings, according to a 2024 analysis conducted by the energy consultancy The Brattle Group for GridLab. About $417 million of those savings would come from deferring the need for generation capacity, the report found — a category of costs that includes resource adequacy.
Home batteries have already proved that they’re ready and able to meet these peak grid needs, Becker said. In particular, the Demand Side Grid Support program, one of California’s most successful VPP programs to date, has grown to more than a gigawatt of capacity as of last year.
DSGS has shown that its fleet of home batteries can be relied on much like a traditional power plant. In a test of the program over two consecutive hours during a late afternoon in July 2025, roughly 100,000 home batteries delivered about 476 megawatts of energy — enough power to match the output of a typical gas peaker plant.
Despite this performance, the DSGS program has been severely underfunded over the past two years and is now facing the threat of being disbanded entirely. VPP proponents are pushing legislators and the Newsom administration to keep it alive.
SB 913 largely uses the DSGS program as a model for how the California Public Utilities Commission should order the state’s three major utilities to design broader VPP programs.
“DSGS has been a very successful program, and it’s the thoughtful design elements that have made it that way,” said Erik Lyon, an energy regulatory manager at Renew Home. “That’s the key thing to understand about SB 913. The latest version of the bill actually names DSGS as a model.”
Renew Home manages millions of Google Nest thermostats that control air conditioners and home heating systems to reduce energy use and relieve grid peaks across the country, including in California. But to date, California’s demand-response programs have severely limited the role of such assets in addressing resource adequacy.
There are a lot of reasons for these limitations. Most of the demand-response programs in California require customers and the VPP companies that are enlisting them to undergo complicated and time-consuming enrollment processes, Lyon said. They also impose problematic compensation structures that can penalize participants on the basis of what VPP companies say are inaccurate measurements of how much relief they’ve actually provided to the grid.
The design elements that SB 913 adopts from DSGS, by contrast, offer a lot more flexibility for participants, according to Lyon. The bill instructs the CPUC to “streamline the enrollment process to eliminate these common and well-documented problems” that have been cumbersome for customers participating in traditional demand response programs, he said. And it calls for pathways to allow customers to enroll individual batteries, EV chargers, smart thermostats, or other devices that are actively reducing energy use, he said.
SB 913 also instructs the CPUC to use “weather normalized” approaches to measuring customers’ contributions to grid relief, Lyon said. That could help solve a measurement problem often associated with weather-sensitive devices like thermostats, ensuring that household contributions are emphasized during peak days when they are using more air conditioning or heat but not penalized for low load reductions on mild days, he said.
The California Public Utilities Commission has been leery of relying on demand- response programs in the past. But VPP backers say that perspective is based on its analysis of traditional programs, with all their flaws and gaps in accurate measurement.
Renew Home has been working with other utilities in other states and the companies that manage their home thermostat programs to test and verify more modern approaches to measuring the impact of lots of home thermostats turning down their air-conditioning use in response to utility signals, Lyon pointed out.
This should give the CPUC more confidence that it’s getting the grid relief promised, he said. “You can have statisticians dig around in that data and show how it works in ways that are really hard to fake.”
SB 913 also takes on a key problem for households that are increasingly installing batteries alongside rooftop solar: getting compensation for the power they can feed back to the grid.
Today, almost none of the state’s VPP programs allow that, said Jonathan Hart, policy director at the trade group California Solar and Storage Association.
Instead, those programs only allow homes to reduce their grid consumption to zero, he said — which means “utilities are not really accounting for what could be tapped into.”
State regulators have created some rare exceptions to this “no export” rule — including for the DSGS program. Under those exceptions, companies are allowed to measure the power flowing from batteries to the grid using the battery inverters themselves, rather than the utility-owned smart meters.
What’s missing right now is a way to account for that flow of electrons to the grid for resource adequacy, he said.
SB 913 would explicitly order the CPUC to develop a methodology that will give credit for energy exported to the grid in consultation with the California Energy Commission, which currently manages the DSGS program, and the California Independent System Operator, which manages the state’s transmission grid and energy markets.
That won’t be a simple task. CAISO has traditionally required that any power exported from home batteries must be measured via special stand-alone meters, as is required for utility-scale energy resources.
But these rules designed for utility infrastructure don’t work for programs that need to be cost-effective for homes and businesses, said Kurt Johnson, community energy resilience director at The Climate Center, a nonprofit group that supports SB 913.
The “revenue-grade meters” that CAISO requires battery-equipped homes to install would add an extra $800 to $1,000 per home, Johnson said. “If you require that, you’re going to crush the economics” of VPPs. Modern home-battery inverters and smart thermostats can meter themselves at a fraction of that cost, he said.
Hart noted that CAISO is working on rule changes that could allow distributed energy resources like home batteries to be integrated into its markets.
The grid operator hasn’t yet accepted the idea that VPPs should be able to earn resource adequacy value for battery power that’s exported to the grid, Hart said. But recent proposals that might allow individual batteries to be credited for their exported power indicate that there’s room for compromise on that front, he noted.
Sunrun and Tesla Energy, which collectively manage by far the largest share of rooftop solar–charged home batteries enrolled in DSGS, agree that California is missing out under its current regulatory regime.
“Building on this success means creating long-term pathways for DERs to enter the resource adequacy and CAISO wholesale energy markets,” said Lauren Nevitt, Sunrun’s senior director of policy. “SB 913 endeavors to do just that.”
Colby Hastings, senior director of residential energy at Tesla, said that the company has roughly 3 gigawatts of distributed battery capacity deployed in the state. “Enabling these resources to provide grid value will put downward pressure on rates, but we are not seeing urgency on using them,” she said. “We need faster action.”
A handful of Democratic-led states are targeting energy-efficiency programs in an attempt to provide relief on soaring utility bills.
It’s surprising, given the broad support energy-efficiency programs have among Democrats — and the fact that these incentives produce energy savings that benefit both the climate and all consumers. The short-term savings may be tempting, advocates say, but chasing them is misguided.
“The subject of affordability is a serious one across many states across the country. People are hurting, and energy costs are too high,” said Forest Bradley-Wright, state and utility director for the American Council for an Energy-Efficient Economy. “Energy efficiency did not cause the energy affordability crisis, and the problem can’t be solved by cutting energy efficiency.”
It’s the equivalent of trying to slash your grocery bill by eating out at restaurants more often, he said.
Maryland lawmakers earlier this month passed a sprawling package aimed at improving energy affordability, which Gov. Wes Moore is expected to sign into law. One of the legislation’s major provisions calls for lowering the state’s emissions-reduction targets through 2035, thus shrinking the amount utilities must spend on efficiency programs that help reduce carbon pollution. Proponents say the measures will save residents at least $150 per year.
A wide-ranging Massachusetts energy affordability bill would cut $1 billion in spending from the final year of the state’s three-year, $4.5 billion energy-efficiency budget. State utility regulators already ordered a $500 million reduction in the plan last year.
In Rhode Island, Gov. Dan McKee’s proposed budget calls for capping the state’s next three-year energy-efficiency plan at $75 million per year, a notable drop from the $95 million recently approved for 2026.
Champions of these proposals say they offer ways to directly and quickly get residents immediate savings. The energy-efficiency programs are paid for by fees charged to customers’ bills, so if you shrink the program, you shrink the bills, the thinking goes. And every dollar counts, they say, when prices are rising so much, so quickly.
Opponents, however, say efficiency programs actually save everyone money in the long run — and even in the short run for households that take advantage of the incentives. The proposed cuts, therefore, are a misguided attempt at a quick fix that will only make things worse down the road, say many climate and consumer advocates.
If these arguments about long-term gains are accurate — and plenty of reports suggest they are — then why are lawmakers in states dominated by Democrats embracing the idea of scaling back energy efficiency? And why aren’t constituents rallying to push their elected officials to preserve long-term savings? We found three likely reasons.
It’s not easy to lower energy costs.
A monthly electricity bill includes multiple components: There’s the costs for the power supply and the wires, poles, and substations needed to carry that energy; the guaranteed profit for utilities; and the fees that pay for programs like energy efficiency.
Lowering the cost of the power supply would be an immense, long-term effort at the crossroads of public policy, politics, and technology, all made even more uncertain by fluctuations in the global energy markets. The massive transmission and distribution system needs maintenance and upgrades to operate properly, making it difficult — and incredibly slow — to lower costs on that portion of the bill.
“These costs are technically and legally problematic to unwind,” Bradley-Wright said.
Lawmakers, however, can do something about fees by trimming the budgets of the programs they fund. The savings from this approach are generally modest. The promised decrease in Maryland breaks down to about $12.50 per month, only part of which comes from efficiency reductions. Rhode Island’s cuts would shave a few dollars per month off the average bill.
The savings would appear quickly, however. Maryland lawmakers, for example, say they expect consumers to see the difference in their bills within months.
“The thing about surcharges like this is, it is one of our most direct tools,” said Maryland Del. Marc Korman (D), a supporter of his state’s legislation. “We don’t want to forsake all efforts at energy efficiency, but we want to try to provide a little bit of relief for some time if we can.”
If you haven’t taken advantage of an energy-efficiency incentive, it’s easy to feel like you are paying for someone else to save money when you hear about the incentive your co-worker is getting to switch from oil to a heat pump.
That’s not the whole story, though. Efficiency programs benefit the entire system — not just direct participants, although these long-term systemic savings are largely invisible. The programs reduce demand on the grid, which means utilities don’t have to pay as much — or charge customers as much — to maintain and upgrade their infrastructure. Lower grid demand can also curtail the need for dirtier and costlier sources of power, like oil or coal.
From 2016 to 2024, for example, Massachusetts spent about $8 billion through its Mass Save energy-efficiency programming. That investment led to $16 billion in savings and reduced costs — not including the health and environmental benefits — according to analysis from the Acadia Center. But these mechanisms operate entirely unseen. It’s a tough combination: Consumers see the fee on their bill but not the process by which efficiency programs help slow price increases.
“This kind of distance from the effectiveness of these programs is probably a big barrier,” said Anandita Sabherwal, a research associate at Princeton University’s Behavioral Science for Policy Lab.
The economics of energy is exceptionally complex, and the widely varied messages coming from elected leaders, regulators, utilities, and our cash-strapped neighbors can make it hard to pin down reality: Am I paying more for energy efficiency than I am benefiting from it? Are these programs just feel-good measures that do nothing for my bottom line?
So when lawmakers, federal officials, and that guy in the community Facebook group all start questioning efficiency programs, constituents might not know what to think — or what to ask of their elected representatives.
These dynamics certainly come into play when Democratic leaders — traditionally the driving force behind energy efficiency and clean energy spending — start to scapegoat such programs. In Massachusetts, Rep. Mark Cusack (D), the sponsor of the affordability bill, suggested that Mass Save was using its money ineffectively, saying the proposed $1 billion cut would affect only the “bloated” marketing and administration budget, not consumer incentives. It’s a contention firmly disputed by advocates, but the claim still has an impact.
“It can be a very demotivating experience for citizens,” Sabherwal said. “It might lead them to choose the short-term benefit.”
A much-discussed “return to coal” by some countries in the wake of the Iran war is likely to be far more limited than thought, amounting to a global rise of no more than 1.8% in coal power output this year.
The new analysis by thinktank Ember, shared exclusively with Carbon Brief, is a “worst-case” scenario and the reality could be even lower.
Separate data shows that, to date, there has been no “return to coal” in 2026.
While some countries, such as Japan, Pakistan and the Philippines, have responded to disrupted gas supplies with plans to increase their coal use, the new analysis shows that these actions will likely result in a “small rise” at most.
In fact, the decline of coal power in some countries and the potential for global electricity demand growth to slow down could mean coal generation continues falling this year.
Experts tell Carbon Brief that “the big story isn’t about a coal comeback” and any increase in coal use is “merely masking a longer-term structural decline”.
Instead, they say clean-energy projects are emerging as more appealing investments during the fossil-fuel driven energy crisis.
The conflict following the US-Israeli attacks on Iran has disrupted global gas supplies, particularly after Iran blocked the strait of Hormuz, a key chokepoint in the Persian Gulf.
A fifth of the world’s liquified natural gas (LNG) is normally shipped through this region, mainly supplying Asian countries. The blockage in this supply route means there is now less gas available and the remaining supplies are more expensive.
(Note that while the strait usually carries a fifth of LNG trade, this amounts to a much smaller share of global gas supplies overall, with most gas being moved via pipelines.)
With gas supplies constrained and prices remaining well above pre-conflict levels, at least eight countries in Asia and Europe have announced plans to increase their coal-fired electricity generation, or to review or delay plans to phase out coal power.
These nations include Japan, South Korea, Bangladesh, the Philippines, Thailand, Pakistan, Germany and Italy. Many of these nations are major users of coal power.
Such announcements have triggered a wave of reporting by global media outlets and analysts about a “return to coal”. Some have lamented a trend that is “incompatible with climate imperatives”, while others have even framed this as a positive development that illustrates coal’s return “from the dead”.
This mirrors a trend seen after Russia’s invasion of Ukraine in 2022, which many commentators said would lead to a surge in European coal use, due to disrupted gas supplies from Russia.
In fact, despite a spike in 2022, EU coal use has returned to its “terminal decline” and reached a historic low in 2025.
So far, the evidence suggests that there has been no return to coal in 2026.
Analysis by the Centre for Research on Energy and Clean Air found that, in March, coal power generation remained flat globally and a fall in gas-fired generation was “offset by large increases in solar and wind power, rather than coal”.
However, as some governments only announced their coal plans towards the end of March, these figures may not capture their impact.
To get a sense of what that impact could be, Ember assessed the impact of coal policy changes and market responses across 16 countries, plus the 27 member states of the EU, which together accounted for 95% of total coal power generation in 2025.
For each country, the analysis considers a maximum “worst-case” scenario for switching from gas to coal power in the face of high gas prices.
It also considers the potential for any out-of-service coal power plants to return and for there to be delays in previously expected closures as a result of the response to the energy crisis.
Ember concludes that these factors could increase coal use by 175 terawatt hours (TWh), or 1.8%, in 2026 compared to 2025.
(This increase is measured relative to what would have happened without the energy crisis and does not account for wider trends in electricity generation from coal, which could see demand decline overall. Last year, coal power dropped by 63TWh, or 0.6%.)
Roughly three-quarters of the global effect in the Ember analysis is from potential gas-to-coal switching in China and the EU.
Other notable increases could come from switching in India and Indonesia and – to a lesser extent – from coal-policy shifts in South Korea, Bangladesh and Pakistan.
However, widely reported policy changes by Japan, Thailand and the Philippines are estimated to have very little, if any, impact on coal-power generation in 2026. The table below briefly summarises the potential for and reasoning behind the estimated increases in coal generation in each country in 2026.
Dave Jones, chief analyst at Ember, stresses that the 1.8% figure is an upper estimate, telling Carbon Brief:
“This would only happen if gas prices remained very high for the rest of the year and if there were sufficient coal stocks at power plants. The real risk of higher coal burn in 2026 comes not from coal units returning…but rather from pockets of gas-to-coal switching by existing power plants, primarily in China and the EU.”
Moreover, Jones says there is a real chance that global coal power could continue falling over the course of this year, partly driven by the energy crisis. He explains:
“If the energy crisis starts to dent electricity demand growth, coal generation – as well as gas generation – might actually be lower than before the crisis.”
Energy experts tell Carbon Brief that Ember’s analysis aligns with their own assessments of the state of coal power.
Coal already had lower operation costs than gas before the energy crisis. This means that coal power plants were already being run at high levels in coal-dependent Asian economies that also use imported LNG to generate electricity. As such, they have limited potential to cut their need for LNG by further increasing coal generation.
Christine Shearer, who manages the global coal plant tracker at Global Energy Monitor, tells Carbon Brief that, in the EU, there is a shrinking pool of countries where gas-to-coal switching is possible:
“In Europe, coal fleets are smaller, older and increasingly uneconomic, while wind, solar and storage are becoming more competitive and widespread.”
In the context of the energy crisis, Italy has announced plans to delay its coal phaseout from 2025 to 2038. This plan, dismissed by the ECCO thinktank as “ineffective and costly”, would have minimal impact given coal only provides around 1% of the country’s power.
Notably, experts say that there is no evidence of the kind of structural “return to coal” that would spark concerns about countries’ climate goals. There have been no new coal plants announced in recent weeks.
Suzie Marshall, a policy advisor working on the “coal-to-clean transition” at E3G, tells Carbon Brief:
“We’re seeing possible delayed retirements and higher utilisation [of existing coal plants], as understandable emergency measures to keep the lights on, but not investment in new coal projects…Any short-term increase in coal consumption that we may see in response to this ongoing energy crisis is merely masking a longer-term structural decline.”
With cost-competitive solar, wind and batteries given a boost over fossil fuels by the energy crisis, there have been numerous announcements about new renewable energy projects since the start of war, including from India, Japan and Indonesia.
Shearer says that, rather than a “sustained coal comeback” in 2026, the Iran war “strengthens the case for renewables”. She says:
“If anything, a second gas shock in less than five years strengthens the case for renewables as the more secure long-term path.”
Jones says that Ember expects “little change in overall fossil generation, but with a small rise in coal and a fall in gas” in 2026. He adds:
“This would maximise gas-to-coal switching globally outside of the US, leaving no possibility for further switching in future years. Therefore, the big story isn’t about a coal comeback. It’s about how the relative economics of renewables, compared to fossil fuels, have been given a superboost by the crisis.”
As data centers drive electricity demand to new heights and consumers struggle with rising energy costs, cheap, clean power remains out of reach in much of Virginia: Nearly two-thirds of counties outright ban or severely restrict large solar farms.
But that’s about to change.
Virginia Gov. Abigail Spanberger, a Democrat, last week enacted a new law that voids community-wide prohibitions on solar fields and establishes new siting guidelines for the facilities. Starting July 1, when the law takes effect, local governments can still deny permits to solar developers but must submit their rationale for doing so to state regulators.
“Localities still are in the driver’s seat here. They can still deny every project from now until the end of time if they want,” said Evan Vaughan, executive director of the Mid-Atlantic Renewable Energy Coalition, a nonprofit that represents over 50 large-scale solar, storage, and wind developers and manufacturers.
But, he added, given rising prices and pressures on farmers from tariffs and fertilizer shortages, “there may be more interest in rural communities to see solar projects and to at least hear them out about the benefits that they can provide.”
Virginia is fertile ground for large-scale solar.
The state requires its largest utilities to produce 100% renewable energy by 2050, and solar — combined with battery storage — is widely viewed as the lowest-cost way to meet that mandate. Solar arrays can be built more quickly than large gas power plants, making the carbon-free resource a vital way to meet growing energy demand in the state, which is the data center capital of the world. Solar is also insulated from the price volatility inherent to natural gas because it requires only the sun for fuel.
Even with widespread limitations on development, Virginia is No. 9 in the nation in installed solar capacity and gets almost 10% of its electricity from the clean energy source. Nationwide, solar and storage together are set to make up nearly 80% of new utility-scale electricity capacity built in the country this year, per U.S. Energy Information Administration data.
“Affordability is key,” Vaughan said. “Predictability is also key.”
Though the new law is no silver bullet, it’s been long sought by the renewables industry and by state Sen. Schuyler VanValkenburg, a Democrat who represents the Richmond suburbs and is one of its sponsors.
VanValkenburg promoted similar bills in 2024 and 2025, starting with a simpler proposal that prohibited solar bans but didn’t contain siting criteria. He spent two years negotiating with fellow lawmakers, conservationists, and others to craft the new law.
“This milestone has been years in the making,” VanValkenburg said in a statement, “and is the product of close collaboration among bill patrons, solar developers, and environmental advocates.”
The proposal cleared both chambers of the Virginia General Assembly in March. Rather than sign it as passed, Spanberger offered two technical amendments to the measure earlier this month. The General Assembly, which Democrats seized after campaigning on energy costs last November, adopted those changes on April 22.
The measure isn’t without detractors. It passed along party lines, and drew opposition from county governments and the state’s Farm Bureau as it moved through the legislature. Two conservation groups — Friends of the Rappahannock, a river protection group, and The Piedmont Environmental Council — also voiced worry about the law’s approach.
Virginia’s move to expand solar comes as local restrictions on renewable energy proliferate nationwide. Farmland has become a particular flash point for opposition to solar development, as the flat open fields often make prime spots for solar panels.
Vaughan is optimistic that the law will unleash more solar power sooner rather than later. Though the statute won’t be on the books until this summer, some developers may have plans to apply for connection to the PJM grid this week.
“This has been pretty clearly heading for passage for a while,” Vaughan said. “That may have sent folks to take a risk and propose projects in parts of Virginia that were not previously viable. There may be some low-hanging fruit from an interconnection standpoint.”
He added, “I have no special knowledge of that. I’ll be waiting with bated breath to see what happens.”
Most people in the world would think very little before flicking on the lights, charging a mobile phone or turning on a laptop to read this.
But that’s a very different reality from the almost 700 million people in the world who have no access to electricity. While this number is large, it has halved this century, falling from 1.35 billion to 675 million. You can see this in the chart.
However, this progress has been far from even. The number has fallen across all regions except Sub-Saharan Africa, where it has increased.
That doesn’t mean no progress has been made: the share of people in Sub-Saharan Africa with electricity has doubled, rising from 26% to 53%. But population growth has outpaced this expansion, meaning the number of people without electricity has still risen.
Nuclear energy is experiencing a global resurgence.
In the U.S. and Europe, a long-wary public has started to warm once again to the sector. Taiwan, which shuttered its last nuclear power plant last May, is looking to restart at least one facility in the wake of the energy crisis spurred by the Iran war. Fifteen years after the Fukushima nuclear disaster, Japan is now hoping to double its nuclear fleet over the next decade and a half.
But which countries lead the way on this source of carbon-free energy? It depends on how you look at it.
The U.S., the longtime global leader on nuclear, is still at the top of the heap in terms of pure electrical output, followed by China, according to data from think tank Ember. While France is third in terms of production, it gets the highest share of its needs met by atomic power, the result of a push in the 1970s to make the country energy independent. Russia — which completed the world’s first nuclear power plant under the Soviets in 1954 — is fourth in terms of total electricity. South Korea rounds out the top five.
As for what’s in store, China is developing new reactors at a far faster rate than any other country.
The nation has 60 nuclear reactors in operation, and it’s actively building another three dozen or so. To put it in context: Nearly half of all nuclear power plants under construction worldwide are in China. No other country is even in double digits.
That growth is evident in recent electricity-generation figures. China produced 37 more terawatt-hours from nuclear last year than it did in 2024, bringing it to a total of 488 TWh in 2025. At the rate the country is building new facilities, its reactor fleet should eclipse that of the U.S. by 2030.
Still, the U.S. is trying to kick-start its stagnant nuclear industry and retain its position at the top.
Not only is public sentiment toward nuclear on the upswing in America, but also the energy source has broad support from both parties. President Donald Trump wants the iconic nuclear firm Westinghouse to start building 10 of its AP-1000s before 2030, for example. The Biden administration, for its part, issued a loan to fund the first nuclear restart in U.S. history at the Palisades facility in Michigan, and through the Inflation Reduction Act introduced a nuclear-energy tax credit, which Trump kept in place, unlike incentives for wind and solar.
It remains to be seen whether these efforts — and many others at the federal and state levels — will amount to a wave of new nuclear construction in the U.S. No new large-scale nuclear facilities are underway in the country today.
All in all, the world generated a record amount of nuclear power in 2025 — and it’s looking like that number will only go up in the years to come.
A narrow complaint to a federal energy commission could have wide implications for the solar industry and the electric grid — both in North Carolina, where it originated, as well as nationwide.
At issue is a unique planning scheme that’s been years in the making. Duke Energy, the state’s predominant utility, is moving to proactively upgrade poles and wires to create room for prospective solar farms. Rather than making improvements pegged to specific projects and then charging solar developers for the full cost, as it did in the past, the company is now building in anticipation of future grid needs and spreading the costs among all customers.
In recent years, state regulators have pushed Duke to take this approach to alleviate grid congestion. The company is thought to be the first utility in the country to address local transmission needs in this way, even though it is far from the only one with a long backlog of projects waiting to plug into the grid.
But one set of Duke customers isn’t happy. North Carolina’s electric member cooperatives, which buy most of their power wholesale from the utility, filed a complaint with the Federal Energy Regulatory Commission in February over four grid projects. They argue that the cost of the upgrades — $57 million, in this case — should not be distributed evenly among all customers. Instead, they want solar developers to pay half the total cost.
Many observers believe the protest is on shaky legal ground. Yet FERC is chaired by an appointee of President Donald Trump, who is known to attack renewable energy regardless of the law. The commission is expected to make a decision by the fall, and if it rules in the co-ops’ favor, experts say the ripple effects could be dire.
For one, the solar projects banking on the four grid upgrades could falter if they are forced to bear millions of dollars in new expenses. A ruling for the plaintiffs could also send Duke back to its old transmission planning method — a strategy criticized as costly, ineffective, and hostile to new solar.
“It would be hugely disruptive to the solar industry, but also to the development of the transmission system in the Carolinas more generally,” said Ben Snowden of Fox Rothschild LLP, an attorney for solar developers who isn’t directly involved in the case. “It would be a huge mess.”
What’s more, a decision for the co-ops could set the stage for federal meddling in local grid planning.
“Better-planned transmission will save ratepayers money while providing a more reliable grid,” said Chris Carmody, executive director of the Carolinas Clean Energy Business Association. “This complaint could establish precedent for expensive slowdowns and federal interference in state decision-making.”
Duke’s current approach to network upgrades arose because the old one was failing.
As North Carolina policymakers passed laws to speed the clean energy transition in the 2000s and 2010s, Duke was flooded with requests from developers looking to bring large-scale solar arrays online.
To accommodate these projects, the utility sometimes had to replace lines, poles, and other infrastructure. Whenever that was the case, Duke sought to charge 100% of those costs directly to solar developers. Some paid up and connected to the grid, but others balked and withdrew or were delayed indefinitely.
“Every project was studied, one after the other, and the first project to trigger an upgrade was assigned the entire cost of that upgrade,” Snowden said, even if the improvement made way for lots of other projects to interconnect, too.
“The part of Duke’s system that was most conducive to solar got to the point where it was — in Duke’s view — pretty much at capacity,” he said. Any new generator — solar or otherwise — that sought to interconnect in that area would be tagged with tens or hundreds of millions of dollars of upgrades. “The queue got clogged, and it was stuck for a couple of years.”
Over time, the logjam contributed to a slowdown in renewables. New large-scale solar installations plummeted in 2022, according to data from the Solar Energy Industries Association, falling to about 200 megawatts from a peak in 2017 of nearly 1.2 gigawatts.
The most congested areas on the grid became known collectively as the “Red Zone.” Duke, developers, and other parties deemed over a dozen projects — to upgrade lines, replace poles, and make other improvements — necessary. But the disrepair endured because no one could pay for them.
Then, in 2022, the North Carolina Utilities Commission began to turn the ship. The commission ruled that Red Zone upgrades were “appropriate” and “reasonable.” The projects would enable over 3.7 gigawatts of solar to connect to the grid, commissioners said, while providing “operation and resiliency benefits.”
Crucially, regulators also laid the groundwork for upgrade costs to be shared by all customers, instead of paid for by developers alone. Finally, the commission noted flaws in Duke’s transmission planning strategy and urged the company to “engage with stakeholders” to improve its process.
The company did just that, workshopping the Red Zone projects with interested parties and setting up a scheme to identify future grid needs that would provide multiple benefits.
“Duke — pulled kicking and screaming — has made pretty big strides on modernizing its transmission planning,” said Nick Guidi, senior attorney at the Southern Environmental Law Center. “Kudos to Duke for adopting that process.”
Duke didn’t respond to a request for comment for this story. But the company told FERC that the four contested upgrades were on the original Red Zone list and had been extensively vetted by a range of parties — including the state’s member cooperatives.
The Red Zone projects, Duke wrote, “were identified through years of collaborative local transmission planning … and selected because they provide broad, system‑wide reliability, resiliency, and economic benefits that far exceed their costs.”
The company also noted the projects will “help reduce overall power costs for all users” and even facilitate new gas generation in which the co-ops have partial ownership.
A spokesperson for the North Carolina Electric Membership Corporation, the association of 25 rural co-ops bringing the challenge against Duke, declined to speak to Canary Media for this story.
The co-ops’ complaint doesn’t make clear why they chose to object to the four improvement projects in question — two in Erwin, halfway between Raleigh and Fayetteville; one in Sanford, in the state’s dead center; and one in Camden, just west of the Outer Banks.
But their protest repeatedly states that the improvements are “proactive solar upgrades” that primarily help solar companies. A follow-up filing dismisses systemwide reliability and other benefits asserted by Duke as a “barrel of red herrings.”
The $57 million that Duke has assigned to customers for the four upgrades is a “simple unfairness,” the complaint says. Customers should bear only half those costs, and the co-ops’ share should be reduced from $802,000 per year to $401,000. The rest, they argue, should be borne by solar developers, the projects’ “primary beneficiaries.”
“That’s a really faulty premise,” Snowden said. “That’s like saying that the water pipes that run down my street are for the benefit of the people who sell me water.”
What’s more, clean energy and consumer advocates say, the proactive nature of the Red Zone projects is a good thing — unlike Duke’s old “Whac-A-Mole” approach — and their price tag is appropriately rolled into the transmission fees the utility charges its customers.
“You have to spread the costs out across the broader grid,” said Guidi of the Southern Environmental Law Center, “because they provide benefits to the broader grid.”
Perhaps the $401,000 in savings would trickle down to the co-ops’ 1 million metered customers, representing 2.8 million North Carolinians. But, Guidi said, “It would be a drop in the bucket.”
The impact could be more acute for solar companies, which tend to operate on thin margins. The extra costs could conceivably cause developers relying on the four upgrades to withdraw, Snowden said. However, he added, “I think the bigger danger is: Do you undermine Duke’s willingness to continue with proactive transmission planning?”
The complaint is the first of its kind, making its outlook murky.
“It’s a very big swing from a legal standpoint,” Snowden said. “There are some very serious questions about the relief that they’re seeking, including whether FERC has the jurisdiction to provide this relief at all.”
The five-member commission still contains three appointees from former President Joe Biden, and Trump’s choice for chair is generally considered qualified and conventional.
But when disputes over renewable energy reach a body even remotely touched by the president, all bets are off.
“They’re trying to identify these four lines as solar lines,” Guidi said. “Whether that’s their belief, or whether they are trying to play to a federal administration generally not friendly to solar, that is seen throughout their complaint.”
Furthermore, the petition clearly signals that more challenges could be on the way to Red Zone improvements, as it calls the four upgrade projects “the tip of an iceberg.”
“This is just the start,” Guidi said. “I don’t think they expect it to end here.”
Last year was a huge one for renewable energy around the globe — but nothing showed up quite like solar power.
This week, energy think tank Ember released its review of where the world’s electricity came from in 2025, and it’s full of wins for clean energy. Last year marked the first time global renewables generation exceeded coal, with solar, wind, hydropower, and biofuels delivering just under 34% of the world’s power to coal’s 33%.
That milestone couldn’t have happened without solar power, which last year overtook wind to become the world’s biggest renewable power source. Here are three more takeaways that spotlight solar’s growth — and why it’s on track to continue.
1. Lots of countries are relying more on solar power.
Megawatt for megawatt, China is the world’s undeniable solar leader. But many smaller countries get a higher share of their power from solar.
Last year, Chile got a full quarter of its power from solar, while Hungary relied on solar for 27% of its electricity. That’s a huge spike from 2020, when the clean energy source generated less than 10% of the power in each of those countries.
They’re not alone. At least 50 countries relied on solar for at least a tenth of their power last year, up from just 15 countries doing the same in 2020.
2. Solar’s midday peaks are reaching new heights.
It’s no surprise that solar power generation hits its peak around noon. That was clear across last May, when solar generated an average of 25% of the world’s electricity around midday.
That’s a big share, but some individual countries had even more impressive results. The Netherlands generated an average of 77% of its midday power from solar across May 2025, while Hungary got a whopping 91%, easily beating its previous monthlong record of 67%.
The next step for many of these countries? Installing more battery storage so they can hold on to that power when the sun goes down.
3. Fossil fuel–dependent countries have huge untapped solar potential.
Solar is proving itself as a clean solution to rising power demand, but many countries aren’t taking full advantage.
The U.S. saw the third-largest rise in its electricity demand of any country last year, but it met 88% of that new need with clean power. India, meanwhile, saw the second-highest demand growth (after China), yet met more than half of it with fossil fuels.
That doesn’t have to be the case. India gets a ton of sunlight that’s still going untapped, as do Saudi Arabia, Indonesia, Egypt, and other countries that are also still significantly expanding their fossil fuel use.
A judge this week temporarily halted the Trump administration’s enforcement of policies that had effectively blocked solar and wind projects that are on federal land or otherwise need a federal permit, Canary Media’s Maria Gallucci reports. Among the struck-down rules is a directive that required wind- and solar-related decisions to get Interior Secretary Doug Burgum’s personal sign-off, adding costly delays to many projects.
In their lawsuit, clean energy advocates argued that these roadblocks had led to roughly 57 GW of new “wind, solar, hybrid, and offshore wind capacity” being either canceled or put at risk of delay or termination, and jeopardized at least $905 million in investments.
Although the pause is only temporary as the lawsuit works its way through court, the judge in the case said the advocates are likely to succeed in proving the blockade violates federal law.
Global offshore wind soars as U.S. struggles continue
Offshore wind power is sailing forward in China, the United Kingdom, and beyond, according to a new report from the Global Wind Energy Council that Canary Media’s Maria Gallucci dug into this week. More than 9 GW of new offshore capacity came online in 2025, bringing the world’s total offshore wind capacity to about 92 GW.
But back in the U.S., the offshore wind blowback continues. The Trump administration recently made a deal to refund French developer TotalEnergies if it canceled its offshore wind leases, and now, French utility Engie says it’s in talks with the federal government to do the same. Turbine manufacturers are facing struggles of their own, with an American subsidiary of Germany’s EEW Group declaring bankruptcy in New Jersey. GE Renewables is meanwhile looking to get out of its turbine maintenance contract with Vineyard Wind, though a judge struck down its plan earlier this week.
Design by Tom Prater and Kerry Cleaver
The Atlantic Meridional Overturning Circulation (AMOC) is a vast system of ocean currents that helps to distribute heat around the world.
By transporting warm water from the tropics northwards and cold water back southwards, the AMOC keeps Europe warm and plays a role in controlling global rainfall.
It connects into an even larger network of ocean currents that continuously moves water, nutrients and carbon around the world.
Now, the AMOC is under threat from human-caused climate change, as warming seas, melting ice and increased rainfall upset the temperature and salt balance of the North Atlantic.
Scientists have warned that the ocean currents are slowing down – and could eventually become so frail that they no longer transport heat around the globe.
A growing body of research has suggested that, with enough warming, the AMOC could reach a “tipping point” and transition to a weak state for many centuries.
The Intergovernmental Panel on Climate Change (IPCC) has projected that the AMOC will decline over the course of the 21st century as the world warms.
However, whether – and when – currents might “collapse” remains a subject of debate.
The IPCC says a “collapse” before 2100 is unlikely.
However, some scientists have argued climate change could force the AMOC past a “point of no return” over the coming decades that could usher it towards a “shutdown” next century.
A major slowdown or “tipping” of the AMOC could have grave consequences for European temperatures, causing them to plunge – despite global warming.
It could also affect global food supply, sea level rise and global rainfall patterns, or even act as a catalyst that sets off a series of other catastrophic climate “tipping points”.
Below, Carbon Brief explains what the AMOC is and how it is being impacted by climate change.
The article also explores scientific debates around the future of the AMOC, including what the latest research says about the possibility and consequences of a collapse of the ocean currents.
The AMOC is a system of ocean currents driven by variations in seawater density controlled by temperature (“thermo”) and salinity (“haline”). This makes it a “thermohaline circulation”.
Winds also play an important role in powering the AMOC, helping to propel surface currents and draw dense, nutrient-rich water from the ocean’s depths to its top layer.
The AMOC connects into a broader circuit of slow-moving currents – the global thermohaline circulation – that transports heat and nutrients around the world. This system is sometimes described as the “ocean conveyor belt”.
In the high latitudes of the North Atlantic, warm surface water is cooled by the overlying atmosphere. As water evaporates and sea ice forms, salt is left behind in the ocean. As a result, the surface water sinks.
The water then heads south, thousands of metres below the ocean’s surface.
Outside of the Atlantic, this cold water is pulled back to the surface, assisted by ocean mixing and winds in the Southern Ocean. This is known as “upwelling”.
Upon returning to the North Atlantic, warm, salty water in the tropics is then pulled northwards towards Europe, closing the loop.
Upwelling, which occurs in different parts of the Southern, Indian and Pacific oceans, is not technically part of the AMOC, which refers to the northward flow of warm, surface water and southward flow of cold, deep water specifically within the Atlantic Ocean. Nevertheless, it is crucial to the functioning of the AMOC.
It has been estimated that it takes hundreds to thousands of years for a “parcel” of water to make a journey around the globe before returning to the equator in the North Atlantic. (The exact timeframe depends on the route it takes, according to a 2021 Science Advances study.)
The speed of water transportation picks up dramatically in the “upper branch” of the AMOC, as surface water hurtles northward from the equator to the poles, powered by winds.
The Gulf Stream – a key AMOC component that runs from the Gulf of Mexico to northern Europe and is primarily driven by winds – is one of the fastest ocean currents, reaching peak velocities of 2-2.5 metres per second.
The AMOC does not only transport heat. It also plays a role in the transportation of nutrients that support marine ecosystems, as well as supporting the carbon cycle by transporting carbon-rich surface waters to the deep ocean.
Since the mid-20th century, oceanographers have warned that a warming climate could cause a slowdown of the AMOC, with far-reaching consequences for global weather patterns, humans, biodiversity and the carbon cycle. (For more, see: What are the projected impacts of AMOC collapse?)
The warming of the atmosphere due to the rise in greenhouse gases is causing an influx of freshwater into the North Atlantic from melting ice from Greenland.
Human-caused climate change has also been linked to an overall intensification of the global water cycle, meaning that more rainfall and more run-off from rivers ends up in the ocean.
Together, these factors are reducing the saltiness of water in the North Atlantic.
Sea surface temperatures are also rising with climate change.
When water is warmer and less salty, it sinks less easily. This hinders the “deep-water formation” – the process of cold water sinking – in the North Atlantic, slowing down the AMOC.
This has a compounding effect. As the AMOC slows down due to an overload of freshwater, it is able to transport less salty water northwards from the tropics – making the North Atlantic even more diluted. This is known as the salt-advection, or salinity-advection, feedback.
Against this backdrop, warmer air temperatures in the North Atlantic are reducing the ocean waters’ ability to shed heat at the surface and sink – further incapacitating the AMOC.
Experts have sounded the alarm that, with enough warming, the AMOC could weaken to a point where it is no longer able to transport heat and salt around the Atlantic.
A growing number of scientists believe the AMOC could eventually transition into a weak state from which it would not be able to return for centuries – even if warming were reversed.
This makes the AMOC an example of a climate “tipping” element – a part of the Earth’s system that has the potential to dramatically shift once pushed past a specific threshold by human-caused warming – often irreversibly.
US oceanographer Henry Stommel was the first scientist to propose that the AMOC could transition to a much weaker state.
In a 1961 paper, he used a simple model to propose that a thermohaline system could exist in two “stable regimes of flow”.
Stommel suggested that if a thermohaline system was subjected to enough changes in water density – in other words, was diluted with enough freshwater...
...it would collapse into a “new regime”.
Once in this new, weaker state, the system would not be able to simply return to the previous regime, even if conditions returned to their original state.
This is known as “bistability” – the potential of a system to have two different “stable” states. Once the system has been pushed into a different state, it cannot easily be pulled back again.
The bistability of the AMOC has been demonstrated in the years since Stommel’s model in modern climate models of increasing complexity.
A 2026 review study said the “evidence base in favour” of AMOC’s bistability had “broadened over the last years” – and concluded that the present-day AMOC was “in such a regime”.
There is broad consensus that evidence suggests the AMOC has exhibited bistable behaviour in previous ice ages – and that it has been slowing down under modern warming.
However, whether – and when – an AMOC “tipping point” could occur in a world warmed by greenhouse gases remains a live debate. (For more, see: How do scientists project future AMOC trends?)
Since the early 2000s, the strength of the AMOC has been estimated using vertical moorings installed at different locations of the Atlantic Ocean.
The oldest of these monitoring arrays is the RAPID observing system at a latitude of 26.5 degrees north. The array has collected continuous measurements in the mid-Atlantic and at its eastern and western boundaries – near the Bahamas and the Canary Islands – since 2004.
The sensors, which are bolted on to wires, stretch thousands of metres down to the ocean floor and collect measurements of water current, pressure, temperature and conductivity.
Dr Ben Moat, principal investigator of the UK National Oceanography Centre, which maintains the system, tells Carbon Brief that RAPID captures the heat transport of AMOC at its maximum strength:
“The heat that is moved northwards between Florida and the Canary Islands is 1.2 petawatts (PW) of heat – that is equivalent to a million power stations. RAPID was designed specifically to be close to the maximum of that heat transport.”
To get an overall picture of the strength of AMOC, scientists combine RAPID observations with wind observations and measurements of the Gulf Stream captured by an electromagnetic cable in the Florida Straits maintained by the US National Oceanic and Atmospheric Administration (NOAA).
Moat says the RAPID project has “completely revolutionised” scientific understanding of how heat is moved around the Atlantic:
“Until RAPID there was little understanding of how the [AMOC] varied and how it is changing over time.
“Then, along came RAPID and the first results were astounding. Not only did this heat transport vary on daily time scales, it moved on hourly to daily to monthly [time scales]. Now, we are seeing seasonal, inter-year and decadal changes.”
There are now a number of other sensor arrays that help scientists measure the health of AMOC moored in the Atlantic. This includes the OSNAP subpolar array, which has been collecting hourly measurements from the northern boundary of the Atlantic since 2014, as well as the South Atlantic meridional overturning circulation basin-wide array (SAMBA) at 34.5 degrees south, which has been in operation since 2009.
The map below shows the different trans-Atlantic mooring arrays that monitor the AMOC.
Observing arrays in the Atlantic with AMOC transport estimates from OSNAP (green, operational), NOAC 47N (black dashed), RAPID 26N (red), MOVE 16N (magenta), TSAA 11S (black dashed), and SAMBA 34.5S (blue). Credit: Frajka-Williams et al (2019).
The strength of AMOC is measured in sverdrups (Sv), where one unit represents the transport of one million cubic metres of water per second.
The plot below charts observations captured by the RAPID array since 2004.
AMOC strength measured by the RAPID array in Sv. The solid blue line is the average strength of the AMOC in Sv, the solid black line is the trend and the dashed lines the 95% confidence interval for the trend. Source: NOC. Chart by Carbon Brief.
A 2023 review paper which analysed 20 years of RAPID measurements found that average AMOC strength annually was in the range of 15-17Sv between 2011 and 2020, down from 18-19Sv over 2004-08.
In other words, the ocean conveyor belt transported, on average, 2-3m cubic metres less water every second over 2011-20 compared to 2004-08.
However, it notes that the observational record is “still too short” to disentangle the fingerprint of climate change from decade-to-decade natural climate variability.
For example, the paper attributes a steep decline in AMOC strength over 2007-11 – of 0.6Sv each year – to “wind or buoyancy forcing over the North Atlantic rather than anthropogenically forced [human-caused] change”.
It notes that most of the year-on-year variability over this period can be “reproduced by relatively simple wind-forced models – suggesting that the 2009-10 event may have been primarily a wind-forced response”.
A 2025 Geophysical Research Letters paper which looked at RAPID measurements over 2004-23 noted that the AMOC has weakened by roughly 1Sv per decade, across a range of 0.4-1.6Sv.
This downtrend, it said, is “close” to the pace of decline through to 2100 projected by climate models. (For more on models, see: How do scientists project future AMOC trends?)
Scientists will have to wait until at least 2033 – when there will be 29 years of RAPID data – to be able to confidently disentangle the role human-caused climate change is having on the AMOC, according to 2020 Geophysical Research Letters research.
The table below – from the 2023 review – shows average estimates of AMOC strength captured at four trans-Atlantic monitoring arrays (ONSNAP, RAPID, MOVE and SAMBA).
It shows how average AMOC strength at 26.5 degrees north – of 16.9Sv – is broadly consistent with those captured at other arrays, which range from 16.7-17.3Sv.
Determining variations in the strength of AMOC prior to 2004 is more complicated due to the lack of a direct observational record.
Prior to the installation of the RAPID array, direct measurements of the AMOC were limited to a handful of one-off, “snapshot” AMOC observations collected by sensors dropped off research ships.
To gauge changes to AMOC’s strength over a longer period, scientists use indirect ocean observations.
These include ocean temperature and salinity observations, as well as satellite observations of sea surface height.
For example, the existence of the “cold blob” or warming “hole” in the sub-polar gyre region of the North Atlantic has been cited as evidence of a slowdown of the AMOC. This region – the place where the AMOC delivers much of its heat – has cooled as the world has warmed.
This is shown by the map below, where red indicates places which have warmed since the pre-industrial period and blue shows places that have cooled.
(For more on the human causes of the cold blob, see Carbon Brief’s coverage of a 2020 study in Nature Climate Change.)
To trace changes to the AMOC before satellite and sea surface temperature records began, scientists use proxy records held in marine “archives”, such as coral and ocean sediments.
For example, a 2021 Nature Geoscience paper compared a “variety of proxy records”, including deep-sea sediments and ocean temperature patterns, to reconstruct changes to the AMOC since AD400. It found that the ocean currents during the mid-20th century were at their weakest in one thousand years.
Going back even further in time, scientists have used ice cores and ocean sediment to link oscillations of the Earth’s climate during ice ages to the AMOC. This body of research has suggested that Atlantic ocean currents weakened during cold phases and recovered ahead of relatively warmer periods, in cycles lasting from 1,000 to 100,000 years.
The conclusions that have been inferred from indirect datasets can vary widely, given incomplete data and a diversity of approaches to defining an AMOC indicator.
Scientists also use climate models to run “hindcasts” that simulate how the ocean might have behaved in the past. Hindcasts are model runs exploring the recent historical period that allow scientists to understand how well simulations cleave to observations.
However, there are limitations to how well models can replicate changes to ocean patterns. (For more on climate models and AMOC, see: How do scientists project future AMOC trends?)
The Coupled Modelled Intercomparison Project 5 (CMIP5) models developed for the IPCC’s fifth assessment cycle (AR5) indicated a slowdown of the AMOC over the 20th century. In contrast, the CMIP6 models developed for the IPCC’s sixth assessment cycle (AR6) indicated an increase in AMOC strength over the course of the 100-year period.
The IPCC has updated its assessment of 20th-century AMOC behaviour a number of times.
The 2013 Working Group I (WG1) report of AR5 concluded there was “no observational evidence” of a long-term AMOC decline, based on the then-decade long “record of the complete AMOC” and “longer records of individual AMOC components”.
Six years later, the 2019 special report on ocean and cryosphere stated with “medium confidence” that the AMOC had weakened relative to 1850-1900. However, it noted that data was “insufficient” to quantify that weakening or to attribute it to human-caused climate change.
More recently, the 2021 WG1 report of AR6 noted that its confidence levels in “reconstructed and modelled AMOC changes” had decreased. It stated that it had “low confidence” in the weakening of AMOC in the 20th century.
Thus, while direct observations reveal a weakening of AMOC over the last two decades, incomplete data means the picture before the 21st century is less certain.
The term “collapse” is used in different ways in the scientific literature about AMOC.
An AMOC that is no longer able to transport heat around the planet is often referred to as being “collapsed”, “shutdown” or as being in an “off” state.
Other research uses the term ”collapse” to describe the juncture where AMOC has “tipped” – in other words, started an almost-irreversible transition towards an extremely weak state. This is also sometimes described as the “start of collapse” or “AMOC collapse onset”.
The transition of AMOC from the moment of its “tipping” to its stabilisation in a new, weak state would take somewhere up to, or even more than, 100 years, according to recent modelling studies.
Meanwhile, in climate modelling, a collapsed AMOC is typically one that has stabilised at a weak state of between, or below, 3-6Sv – roughly one-fifth to one-third of the strength of AMOC over 2011-20. In these modelled worlds, the AMOC may, or may not, be able to return to a stronger state if warming was reserved.
Prof Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research (PIK) explains that 6Sv is a “common threshold” that researchers use in model runs for a collapsed AMOC. At this strength, he says, the AMOC has just “weak, shallow overturning” and “hardly any influence on heat transport or climate”.
His colleague Prof Niklas Boers at PIK says the definition of AMOC “collapse” is a “matter of convention”. The common characterisation of a collapsed AMOC as one that has stabilised below a certain strength threshold – “regardless of whether it is reversible or not” – is “fair”, he says.
However, Boers notes that this definition does not answer the “practically relevant” question of whether the “AMOC is tipping – in the sense of, can it come back or not?”
Dr René van Westen, a researcher at Utrecht University, says that measuring AMOC in terms of strength in sverdrups does not provide a full picture of AMOC’s ability to redistribute heat. Heat transport around the Atlantic could start to break down well above a 6Sv threshold, he explains:
“AMOC strength is the most compelling [characteristic] because it is very easy to communicate. But it can sometimes give you a mixed view [on AMOC collapse]. There will be instances where you get a shallow residual AMOC that can be above this arbitrary [6Sv] threshold.”
Other variables to look out for when assessing AMOC’s health, according to van Westen, include patterns of oceanic heat transport across Atlantic Ocean latitudes and the presence of “sinking and deep water mass transformation” in the North Atlantic.
To explore how the AMOC might behave in the future – and what the impacts of it might be – scientists turn to climate models.
Climate models have long predicted an AMOC slowdown in response to global warming. However, model projections of the future health of the AMOC vary widely.
In AR6, the IPCC said the AMOC will “very likely decline” over the 21st century across all shared socioeconomic pathway (SSP) scenarios.
(For more on the scenarios themselves, see Carbon Brief’s explainer.)
The IPCC’s projections suggest that in a low-emissions scenario, the AMOC will weaken by about 24% (with a range of 4-46%) by the year 2100, depending on the model. It projects a reduction of 39% (with a range of 17-55%) in a very high-emissions scenario.
An analysis of a “majority cluster” of CMIP6 model projections in a 2020 paper found that, on average, the AMOC could weaken by 34% in a low-emissions scenario and 45% in a very high-emissions scenario by the century’s end, equivalent to a 6-8 Sv decline at the RAPID array.
(When the analysis was not limited to this group of models, the paper projected a decline of 24% in a low-emissions scenario, 29% in a medium-emissions scenario, 32% in a high-emissions scenario and 39% in a very high-emissions scenario by 2100.)
In a 2026 Science Advances paper, researchers attempted to refine estimates of the AMOC’s future behaviour by incorporating real-world observations into model projections. The research found that – once these “observational constraints” are taken into account – model projections show the AMOC could slow down by 51% by 2100 in a medium-emissions scenario.
The line chart below, from a 2026 review paper, illustrates CMIP6 model projections for AMOC’s health over 1850-2100. The black line indicates the maximum strength observed at 26 degrees north and the colourful lines indicate average projections under different emissions pathways from 2014 onwards.
The violin plots on the right shows the spread of AMOC strength outcomes projected by the end of the 21st century under different emissions pathways, as projected by CMIP6 models.
A substantial body of research has found that IPCC models lean towards unrealistic levels of stability in the AMOC. This has been backed up by hindcasts.
The IPCC acknowledges the limitations of current tools for projecting the future health of AMOC. In AR6, it stated that – despite having “high confidence” in future AMOC weakening as a “qualitative feature” based on “process understanding” – it has “low confidence” in “quantitative projections” of AMOC decline in the 21st century.
Dr Laura Jackson from the UK Met Office explains why the AMOC is difficult to model:
“The AMOC is not a specific thing – it is the impact of lots of different currents. It is affected by processes happening at small scales, like mixing and eddies which affect how the heat and salt are distributed. We can’t resolve many of these with climate models.”
Common issues with models, according to the 2026 review, are a “too-shallow AMOC pattern, a too-strong recirculation in the upper mid-ocean, a too-weak meridional heat transport and an underestimation of interannual and decadal variability”.
A limitation in IPCC models is that they do not incorporate the impacts of freshwater being added to the north Atlantic as the Greenland ice sheet melts.
To address this limitation, researchers adjust climate models to add levels of freshwater input to the north Atlantic for a fixed length of time. This is known as “hosing”.
To investigate models’ sensitivity to an influx of freshwater in the North Atlantic, six global modelling groups ran a series of “hosing experiments” with eight CMIP6 models (from six modelling centres) as part of the North Atlantic Hosing Model Intercomparison Project.
In findings published in 2023, the researchers noted that half the models tested in the experiment “recovered” after “hosing of 0.3Sv”, whereas the remainder “remained in a weakened state”.
The study explained that the model runs explored are “unrealistic” and not future climate scenarios. However, it said that analysis of the similarities and differences between model responses helps scientists “understand what controls…AMOC response and how the real world may behave”.
Given the limitations of models, in recent years scientists have turned to other methods to understand the future behaviour of the AMOC, including “early-warning signal” studies.
Early-warning signal studies look for other factors in the historical record and model runs that provide an indicator for whether the AMOC is approaching a tipping point.
These can be “statistical indicators” – patterns in data timeseries, such as sea surface temperature or ocean salt content.
They can also be “physics-based indicators”, which are physical processes tied to AMOC stability. These mechanisms are linked to the dynamics of the ocean, such as water buoyancy and freshwater transport.
An example of a study that looked at statistical indicators is a 2021 Nature study that analysed four temperature and four salinity data series linked to AMOC strength. It concluded there was “strong evidence that the AMOC is indeed approaching a critical, bifurcation-induced transition”.
(When a system undergoes a “bifurcation” – which means to divide into two branches – it is subsequently difficult, if not impossible, for the system to revert to its previous state.)
A 2023 Nature Communications paper analysed sea surface temperature in the sub-polar gyre region to make a headline-grabbing prediction of a “forthcoming collapse” of the AMOC. The paper projects that AMOC “collapse” could “occur” between 2037 and 2109 – and most likely around the middle of this century.
Meanwhile, a 2024 Science Advances study said it had identified a new “physics-based early-warning signal” that showed AMOC is “on route to tipping”. The indicator used related to the minimum amount of freshwater transported by AMOC at the southern boundary of the Atlantic.
A 2026 Communications Earth & Environment paper identified “abrupt” changes to the path of the Gulf Stream as an “early-warning indicator” of an AMOC “collapse” or “tipping”.
PIK’s Rahmstorf says that debate remains about the usefulness of studies which look for signs that indicate the collapse of the AMOC. Scientists are still looking for “better, more reliable and observable” warning signals, he says, explaining:
“We are never going to get a [fully] reliable ‘early warning’ because the uncertainties around the data availability are just too large. That was already my feeling in the early 2000s when this kind of work started. I thought that, theoretically, this is nice – if only we had the data. But, the problem is, we don’t have 100 years of accurate AMOC data.”
His colleague Boers says that early-warning studies can help scientists interpret whether a system is moving towards a tipping point, but should not be used to make timing predictions:
“The AMOC’s stability has declined. It has moved closer towards a possible tipping point. But we cannot say when that might happen. Even if we knew the exact evolution of future temperatures, then there’s still way too many other uncertainties to make any meaningful prediction of the time at which this could happen.
“So, early warning in terms of a prediction? No way. It just doesn’t work.”
In AR6, the IPCC notes it has “medium confidence” that the decline of AMOC will not involve an “abrupt collapse” before 2100. (An “abrupt” change in IPCC lingo is an event taking place in three decades or less.)
The IPCC’s findings were backed up by a 2025 Nature study that examined the future stability of the AMOC in 34 climate models adjusted to simulate varying levels of greenhouse gas emissions and freshwater input.
The researchers found that an AMOC collapse – defined in a correction notice as a “weakening to below 6Sv” – was “unlikely” this century, noting that, “in all cases”, the ocean circulation was sustained “by upwelling in the Southern Ocean, driven by persistent Southern Ocean winds”.
(The paper in question prompted some debate around how scientists define AMOC “collapse” by 2100.)
A number of recent papers have argued that the risk of AMOC collapse has been underestimated.
For example, a study published in Environmental Research Letters in 2025 explored the future health of AMOC by running a number of IPCC climate models beyond their typical 2100 cut-off. It found that an AMOC shutdown would occur after 2100 in 67% of all runs in a very high-emissions scenario, 30% of all runs under a medium-emissions scenario and 25% in a low-emissions scenario.
The “precursor” to a “weak and shallow AMOC” after 2100 is the collapse of “maximum mixed-layer depth” in the North Atlantic in the middle of this century, according to the study.
The researchers said that “such numbers…no longer comply with the low-likelihood, high-impact event that is used to discuss an abrupt AMOC collapse in AR6 and this assessment needs to be revised in [the IPCC’s upcoming seventh assessment report]”.
(It is worth underlining that the IPCC’s discussion of potential AMOC collapse is in the context of the 21st century, whereas the Environmental Research Letters study explores potential outcomes post-2100.)
Another recent study, published in JGR Oceans in 2025, found that the AMOC could “begin to collapse” as soon as 2063 under a medium-emissions scenario.
The researchers determined that AMOC is on a tipping course once a threshold – a “physics-based indicator” – related to water sinking is crossed. After analysing when this trigger point occurred in various model runs, they pinned the “AMOC tipping threshold” at around 2.5C of global warming above the pre-industrial average.
The research noted that a “previous critical temperature threshold of 4C warming for AMOC tipping” – set out in a 2022 Science paper – “should be revised”.
Van Westen – who was involved in both the JGR Oceans and Environmental Research Letters studies – highlights that both papers identify a threshold likely to be crossed in the 21st century that would mark a “point of no return” for the AMOC. He says:
“The most interesting AMOC dynamics happen after 2100, but most [climate model] simulations are terminated at 2100 because it is computationally too expensive [to run them].
“[Our research shows] that many [simulations to 2100] have already reached a critical value where AMOC has started to tip – a process that could then take 100 years. In those, the [simulated] AMOC might be at 12Sv by 2100, but actually it is already collapsing.”
An AMOC shutdown would transform weather patterns, with drastic consequences for Europe, the Amazon rainforest and food systems.
In AR6, the IPCC summarised the potential effects of an AMOC collapse as follows:
“If an AMOC collapse were to occur, it would very likely cause abrupt shifts in the regional weather patterns and water cycle, such as a southward shift in the tropical rain belt, and could result in weakening of the African and Asian monsoons, strengthening of southern hemisphere monsoons and drying in Europe.”
A 2025 study in Geophysical Research Letters looked at the combined effects of global warming and a full AMOC collapse on Europe. (For more, read Carbon Brief’s in-depth coverage of the research.)
The study found that, in a medium-emissions scenario, greenhouse gas-driven warming would not be able to outweigh the cooling impact of an AMOC shutdown. In this modelled world, cold extremes could approach -20C in London and -48C in Oslo.
The cold temperatures in north-west Europe would be driven by the loss of heat transfer from the tropics via ocean currents, as well as the encroachment of sea ice across northern Europe in winter, the study noted.
Separate research published in 2025 in Hydrology and Earth System Sciences found that an AMOC collapse under a medium-emissions scenario would lead to increasing drought in southern Europe.
The impacts of a shutdown of AMOC on the global south is a growing area of research. There is evidence that the shutdown of the ocean currents could lead to a major rearranging of global monsoon systems in regions where more than half of the world’s population live – and increased drought in the Sahel.
A 2024 Science Advances study found that – in a modelled world without global warming, but a full AMOC collapse – the Amazon rainforest would see a “drastic change” in rainfall patterns with the “dry season set to become the wet season and vice-versa”.
Several studies have shown that sea levels on the east coast of the US will rise more quickly if the AMOC weakens. A 2015 Nature study pointed to a 30% downturn of the AMOC over 2009-10 as one of two factors for an “unprecedented” 128mm jump in sea level north of New York City over the two-year period.
Other research has explored the impact of a collapse of AMOC on food supplies. For instance, a 2020 study in Nature Food found that the collapse of the ocean currents could result in the “widespread cessation of arable farming” in the UK and “losses of agricultural output…an order of magnitude larger than the impacts of climate change without an AMOC collapse”.
Meanwhile, other scientists have warned that damage to the mechanism which allows the ocean to store carbon could lead to more CO2 collecting in the atmosphere.
A 2026 paper, published in Communications Earth & Environment, found that AMOC collapse – defined as a “rapid weakening to a nearly complete shutdown with a maximum strength below 5Sv” – would increase atmospheric carbon dioxide by 47-83 parts per million (ppm).
This, the researchers said, would lead to around 0.2C of additional warming, once “ocean-dynamics-driven cooling” was taken into account. (To reach their conclusions, the researchers ran experiments using a fast Earth system model, exploring scenarios where baseline CO2 levels ranged between 350-600ppm.)
Scientists have noted that the shutdown of the AMOC could have a “cascading” effect on other critical Earth systems, which are themselves at risk of tipping.
Prof Nico Wunderling, a scientist at PIK’s Earth Resilience Science Unit, explains that the AMOC is the “strongest interactor across all of the climate tipping elements” because it links the cryosphere – the portions of Earth where water is in solid form – to the ocean, atmosphere and biosphere. He tells Carbon Brief:
“When the AMOC changes, it changes not only ocean temperatures, which then act on the cryosphere [the Greenland ice sheet, the West Antarctic ice sheet, permafrost and Arctic and Antarctic sea ice], but it changes atmospheric patterns, such as the Intertropical Convergence Zone [a band of low pressure around the Earth which generally lies near to the equator] and other winds in the global climate system. That means rainfall patterns change, which then impacts biosphere [tipping] elements such as the Amazon rainforest.”
The map below shows how the collapse of the AMOC could end up destabilising a number of the Earth’s tipping elements, including the West Antarctic ice sheet and the Amazon rainforest. The red arrows illustrate destabilising effects between different tipping elements.
The AMOC is receiving increasing media attention around the world.
Carbon Brief analysis reveals how the number of news articles to mention “Atlantic Meridional Overturning Circulation” has grown over the past 20 years, from 14 in 2006 to 1,033 in 2024. This is shown in the chart below.
Annual number of articles that mention “Atlantic Meridional Overturning Circulation” over 2006-25, according to Factiva, a news database which counts more than 33,000 newswires and national, international, local and business news sources. Data – which can be viewed here – accessed by Carbon Brief on 5 February 2026.
The chart above is designed to give a sense of trends in media coverage. The overall number of articles discussing AMOC is likely far greater. Carbon Brief limited its analysis to references of the full term “Atlantic Meridional Overturning Circulation” and not the AMOC acronym. (This was done to exclude articles related to, among other things, the Alexandria Mineral Oils Company and “alternative methods of compliance” in aviation.)
There is also frequent conflation in the media of AMOC with its component, the Gulf Stream. Articles that only mention the Gulf Stream are not captured in the analysis.
Coverage of AMOC science is often sensationalist in tone, with journalists frequently evoking catastrophic scenarios depicted in the 2004 blockbuster film The Day After Tomorrow. The film depicts the rapid onset of a new ice age after melting sea ice prompts Atlantic circulation patterns to almost instantaneously collapse.
In 2024 and 2025, 195 and 81 articles, respectively, referenced the disaster film in AMOC coverage, according to Factiva. (This averages at roughly 19% and 9% of the total.)
Jackson from the Met Office says the film helps to feed a common “misconception” that AMOC collapse would occur quickly. She tells Carbon Brief:
“I get the impression some people think that [AMOC collapse] is like in The Day After Tomorrow and happens over a few days. Whereas what we are thinking about happens over decades or maybe a century.”
However, there has been a rise in longer-form, explainer articles about AMOC science.
Over the past two years, the Financial Times, New York Times, New Scientist, Vox, Mother Jones, MIT Technology Review, Washington Post and WIRED have dedicated long-reads to explaining the risks and science of AMOC.
At the same time, climate-sceptic outlets, such as the UK’s Daily Telegraph and Daily Mail, have highlighted scientific uncertainties and debates within AMOC research.
PIK’s Rahmstorf says he has noted a “whiplash effect” in the media – where the conclusions of new AMOC studies are presented as definitive. He explains:
“As scientists, we look at a whole suite of studies that exist on one topic…We look at the overall balance of evidence. Whereas the media oscillates back and forth between saying ‘this latest study proves AMOC is weakening’ [or] ‘this latest study shows it’s not weakening after all’. And then, the public, of course, is quite confused.”
He adds the media tends to err towards dramatic conclusions on AMOC:
“There are extremes in both directions. Some media articles really exaggerate [the probability and impacts of AMOC collapse] and then other media articles try to play it down as a risk. Admittedly, it is hard to get the balance right – but there are also political interests behind it as well.”
In February 2024, the AMOC received a bump of coverage after dozens of climate scientists wrote to ministers of Nordic countries to underscore the risks of AMOC collapse and the need for action to cut greenhouse gas emissions. The Guardian, Reuters, Euronews, Daily Mail, Vice News, Gizmodo and Geographical were among the publications to cover the intervention.
Also in 2024, the aforementioned Science Advances study that warned AMOC was on a “tipping course” topped Carbon Brief’s annual list of the most-covered science research of the year.
It remains unclear whether growing coverage of AMOC has focused policymakers’ minds on the question of AMOC collapse.
The topic has been debated three times in UK parliament – in 2006, 2024 and 2025, according to the parliamentary record. It was also the subject of one written question in 2024, to which a minister replied that the government had “not assessed the effect” of any slowing or collapse of the AMOC, but was “monitoring ongoing research”.
In Ireland – another country whose mild climate relies on the AMOC – official records show the issue has been debated twice, in 2024 and 2025. It has also been the subject of one written question.
In November 2025, Iceland’s climate minister Johann Pall Johannsson told Reuters that the country had officially designated the potential collapse of AMOC a national security concern.
Carbon Brief would like to thank all the scientists who helped with the preparation of this article.
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