Connect with us

Published

on

Every increment of global warming above 1.5C increases the risk of crossing key tipping points in the Earth system – even if the overshoot is only temporary, says new research.

It is well established that if global temperatures exceed 1.5C above pre-industrial levels, there is a higher risk that tipping points will be crossed.

The new study, published in Nature Communications, investigates the risk of crossing four interconnected tipping points under different “policy-relevant” future emissions scenarios.

The authors investigate the risk of tipping where warming temporarily overshoots 1.5C, but global temperatures are then brought back down using negative emissions technologies. They find that the longer the 1.5C threshold is breached, and the higher the peak temperature, the greater the risk of crossing tipping points.

The most pessimistic scenario in the study sees global warming hit 3.3C by the end of the century – in line with the climate policies of 2020 – before dropping back below 1.5C over 2100-2300. Under this pathway, there is a 45% chance of crossing tipping points by 2300, the authors say.

The authors also warn that if global temperatures rise above 2C, the additional risk of tipping for every extra increment of warming “strongly accelerates”.

For temperatures between 1.5C and 2C, the risk increases by 1-1.5% for every 0.1C increase in overshoot temperature. However, for temperatures above 2.5C, tipping risk increases to 3% per 0.1C of overshoot.

The research “underlines the need for urgent emission cuts now that do not assume substantial carbon dioxide removal later”, a scientist not involved in the study tells Carbon Brief.

Overshoot scenarios

Scientists have warned for decades that as the planet warms, there is an increasing risk that Earth systems will cross “tipping points” – critical thresholds that, if exceeded, could push a system into an entirely new state.

For example, if climate change and human-driven deforestation push the Amazon rainforest past a critical threshold, large parts of the forest could experience “dieback”. This would cause entire sections of lush rainforest to eventually shift to dry savannah.

(See Carbon Brief’s explainer on the nine tipping points that could be crossed as a result of climate change.)

The planet has already warmed by 1.3C above pre-industrial levels, and a recent study warned that five tipping elements – including the collapse of the west Antarctic ice sheet – are already within reach.

That study emphasised the importance of limiting global temperature rise to 1.5C above pre-industrial levels – in line with the 2015 Paris Agreement. It finds that warming of 1.5C would render four climate tipping elements “likely” and a further six “possible”. Meanwhile, 13 tipping elements will be either “likely” or “possible” if the planet warms by 2.6C, as expected under current climate policies.

Many of the potential pathways to limiting global temperature rise to 1.5C by 2100 see the planet initially “overshoot” the threshold before negative emissions methods are used to bring temperatures back down.

The new paper investigates 10 future warming scenarios which run to the year 2300. The authors use the PROVIDE v1.2 emission pathways, which they describe as “an extended version of the illustrative pathways identified” used in the recent sixth assessment of the Intergovernmental Panel on Climate Change (IPCC).

The original scenarios run over 2015-2300, but the authors carried them forward for another 50,000 years by following the temperature trajectory set over 2290-2300. All scenarios stabilise at 1.5C, 1C or pre-industrial temperatures. However, many include overshoots, with peak temperatures ranging from 1.57C to 3.30C.

These scenarios show a range of options for how global temperatures change under these 10 scenarios in the “medium term” – until the year 2300 – as well as in the “long term”, which runs 50,000 years into the future to see how the planet eventually stabilises.

Scenarios that reach net-zero or negative emissions by 2100 and maintain them thereafter are classified as “NZGHG emission scenarios”. The table below gives more detail on each scenario.

Scenario Overshoot peak temperature NZGHG Stabilisation temperature Scenario assumptions
CurPol-OS-1.5C 3.30C Never-NZGHG 1.5C Follows current (2020) policies until 2100, then declines
ModAct-OS-1.5C 2.69C Never-NZGHG 1.5C Follows current (2020) pledges (NDCs) until 2100, then declines
ModAct-OS-1C 2.69C Never-NZGHG 1.0C Follows current (2020) pledges (NDCs) until 2100, then declines
Ref-1p5 not defined 1.5C Reference scenario designed in temperature space
SSP5-3.4-OS 2.35C No-long-term-NZGHG 1.5C Tests system response to rapid emission changes
SSP1-1.9 1.53C No-long-term-NZGHG 1.0C Sustainable development, no long-term compensation of non-CO2 emissions
GS-NZGHG 1.70C NZGHG pre-industrial Gradual strengthening, returns warming to 1.5 °C by 2215
SP-NZGHG 1.57C NZGHG pre-industrial Broad shift towards sustainable development
Neg-NZGHG 1.67C NZGHG pre-industrial Returns warming to 1.5 °C by 2100 with heavy CDR deployment
Neg-OS-OC 1.67C NZGHG pre-industrial Returns warming to 1.5 °C by 2100 with heavy CDR deployment

Table showing the 10 scenarios used in this study. Source: Möller et al (2024).

There is quite a range between the 10 pathways.

At the high end, the “CurPol-OS-1.5C” scenario sees a continuation of the global climate policies implemented in 2020 until the year 2100, with warming peaking at 3.3C. It then sees a decline in global temperature until reaching a stabilisation of 1.5C by the year 2300.

At the low end, “Neg-OS-0C” scenario initially overshoots 1.5C to 1.67C, but then returns warming to 1.5C by 2100 using “heavy carbon dioxide removal deployment”. It also then sees average global temperatures drop to pre-industrial levels by the year 2300.

In the middle, the Ref-1p5 scenario is the only one that does not include an overshoot, instead stabilising quickly at 1.5C.

The chart below shows greenhouse gas emissions (top) and corresponding global temperature changes (bottom) associated with each scenario, identified by the different-coloured lines. The bottom chart illustrates the range in how quickly the pathways return to 1.5C or below.

Greenhouse gas emissions (top) and corresponding global temperature changes (bottom) associated with each scenario are shown in the graphics below.
Greenhouse gas emissions (top) and corresponding global temperature changes (bottom) associated with each scenario are shown in the graphics below. The table below gives more detail on each scenario. Source: Möller et al (2024).

Dr David McKay is a research impact fellow at the University of Exeter’s Global Systems Institute, who has published extensively on climate tipping points, but was not involved in this study.

He also notes that some of the scenarios shown in this study “may not be possible”, because there is debate about whether or not “the substantial carbon dioxide removal needed for large overshoots is feasible”.

Cascades

Many Earth systems are interlinked, so crossing one tipping point can increase the likelihood of crossing others. This is often described as a “domino effect” or “tipping cascade”.

The study focuses on four interconnected tipping points – collapse of the Greenland ice sheet and west Antarctic ice sheet, shutdown of the Atlantic Meridional Overturning Circulation and dieback of the Amazon rainforest.

Annika Högner is a researcher at the Potsdam Institute for Climate Impact Research (PIK) and co-lead author on the study. She tells Carbon Brief these four tipping points were chosen because they “play a significant role in the functioning of the Earth system” and “their tipping would have severe global impacts”.

The graphic below shows how the tipping points interact with each other. A “+” symbol indicates that crossing one tipping point can destabilise another. For example, a collapse of the Greenland ice sheet makes the AMOC more likely to shut down, as a result of the sudden influx of freshwater into the north Atlantic Ocean. A “±” symbol indicates that the relationship between two tipping points is uncertain.

A “-” symbol indicates that crossing one tipping point stabilises another. Högner tells Carbon Brief that the interaction between the Greenland ice sheet and AMOC is the only stabilising interaction in this study. She explains that if the AMOC were to cross a tipping point, “we [would] expect to see strong cooling in the northern hemisphere”, which will contribute to stabilising the Greenland ice sheet.

Interactions between the Greenland ice sheet collapse, west Antarctic ice sheet collapse, AMOC shutdown and Amazon dieback.
Interactions between the Greenland ice sheet collapse, west Antarctic ice sheet collapse, AMOC shutdown and Amazon dieback. A “+” indicates that crossing one tipping point destabilises another, “-” indicates that crossing one tipping point stabilises another and “±” indicates that the relationship between two tipping points is uncertain. Source: Möller et al (2024).

Earth system models “often don’t resolve tipping processes very well”, making them less suited to modelling full tipping cascades, Högner tells Carbon Brief.

Instead, she explains that the authors developed a “conceptual model”. This model does not attempt to simulate the entire Earth system, but instead just models the likelihood of tipping at different temperatures, based on existing knowledge about tipping elements from other studies.

The model takes temperature trajectories as an input and gives the state of the tipping elements after a specified time – that is, whether or not the element has tipped – as an output.

Importantly, these models include “hysteresis” – a feature of tipping systems, in which a system that has moved to a different state does not easily move back to the original state even if temperatures are reduced again.

Tipping risk

The authors use their conceptual model to calculate “tipping risk” under the 10 future warming scenarios. Högner tells Carbon Brief that tipping risk “refers to the model of all four interacting tipping elements analysed in the study”. For example, a 50% tipping risk means there is a 50% chance that at least one of the four climate elements will tip.

The top row of the graphic below shows the risk of tipping in the year 2300 (left) and in 50,000 years from now (right). Bars placed higher up indicate a greater likelihood of tipping. The dot shows the average value for each data point, while the bars show the 10-90% range.

The text on the right hand side gives likelihood levels in the calibrated language used by the IPCC: very likely means a likelihood of 90-100%, likely is 66-100%, about as likely as not is 33-66%; unlikely is 0-33%; and very unlikely is 0-10%.

The middle row shows the peak temperature under each scenario (left) and stabilisation temperature (right). The bottom row shows how long temperatures overshoot before stabilising in each scenario.

Risk of tipping in the year 2300 (left) and in 50,000 years from now (right).
Risk of tipping in the year 2300 (left) and in 50,000 years from now (right). Bars placed higher up indicate a greater likelihood of tipping. The middle row shows the peak temperature under each scenario (left) and stabilisation temperature (right). The bottom row shows how long temperatures overshoot before stabilising in each scenario. Source: Möller et al (2024).

The longer the 1.5C threshold is breached for, and the higher the peak temperature is, the greater the risk of crossing tipping points by the year 2300, the study shows.

The authors find the greatest risk of crossing tipping points in the CurPol-OS-1.5C scenario (red), which follows the climate policies of 2020 until the year 2100 and then reaches 1.5C by 2300, as this scenario has the greatest overshoot temperature and duration.

Under this scenario, there is a 45% tipping risk by 2300 and a 76% chance in 50,000 years, according to the paper.

The five pathways that do not return warming to 1.5C by the year 2100 have the greatest medium-term risks, and those with less than 0.1C overshoot have the lowest medium-term risks.

In the long-term – looking to the next 50,000 years – the authors find that stabilisation temperature is “one of the decisive variables for tipping risks”. They find that even in the Ref1p5 scenario – which sees global temperatures stabilise at 1.5C without any overshoot – there is a 50% risk of the system tipping over the next 50,000 years.

The results “illustrate that a global mean temperature increase of 1.5C is not ‘safe’ in terms of planetary stability, but must be seen as an upper limit”, the study warns.

Högner tells Carbon Brief that the paper “underlines the importance of adhering to the Paris Agreement temperature goal”.

Tessa Möller – a researcher at the International Institute for Applied Systems Analysis (IIASA) and co-lead author on the paper – tells Carbon Brief that “we have a wide portfolio of technologies available” to limit warming to 1.5C, and just need to “implement” them.

However, she also highlights the “large credibility gap” between pledges from individual countries and the policies they have actually implemented. She tells Carbon Brief that not only do we need “stronger pledges”, but it is also essential that countries follow through on them.

Long-term climate

The authors also explore the risk of each individual tipping point being crossed in different scenarios.

The plot below shows the tipping risk by 2300 under different scenarios, at different temperatures, on the left. Each colour represents one scenario. Dots positioned further to the right indicate a greater peak temperature and dots positioned higher up indicate a greater tipping risk.

The plot on the right shows the percentage change in tipping risk for every additional 0.1C of overshoot, for different peak global temperatures, for the Amazon (cross), AMOC (plus), West Antarctic ice sheet (black dot) Greenland Ice sheet (square) and overall (yellow dot).

The risk of tipping by 2300 under different scenarios, at different temperatures (left), where each colour represents one scenario.
The risk of tipping by 2300 under different scenarios, at different temperatures (left), where each colour represents one scenario. The percentage change in tipping risk for every additional 0.1C of overshoot (right), for different peak global temperatures, for the Amazon (cross), AMOC (plus), West Antarctic ice sheet (black dot) Greenland Ice sheet (square) and overall (yellow dot). Source: Möller et al (2024).

The authors find that AMOC collapse and Amazon dieback would likely be the first components to tip. This could be in the next 15-300 years and 50-200 years, respectively, depending on the scenario, they find.

Meanwhile, the Greenland and west Antarctic ice sheets have tipping timescales of 1,000-15,000 years and 500-13,000 years, respectively.

However, they note that as temperatures increase, the relative risk of each element tipping changes. The graph shows that while AMOC is the main driver of tipping risk at lower temperatures, the Amazon becomes the main driver once global temperatures exceed 2C.

Finally, they find that as global temperatures rise, the risk of tipping accelerates. Overall, tipping risk increases by 1-1.5% per 0.1C increase in overshoot temperature, for temperatures below 2C, according to the study. However, above 2.5C, tipping risk increases to 3% per 0.1C increase overshoot.

McKay notes that there are some limitations in the study. For example, he notes that the paper “has to rely on tipping threshold and timescale estimates with often wide ranges and sometimes low confidence, while tipping interaction estimates are based on dated expert judgement”.

However, he adds:

“This work makes it clear that every fraction of warming increases the chance of tipping points, even if global temperature subsequently falls, and underlines the need for urgent emission cuts now that do not assume substantial carbon dioxide removal later.”

The post ‘Every 0.1C’ of overshoot above 1.5C increases risk of crossing tipping points appeared first on Carbon Brief.

‘Every 0.1C’ of overshoot above 1.5C increases risk of crossing tipping points

Continue Reading

Climate Change

European, island states seek clear future for global roadmap to cut fossil fuels

Published

on

The global roadmap on transitioning away from fossil fuels now being developed should be a “continuing conversation” which is part of UN climate talks, not just a one-off report, several governments told the Brazilian COP30 Presidency on Friday in Bonn.

During a 90-minute exchange of views at the annual mid-year climate talks in Germany, several European governments and the Marshall Islands said the roadmap that Brazil is due to finish by November should be incorporated into the official negotiations.

Any such push is likely to be resisted by nations whose economies are reliant on fossil fuel production. While Russia did not speak on Friday, it has said in earlier written submissions that the roadmap should not be referenced in any document approved by governments at UN climate talks.

At COP30 last year, Brazil tried to get governments to agree to produce a roadmap on how to transition away from fossil fuels but the proposal did not win consensus, with major nations like Saudi Arabia and Russia opposed.

Feedback in Bonn

To save the day, Brazil’s COP30 president André Aranha Corrêa do Lago promised at the closing plenary in Belem to draw up a voluntary roadmap in consultation with interested governments. Over 20 countries have officially submitted their opinions on this roadmap and, in Bonn on Friday, Corrêa do Lago sought their views – and those of civil society – in person after the presidency presented its findings so far.

The roadmap will also incorporate outcomes from the first global conference on transitioning away from fossil fuels held in Santa Marta, Colombia, in April and attended by around 60 countries.

A negotiator for the Marshall Islands told Friday’s meeting that at COP31 this year all governments should “welcome the collaborative effort behind the roadmap and the Santa Marta conference and for this work to be taken on to COP32 and beyond”.

    A spokesperson for Switzerland said on behalf of a group of nations which includes South Korea and Mexico that the roadmap must be a “sustained process, not a one-off report” and “we would welcome an ongoing platform for dialogue, for learning and cooperation including among fossil-fuel production countries”.

    “We expect more than a document, rather a process whereby we come together to develop concrete steps, recommendations and tools to prepare for the transitions,” she said, calling on the COP31 co-presidents Australia and Turkiye and COP32 host Ethiopia to “take up the leadership” for implementing the roadmap”.

    Global stocktake response

    France’s negotiator said the roadmap “is a process and we will need continuing discussions” as “implementation needs time”, while the UK called for a “continuing conversation, including as we head towards the second [global stocktake]”. 

    The global stocktake (GST) is an official five-yearly report into how the world’s governments are doing on their Paris Agreement goal to limit global warming to 1.5C above pre-industrial temperatures.

    The second stocktake will be published in 2028 and governments are likely to negotiate a response to it, which could include new commitments to reduce emissions, at COP33 that year. The response to the first global stocktake included the landmark COP28 commitment to transitioning away from fossil fuels in energy systems.

    Activists and Indigenous people take part in a Stop EACOP campaign protest against fossil fuels during the UN Climate Change Conference (COP30) in Belem, Brazil, November 13, 2025. REUTERS/Adriano Machado

    Activists and Indigenous people take part in a Stop EACOP campaign protest against fossil fuels during the UN Climate Change Conference (COP30) in Belem, Brazil, November 13, 2025. REUTERS/Adriano Machado

    “Even though it’s not a formal part of the negotiation agenda, the roadmap can be a key input for the entire information-gathering phase of the second GST,” Enrique Maurtua Konstantinidis, an independent climate policy consultant, explained to Climate Home News. 

    “The key is for countries not to focus the discussion on defending the roadmap itself, but rather on its content, which is what truly matters,” he added.

    At the Bonn event, civil society organisations also supported continuing the roadmap inside the formal climate process.

    Natalie Jones, policy adviser for the International Institute for Sustainable Development, told Climate Home News the roadmap should be “an ongoing dialogue where countries can exchange their experiences, best practices and continue implementing the [transitioning away from fossil fuels] consensus”.

    Russian resistance

    But economies reliant on fossil fuel production are likely to oppose incorporating the roadmap into negotiations in Bonn and at COP summits. Russia’s written submission to Brazil’s consultation says the roadmap was not agreed by governments at COP30.

    It says such work should therefore take place on the margins of the UNFCCC process, adding that “ the inclusion of any references to the “Roadmap” in the agenda or in official or informal documents” at Bonn or COP “would constitute a deviation from previously agreed consensus outcomes”.

    Other major oil and gas producers like Saudi Arabia have not made written or spoken submissions and the US, as it has left the Paris Agreement, is not involved in discussions. But countries other than Russia are likely to resist incorporating the roadmap into official talks.

    The UN climate process needs ambition – the law demands it

    The submission by Japan, which is not a major producer of fossil fuels but consumes them from overseas, suggests nervousness about the roadmap. It asks Brazil for clarity on how the roadmap is “envisaged to be utilised” and argues that as many countries continue to rely on fossil fuels for electricity, a full and fast shift to “full decarbonisation” is “challenging.

    After Friday’s event, Corrêa do Lago told Climate Home News that “the suggestions and the key milestones of the roadmap are not clear yet”. He added that the next step for the COP30 presidency will be to “sit down in July and August to really prepare” the content.

    The veteran Brazilian diplomat added that the roadmap will have a section on the challenges of the transition and another section on solutions.

    National fossil fuel roadmaps

    Brazil, as COP30 president, is drawing up the global roadmap but its leader Lula da Silva has also ordered his officials to draw up a national roadmap. 

    In April, France became the first and so far only nation to produce a roadmap, which amalgamated different existing energy and decarbonisation plans and targets. Colombia is reportedly drawing up a roadmap too, based on a draft document by academics.

    On Friday, a coalition of nearly 100 civil society organisations called on the COP31 co-presidents Australia and Türkiye to both come up with national roadmaps in order to “lead by example”. Türkiye produces about a third of its electricity from coal, while Australia is the world’s third-largest fossil fuel exporter, the NGOs said.

    But in the Brazil-led consultation meeting, a Norwegian negotiator downplayed the importance of separate national roadmaps for transitioning away from fossil fuels.

    While they can “have a supporting role”, the official said countries’ nationally determined contributions (NDCs) “must remain the primary vehicle for driving global climate transition.”

    NDCs are climate plans, usually containing emissions reduction targets, which the Paris Agreement states governments must update with higher ambition every five years. 

    The post European, island states seek clear future for global roadmap to cut fossil fuels appeared first on Climate Home News.

    https://www.climatechangenews.com/2026/06/12/european-island-states-seek-clear-future-for-global-roadmap-to-cut-fossil-fuels/

    Continue Reading

    Climate Change

    Hoover Dam Approaches a Hydropower Cliff

    Published

    on

    Big cuts in generating capacity are coming as the Colorado River struggles to meet demand.

    Some day in the next 12 months—maybe in late August, maybe not until next spring— Lake Mead will drop below the critical threshold of 1,035 feet above sea level.

    Hoover Dam Approaches a Hydropower Cliff

    Continue Reading

    Climate Change

    DeBriefed 12 June 2026: El Niño begins | COP31 hosts eye electrification | Atlantic current monitoring at risk

    Published

    on

    Welcome to Carbon Brief’s DeBriefed.
    An essential guide to the week’s key developments relating to climate change.

    This week

    El Niño begins

    ‘DOMINO WEATHER’: The natural weather phenomenon El Niño, which can raise global heat and “bring domino weather effects across the planet”, is now underway, the US National Oceanic and Atmospheric Administration (NOAA) declared on Thursday, reported the Washington Post. The Japanese Meteorological Administration also identified the start of El Niño on Wednesday, said Bloomberg. According to the Japanese weather agency, the event is “expected to intensify in the coming months and become very strong later in the year, persisting into at least December”, reported the outlet.

    ‘SUPER EVENT’: BBC News reported that “many forecasts suggest this could end up as a so-called ‘super’ El Niño” and be “among the strongest ever recorded”. It added: “Coming on top of decades of human-caused warming, it could bring another record-hot year – most likely in 2027 – with disruption to weather, food supplies and economies running well into that year.”

    COP31 hosts eye electrification

    ‘35 BY 35’: COP31 hosts Turkey and Australia have called for countries to support a target of electrifying 35% of global energy use by 2035, reported Politico. Speaking at climate talks in Bonn, Germany, Turkish minister Murat Kurum said that electrification would be a “flagship priority” at the COP31 summit, noted the publication. Kurum added that “electrifying daily life, from transport to buildings and industry” could “protect families and businesses from volatile energy markets”, said the outlet.

    WASTE AND BUILDINGS: Climate Home News reported that electrification was one of three priorities unveiled by the COP31 hosts, with the other two being waste and buildings. On buildings, the COP31 hosts “quietly overhauled [their] goal”, Climate Home News said. It reported: “An initial press statement on Monday set out a target ‘to achieve at least a 25% increase in energy efficiency in buildings by 2035’. But…on Tuesday, that was replaced with a different goal to ‘reduce energy consumption intensity in the building sector by at least 25% by 2035’.”

    ‘HARDEST’ CHALLENGE: Elsewhere in Bonn, UN climate chief Simon Stiell said “governments must stop revisiting climate commitments and start delivering on them”, South Africa’s Mail and Guardian reported. It quoted Stiell as saying: “Tackling the global climate crisis is the hardest but most important thing humanity has ever tried to do together…We are not yet where we need to be. But we are somewhere we have never been before.”

    Around the world

    • ETS EXTRA: The EU has agreed “stronger” price controls on “ETS2”, its planned trading system for heating and transport emissions, according to Reuters.
    • OCEAN STRESS: The rate of sea level rise has doubled in 10 years amid “severe and accelerating” pressures on oceans, said a UN report covered by Time.
    • CLIMATE MIGRANTS: Donald Trump’s “immigration crackdown is largely targeting people from the countries most vulnerable to displacement from climate-driven disasters”, according to Guardian analysis.
    • ULTRA-RICH: Investments by the world’s ultra-rich in 2022 are linked to nearly $1tn in climate damages, according to a Greenpeace Africa analysis covered by BusinessGreen.

    Two

    The number of bidders for Trump’s auction for drilling rights in an Arctic wildlife refuge, with big oil companies “sitting out the sale”, reported Bloomberg.


    Latest climate research

    • As the Arctic warms, increased iceberg activity could “reshape” deep-sea habitats and “elevate” navigational hazards as maritime traffic expands | Nature
    • Around 11% of the population of the world’s “rarest great ape”, the Tapanuli orangutan, is estimated to have perished in an extreme rainfall event in Indonesia in 2025 | Current Biology
    • Canada’s forests are shifting from a carbon sink to a carbon source, due to “wildfires disturbances” | Global Change Biology

    (For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Monday, Tuesday, Wednesday, Thursday and Friday.)

    Captured

    Solar power has overtaken gas in Asia to become the region’s third largest electricity source behind coal and hydropower, according to Carbon Brief analysis of data from the thinktank Ember. Solar became the third largest electricity source for Asia on an annual basis in April 2026, according to the analysis. In the year to April 2026, solar generated 1,727 terawatt hours (TWh), while gas generated 1,711TWh, it added.

    Spotlight

    Atlantic current monitoring at risk

    This week, Carbon Brief reports on how Trump plans could disrupt efforts to track a major ocean current.

    The Irminger Sea, a patch of frigid ocean east of Greenland, plays an outsized role in the Earth’s climate.

    Here, surface water that has travelled thousands of kilometres from the tropics grows cold and dense enough to sink to the ocean’s depths – a transformation that must occur for the water to begin a long journey back to the southern hemisphere.

    This makes the Irminger Sea an “action centre” for the mighty Atlantic Meridional Overturning Circulation (AMOC), the vast system of ocean currents that keeps temperatures in Europe mild.

    Last week, the US government announced plans to dismantle ocean moorings installed in the Irminger Sea which, among other things, collect data on the health of the AMOC.

    This came as part of a programme to “descope” the Ocean Observatories Initiative, a $368m network of ocean sensors installed in the Pacific and Atlantic oceans.

    Two of the moorings earmarked for removal in the Irminger Sea form part of an internationally funded, trans-Atlantic AMOC monitoring array, known as OSNAP, that stretches from Canada to Scotland.

    Experts told Carbon Brief the move by the Trump administration highlights the vulnerability of AMOC observation systems around the world. These deep-sea moorings – scattered across the Atlantic – collect real-time data on, among other things, ocean current, temperature, pressure and biochemistry.

    Prof Penny Holliday, chief scientific officer of the UK National Oceanography Centre, told Carbon Brief that the OSNAP array, as well as the RAPID array at 26N, are “entirely dependent” on research grants that have to be “continually reapplied for”.

    “Funding is perilous all the time,” she said.

    A report prepared last month by scientists for Nordic ministers exploring the security of funding for AMOC observing systems warned that RAPID and OSNAP were in “critical condition” and faced “material exposure over an 18-month horizon”. Meanwhile, other key basin-wide and global components of the global AMOC observing system were rated as “at risk”.

    It is not just US funding that is uncertain. The report notes, for example, that the five-yearly funding the UK provides to RAPID and OSNAP is “at risk from 2027 due to year-on-year budget reductions” at the Natural Environmental Research Council.

    (RAPID is funded by the US and UK, whereas OSNAP is backed by five different countries, with the US contributing half of the total financial support.)

    Report co-author Dr Femke de Jong from the Royal Netherlands Institute for Sea Research told Carbon Brief that “continued AMOC observations” are under pressure in “multiple countries”. She said:

    “While the risk of a declining AMOC to society is starting to be recognised, there is not yet a system or institution in place to guarantee a way to monitor it.”

    AMOC monitoring arrays are still in their infancy – RAPID, the oldest, was launched in 2004. Two decades of data captured so far shows that the AMOC is slowing down. However, scientists will need many more years of data to be able to confidently link the decline to climate change, rather than natural variability in the ocean.

    NOC’s Holliday points to the disconnect between scientific and funder timelines:

    “The timescale of observations needed in order to be able to detect a climate change signal from the very naturally variable ocean is around 40-60 years…. [And yet], in the Netherlands, they have to apply for a new grant for their ocean moorings every two years. They are going to have to do that for 40 years.

    “This is a very inefficient way of getting funding for what should be critical infrastructure.”

    This spotlight first appeared in Cited, Carbon Brief’s new fortnightly newsletter focused on climate research. Sign up for free.

    Watch, read, listen

    ‘BEYOND GROWTH’: A group of economists set out a “roadmap for eradicating poverty beyond growth” in the Guardian.

    OIL CAMPAIGN: Politico reported on how “oil industry allies” are campaigning against attribution science, including by working to discredit a US National Academies report that “will examine research into the ways corporate climate pollution is intensifying natural disasters”.

    ‘FIGHT BACK’: For the Apocalyptic Optimist podcast, Dr Dana Fisher spoke to historian and author Dr Naomi Oreskes about how to “fight back” against climate misinformation.

    Coming up

    Pick of the jobs

    DeBriefed is edited by Daisy Dunne. Please send any tips or feedback to debriefed@carbonbrief.org.

    This is an online version of Carbon Brief’s weekly DeBriefed email newsletter. Subscribe for free here.

    The post DeBriefed 12 June 2026: El Niño begins | COP31 hosts eye electrification | Atlantic current monitoring at risk appeared first on Carbon Brief.

    DeBriefed 12 June 2026: El Niño begins | COP31 hosts eye electrification | Atlantic current monitoring at risk

    Continue Reading

    Trending

    Copyright © 2022 BreakingClimateChange.com