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The Atlantic meridional overturning circulation (AMOC) is an important tipping element in the climate system. There is a large uncertainty whether the AMOC will start to collapse during the century under future climate change, as this requires long climate model simulations which are not always available. Here, we analyze targeted climate model simulations done with the Community Earth System Model (CESM) with the aim to develop a physics-based indicator for the onset of an AMOC tipping event. This indicator is diagnosed from the surface buoyancy fluxes over the North Atlantic Ocean and is performing successfully under quasi-equilibrium freshwater forcing, freshwater pulse forcing, climate change scenarios, and for different climate models. An analysis consisting of 25 different climate models shows that the AMOC could begin to collapse by 2063 (from 2026 to 2095, to percentiles) under an intermediate emission scenario (SSP2-4.5), or by 2055 (from 2023 to 2076, to percentiles) under a high-end emission scenar

This article examines the technocentric bias that characterizes climate mitigation literature, focusing on the reports of the IPCC's Working Group III. This bias stems from structural features of the scientific field that prioritizes innovation, leading to the overrepresentation of technological solutions in climate research. Funding mechanisms further reinforce this tendency by incentivizing collaboration with industrial R&D, creating a self-reinforcing loop in which scientific authority and industrial interests converge. The IPCC's institutional positioning—as a policy-relevant yet politically cautious body—amplifies this dynamic by favoring allegedly “cost-effective” technological pathways that lack practical feasibility.

Passing 1.5ºC is now inevitable. Overshoot scenarios tell us that we can relatively safely pass this level but then bring temperatures back down again, but how realistic are they, and how safe?

Climate sensitivity is substantially higher than IPCC’s best estimate (3°C for doubled CO2), a conclusion we reach with greater than 99 percent confidence. We also show that global climate forcing by aerosols became stronger (increasingly negative) during 1970-2005, unlike IPCC’s best estimate of aerosol forcing. High confidence in these conclusions is based on a broad analysis approach. IPCC’s underestimates of climate sensitivity and aerosol cooling follow from their disproportionate emphasis on global climate modeling, an approach that will not yield timely, reliable, policy advice.

The constant deluge of bad news about rising global temperatures and their impacts can make it feel like the world is ending. Is it?

C’est une tendance qui ne faiblit pas sur les réseaux sociaux. Face à la crise écologique, des centaines de jeunes témoignent de leur pessimisme quant à notre capacité à redresser la barre : on les appelle les "climate doomers". Résultat d’une éco-anxiété grandissante, ce phénomène participe à freiner l’action climatique.

For decades, the surface of the polar Southern Ocean (south of 50°S) has been freshening—an expected response to a warming climate. This freshening enhanced upper-ocean stratification, reducing the upward transport of subsurface heat and possibly contributing to sea ice expansion. It also limited the formation of open-ocean polynyas. Using satellite observations, we reveal a marked increase in surface salinity across the circumpolar Southern Ocean since 2015. This shift has weakened upper-ocean stratification, coinciding with a dramatic decline in Antarctic sea ice coverage. Additionally, rising salinity facilitated the reemergence of the Maud Rise polynya in the Weddell Sea, a phenomenon last observed in the mid-1970s.

Real world measurements of how much extra heat the Earth is trapping are well beyond most climate models. That’s a real problem.

Les financements aux industries du pétrole et du gaz repartent de plus belle. Le rapport Banking on climate chaos, signé par huit ONG, estime à près de 900 milliards de dollars les financements octroyés en 2024 par 65 banques aux industriels du secteur, en augmentation de 23%. Le backlash contre la finance durable n’est pas étranger à ce nouvel appétit de la finance pour les hydrocarbures.

Mark Lynas has spent decades pushing for action on climate emissions but now says nuclear war is even greater threat Climate breakdown is usually held up as the biggest, most urgent threat humans pose to the future of the planet today. But what if there was another, greater, human-made threat that could snuff out not only human civilisation, but practically the entire biosphere, in the blink of an eye?

Despite mounting evidence of global warming’s costs, the Trump administration has made multiple moves to avoid tracking climate-related economics.

On 21 April 2019, I was on Waterloo Bridge in London with my younger siblings. Around us were planters full of flowers where there were once cars, and people singing. This was the spring iteration of Extinction Rebellion, when four bridges in London were held by protesters. My siblings, then 14, had been going out on school strike inspired by Greta Thunberg, and wanted to see her speak.

Societies increasingly rely on scientists to guide decisions in times of uncertainty, from pandemic outbreaks to the rise of artificial intelligence. Addressing climate change is no different. For governments wanting to introduce ambitious climate policies, public trust in climate scientists is pivotal, because it can determine whether voters support or resist those efforts.

The nation’s top banks are quietly advising their clients on how to build a financial life raft — or perhaps life yacht — from the wreckage of runaway climate change. Make no mistake: The forecasts coming from Wall Street’s leading financial institutions are bleak. But they also point their clients to potential profit-making opportunities from the havoc spreading across the planet, writes Corbin Hiar.

Climate change is driving rising global temperatures, ecological degradation, and widespread human suffering. Yet, as a collective, humanity has failed to implement sufficient changes to mitigate these threats. This paper introduces the concept of “global narcissism” as a speculative lens to analyze the psychological barriers to climate action. By examining different levels of narcissism and their manifestations in human responses to climate change, this framework highlights key obstacles to meaningful action. While humanity is diverse, and lived experiences vary greatly, this perspective offers a way to discuss patterns of response and resistance. A central challenge lies in humanity’s difficulty in recognizing its symbiotic relationship with the non-human world. Through the metaphor of “global narcissism” this paper explores how humanity’s response to ecological crisis mirrors narcissistic defense mechanisms and suggests a collapse is taking place. This framework provides insights into how psychological int

Springtails illustrate in new research how global warning and antibiotic resistance creates synergistic effects: warming increases pesticide toxicity, triggering antibiotic resistance which spreads through horizontal gene transfer and predation.

A superpower in the fight against global heating is hiding in plain sight. It turns out that the overwhelming majority of people in the world – between 80% and 89%, according to a growing number of peer-reviewed scientific studies – want their governments to take stronger climate action.

Morgan Stanley, JPMorgan and an international banking group have quietly concluded that climate change will likely exceed the Paris Agreement’s 2 degree goal.Top Wall Street institutions are preparing for a severe future of global warming that blows past the temperature limits agreed to by more than 190 nations a decade ago, industry documents show.

Antarctica's remote and mysterious current has a profound influence on the climate, food systems and Antarctic ecosystems. Can we stop it weakening by 2050?

The Antarctic Circumpolar Current (ACC) is the world's strongest ocean current and plays a disproportionate role in the climate system due to its role as a conduit for major ocean basins. This current system is linked to the ocean's vertical overturning circulation, and is thus pivotal to the uptake of heat and CO2 in the ocean. The strength of the ACC has varied substantially across warm and cold climates in Earth's past, but the exact dynamical drivers of this change remain elusive. This is in part because ocean models have historically been unable to adequately resolve the small-scale processes that control current strength. Here, we assess a global ocean model simulation which resolves such processes to diagnose the impact of changing thermal, haline and wind conditions on the strength of the ACC. Our results show that, by 2050, the strength of the ACC declines by ∼20% for a high-emissions scenario. This decline is driven by meltwater from ice shelves around Antarctica, which is exported to lower latit

The Atlantic Meridional Overturning Circulation (AMOC), vital for northwards heat transport in the Atlantic Ocean, is projected to weaken owing to global warming1, with significant global climate impacts2. However, the extent of AMOC weakening is uncertain with wide variation a …

One of the world’s most climate-ambitious governments is about to fall, replaced by a likely chancellor who says green policy went too far.

Shifting responsibility to consumers minimises the role of energy industry and policymakers, University of Sydney research suggests

On the topic of climate and carbon reduction commitments, corporations like Google, Microsoft, and Shell once positioned themselves as leaders in sustainability, setting ambitious net-zero goals to align with global environmental efforts. However, the rapid rise of energy-hungry artificial intelligence is forcing these companies to reconsider—or even abandon—these commitments as they struggle to balance environmental responsibility and making money from new tech.

Sea ice extent for the Arctic overall as of mid-December is at the lowest for this point in the season in the entire satellite era record (since autumn 1978) Whether this is a transient low extent or not, expanded open water now, with the winter solstice upon us, means that there’s less time for ice, once it forms, to thicken up before the spring melt commences in a few months.

As the world’s largest gathering of Earth and space scientists swarmed a Washington venue last week, the packed halls have been permeated by an air of anxiety and even dread over a new Donald Trump presidency that might worsen what has been a bruising few years for science.

The climate and ecological crisis poses an unprecedented challenge, with scientists playing a critical role in how society understands and responds. This study examined how 27 environmentally concerned scientists from 11 countries construct the future in the context of climate change, applying a critical discursive psychology analysis. The degree to which the future is constructed as predetermined or transformable impacts both the urgency and scope of proposed actions. ...

Trump could reverse the nation’s progress on climate change, but rolling back the Biden administration’s significant climate successes could be a low, slow and difficult process...

Global warming has already caused the Arctic to release more climate-warming methane—but exactly how much will depend closely on the actions we take to halt climate change.

A Trump presidency can delay, but not stop, the global transition to renewable energy, but it may more effectively stymie progress than during his first term.