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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