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GLOBAL TIPPING POINTS REPORT 2025 - Summary

GLOBAL TIPPING POINTS REPORT - 2025

We report striking discoveries of numerous seafloor seeps of climate-reactive fluid and gases in the coastal Ross Sea, indicating this process may be a common phenomenon in the region. We establish the recent emergence of many of these seep features, based on their discovery in areas routinely surveyed for decades with no previous seep presence. Additionally, we highlight impacts to the local benthic ecosystem correlated to seep presence and discuss potential broader implications. With these discoveries, our understanding of Antarctic seafloor seeps shifts from them being rare phenomenon to seemingly widespread, and an important question is raised about the driver of seep emergence in the region. While the origin and underlying mechanisms of these emerging seep systems remains unknown, similar processes in the paleo-record and the Arctic have been attributed to climate-driven cryospheric change. Such a mechanism may be widespread around the Antarctic Continent, with concerning positive feedbacks that are curr

Purpose Animal emissions account for nearly 60% of total greenhouse gas emissions from the livestock sector. To estimate these emissions, the Food and Agriculture Organization of the United Nations (FAO) developed a dedicated module within the Global Livestock Environmental Assessment Model (GLEAM). Although previous studies have explored selected inputs for specific animals and emission types, a comprehensive analysis of all 92 inputs (parameters and emission factors) had not been conducted. This study aimed to identify the most influential inputs affecting ruminant emissions in GLEAM.

La première étincelle de la rédaction de cette étude a jailli lors d’un atelier organisé par l’UFAPEC intitulé : "Les parents se bougent pour le climat ! "[1] Celui-ci nous a permis de constater que certains parents s’interrogent au sujet de l’éducation aux enjeux climatiques. La lecture de précédentes études sur cette éducation à ces enjeux et leurs constats interpellants[2], que nous verrons plus loin, ont été également des éléments déclencheurs pour nous pousser à approfondir ce sujet. Afin de prolonger le questionnement des parents, nous avons fait le choix d’examiner dans cette étude si, aujourd'hui en 2025, l’éducation aux enjeux climatiques dispensée par l’école secondaire est suffisante et appropriée. Est-elle à la hauteur des enjeux climatiques que nous expliquent les scientifiques ? Quelles sont les perceptions des élèves, des parents et des enseignants à ce sujet ? Quelles sont les aspirations de ces acteurs, dans l’idéal ?

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.

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.

Why is the Trump Administration trying to kill a small space science institute in New York City? Explanation begins with Galileo’s method of scientific inquiry and ends with the role of special interest money in the United States government. Galileo improved the telescope, allowing clearer observations of the planets and the Sun. Galileo differed from his peers, as he was unafraid to challenge authority. He claimed that the world should be understood based on observations, and he spoke directly to the public. He obtained philanthropic support for his observations and openly described the conclusion that Earth was not the center of the solar system – Earth revolved around the Sun.

Canicule ! Le spectre des chaleurs extrêmes et de longue durée revient désormais à chaque été, voire dès le printemps. Voici un dossier pour mieux comprendre ces épisodes, leurs effets et le rôle du changement climatique dans l’implacable montée du thermomètre.

Identifying the socio-economic drivers behind greenhouse gas emissions is crucial to design mitigation policies. Existing studies predominantly analyze short-term CO2 emissions from fossil fuels, neglecting long-term trends and other GHGs. We examine the drivers of all greenhouse gas emissions between 1820–2050 globally and regionally. The Industrial Revolution triggered sustained emission growth worldwide—initially through fossil fuel use in industrialized economies but also as a result of agricultural expansion and deforestation. Globally, technological innovation and energy mix changes prevented 31 (17–42) Gt CO2e emissions over two centuries. Yet these gains were dwarfed by 81 (64–97) Gt CO2e resulting from economic expansion, with regional drivers diverging sharply: population growth dominated in Latin America and Sub-Saharan Africa, while rising affluence was the main driver of emissions elsewhere. Meeting climate targets now requires the carbon intensity of GDP to decline 3 times faster than the global

Young people will be exposed to a number of heatwaves that no one would have experienced in pre-industrial times. Young people will be exposed to a number of heatwaves that no one would have experienced in pre-industrial times.

We investigate the probabilities of triggering climate tipping points under five Shared Socioeconomic Pathways (SSPs) and how they are altered by including the additional carbon emissions that could arise from tipping points within the Earth's carbon cycle. The crossing of a climate tipping point at a threshold level of global mean surface temperature (threshold temperature) would commit the affected subsystem of the Earth to abrupt and largely irreversible changes with negative impacts on human well-being. However, it remains unclear which tipping points would be triggered under the different SSPs due to uncertainties in the climate sensitivity to anthropogenic greenhouse gas emissions, the threshold temperatures and timescales of climate tipping points, and the response of tipping points within the Earth's carbon cycle to global warming. We include those uncertainties in our analysis to derive probabilities of triggering for 16 previously identified climate tipping points within the Earth system.

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La France s'adapte ... Vivre à plus de 4° - La trajectoire de réchauffement de référence pour l’adaptation au changement climatique anticipe à ce jour une hausse de la température moyenne dans l’Hexagone qui atteindra +4 °C à la fin du siècle.

The ocean ecosystem is a vital component of the global carbon cycle, storing enough carbon to keep atmospheric CO2 considerably lower than it would otherwise be. However, this conception is based on simple models, neglecting the coupled land-ocean feedback. Using an interactive Earth system model, we show that the role ocean biology plays in controlling atmospheric CO2 is more complex than previously thought. Atmospheric CO2 in a new equilibrium state after the biological pump is shut down increases by more than 50% (163 ppm), lower than expected as approximately half the carbon lost from the ocean is adsorbed by the land. The abiotic ocean is less capable of taking up anthropogenic carbon due to the warmer climate, an absent biological surface pCO2 deficit and a higher Revelle factor. Prioritizing research on and preserving marine ecosystem functioning would be crucial to mitigate climate change and the risks associated with it.

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 …

Contexte: Construire une protection sociale-écologique pour une transition juste […] Nos régimes de production et de consommation déstabilisent profondément la biosphère depuis des décennies, exacerbant des vulnérabilités existantes et causant de nouveaux risques qui menacent de plus en plus la stabilité sociale et politique partout sur la planète. Ces risques, qualifiés de risques sociaux-écologiques, sont de deux types: Les risques de transformation biophysique sont liés aux effets sociaux induits par les événements extrêmes (ex.: inondations, canicules, pandémies) et les événements à évolution lente (ex.: montée du niveau des mers) résultant de la déstabilisation anthropique de la biosphère. Les risques de transition sociotechnique sont liés aux effets sociaux des réponses aux risques de transformation biophysique. Ils couvrent les effets directs des politiques environnementales (ex.: mise en place de zones à faibles émissions, primes à la rénovation énergétique des logements, taxes carbone), ainsi que leu

Previous health impact assessments of temperature-related mortality in Europe indicated that the mortality burden attributable to cold is much larger than for heat. Questions remain as to whether climate change can result in a net decrease in temperature-related mortality. In this study, we estimated how climate change could affect future heat-related and cold-related mortality in 854 European urban areas, under several climate, demographic and adaptation scenarios. We showed that, with no adaptation to heat, the increase in heat-related deaths consistently exceeds any decrease in cold-related deaths across all considered scenarios in Europe. Under the lowest mitigation and adaptation scenario (SSP3-7.0), we estimate a net death burden due to climate change increasing by 49.9% and cumulating 2,345,410 (95% confidence interval = 327,603 to 4,775,853) climate change-related deaths between 2015 and 2099. This net effect would remain positive even under high adaptation scenarios, whereby a risk attenuation of 50%

Après deux années de veille médiatique, QuotaClimat publie ce jour un rapport international révélant une augmentation alarmante des discours de désinformation climatique dans les médias d’information.

Selon Eurostat, qui publie les statistiques annuelles pour chaque pays européen, cette intensité carbone a significativement baissé en France et en Allemagne entre 2013 et 2022, mais l’industrie manufacturière française semble nettement plus carbonée que son homologue allemande. Quelle est l’origine − technologique, économique, statistique − de cet avantage allemand ?