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Evidence shows a continuing increase in the frequency and severity of global heatwaves1,2, raising concerns about the future impacts of climate change and the associated socioeconomic costs3,4. Here we develop a disaster footprint analytical framework by integrating climate, epidemiological and hybrid input–output and computable general equilibrium global trade models to estimate the midcentury socioeconomic impacts of heat stress. We consider health costs related to heat exposure, the value of heat-induced labour productivity loss and indirect losses due to economic disruptions cascading through supply chains. Here we show that the global annual incremental gross domestic product loss increases exponentially from 0.03 ± 0.01 (SSP 245)–0.05 ± 0.03 (SSP 585) percentage points during 2030–2040 to 0.05 ± 0.01–0.15 ± 0.04 percentage points during 2050–2060. By 2060, the expected global economic losses reach a total of 0.6–4.6% with losses attributed to health loss (37–45%), labour productivity loss (18–37%) and i

Anthropogenic emissions drive global-scale warming yet the temperature increase relative to pre-industrial levels is uncertain. Using 300 years of ocean mixed-layer temperature records preserved in sclerosponge carbonate skeletons, we demonstrate that industrial-era warming began in the mid-1860s, more than 80 years earlier than instrumental sea surface temperature records. The Sr/Ca palaeothermometer was calibrated against ‘modern’ (post-1963) highly correlated (R2 = 0.91) instrumental records of global sea surface temperatures, with the pre-industrial defined by nearly constant (<±0.1 °C) temperatures from 1700 to the early 1860s. Increasing ocean and land-air temperatures overlap until the late twentieth century, when the land began warming at nearly twice the rate of the surface oceans. Hotter land temperatures, together with the earlier onset of industrial-era warming, indicate that global warming was already 1.7 ± 0.1 °C above pre-industrial levels by 2020. Our result is 0.5 °C higher than IPCC estim

Une expérience de 4 mois pour repenser notre rapport au vivant grâce aux low-tech

Les forêts françaises couvrent 31% du territoire métropolitain. Elles contribuent de multiples façons au bienêtre humain (production de bois, purification de l’air et de l’eau, maintien des sols, habitat pour la biodiversité, alimentation, santé, activités récréatives, etc.) et participent aux Objectifs de Développement Durable fixés par l’ONU. En particulier, la France s’étant engagée à atteindre la neutralité carbone dès 2050, le rôle de puits et de stockage de carbone des forêts est considéré comme un élément majeur de sa Stratégie Nationale Bas Carbone (SNBC). Depuis quelques années, les forêts françaises, dont la surface n’avait cessé de croître depuis plus d’un siècle, connaissent, de façon inquiétante, une diminution de productivité, des dépérissements massifs et un risque incendie accru. Le changement climatique en cours met ainsi en péril les ressources forestières et leur contribution attendue pour préserver la biodiversité, favoriser le développement rural et la bioéconomie, renforcer la production

Permafrost and glaciers in the high Arctic form an impermeable ‘cryospheric cap’ that traps a large reservoir of subsurface methane, preventing it from reaching the atmosphere. Cryospheric vulnerability to climate warming is making releases of this methane possible. On Svalbard, where air temperatures are rising more than two times faster than the average for the Arctic, glaciers are retreating and leaving behind exposed forefields that enable rapid methane escape. Here we document how methane-rich groundwater springs have formed in recently revealed forefields of 78 land-terminating glaciers across central Svalbard, bringing deep-seated methane gas to the surface. Waters collected from these springs during February–May of 2021 and 2022 are supersaturated with methane up to 600,000 times greater than atmospheric equilibration. Spatial sampling reveals a geological dependency on the extent of methane supersaturation, with isotopic evidence of a thermogenic source. We estimate annual methane emissions from prog

Terrestrial ecosystems have taken up about 32% of the total anthropogenic CO2 emissions in the past six decades1. Large uncertainties in terrestrial carbon–climate feedbacks, however, make it difficult to predict how the land carbon sink will respond to future climate change2. Interannual variations in the atmospheric CO2 growth rate (CGR) are dominated by land–atmosphere carbon fluxes in the tropics, providing an opportunity to explore land carbon–climate interactions3–6. It is thought that variations in CGR are largely controlled by temperature7–10 but there is also evidence for a tight coupling between water availability and CGR11. Here, we use a record of global atmospheric CO2, terrestrial water storage and precipitation data to investigate changes in the interannual relationship between tropical land climate conditions and CGR under a changing climate. We find that the interannual relationship between tropical water availability and CGR became increasingly negative during 1989–2018 compared to 1960–1989

Global CO2 emissions for 2022 increased by 1.5% relative to 2021 (+7.9% and +2.0% relative to 2020 and 2019, respectively), reaching 36.1 GtCO2. These 2022 emissions consumed 13%–36% of the remaining carbon budget to limit warming to 1.5 °C, suggesting permissible emissions could be depleted within 2–7 years (67% likelihood).

Météo, climat et GIEC Quel que soit l’endroit où nous habitons, nous vivons tous avec la météo : comment les conditions de notre atmosphère évoluent au fil des minutes, des heures, des jours et des semaines. Nous vivons également tous avec le climat, c’est-à-dire, en un lieu donné, l’ensemble des caractéristiques météorologiques moyennes sur plusieurs décennies. On parle de changement climatique lorsque ces conditions moyennes commencent à se modifier, du fait de causes naturelles ou du fait des activités humaines. La hausse des températures, les variations des précipitations, l’intensification de phénomènes météorologiques extrêmes sont autant d’exemples de changements climatiques, parmi bien d’autres caractéristiques

L'empreinte environnementale du secteur numérique fait toujours l'objet de nombreux débats en France et en Europe. Du fait du manque de connaissances en sciences environnementales appliquées au secteur numérique, de nombreuses choses sont publiées et répétées sans être confrontées aux recherches récentes et vérifiées.

SI vous vous êtes déjà demandé quel était le lien entre la montée du niveau des océans et le changement climatique, nous espérons que cette planche vous aidera à y voir plus clair. Nous avons bénéficié de l'aide d'Anny Cazenave, chercheuse CNES au LEGOS (Laboratoire d'études en géophysique et océanographie spatiales), membre de l’Académie des sciences et l’un des principaux auteurs du chapitre « Élévation du niveau de la mer » du 5e rapport du Groupe d'experts intergouvernemental sur l'évolution du climat (GIEC).

Human activities are threatening to push the Earth system beyond its planetary boundaries, risking catastrophic and irreversible global environmental change. Action is urgently needed, yet well-intentioned policies designed to reduce pressure on a single boundary can lead, through economic linkages, to aggravation of other pressures. In particular, the potential policy spillovers from an increase in the global carbon price onto other critical Earth system processes has received little attention to date. To this end, we explore the global environmental effects of pricing carbon, beyond its effect on carbon emissions. We find that the case for carbon pricing globally becomes even stronger in a multi-boundary world, since it can ameliorate many other planetary pressures. It does however exacerbate certain planetary pressures, largely by stimulating additional biofuel production. When carbon pricing is allied with a biofuel policy, however, it can alleviate all planetary pressures. In the light of nine Earth Syst

Figurant comme une des obligations de l’Accord de Paris ratifié en 2016, l’éducation au changement climatique est un outil précieux pour agir à grande échelle sur les comportements et les choix des sociétés.

Le terme géo-ingénierie rassemble les différentes techniques ayant pour but de manipuler délibérément le climat à l’échelle de la planète. Selon ses promoteurs, la géo-ingénierie pourrait être une solution relativement simple et rapide à mettre en œuvre pour palier les effets du réchauffement climatique causé par les émissions de gaz à effet de serre (GES) d’origine humaine. Toutefois, la géo- ingénierie condense un ensemble de questionnements à la fois scientifiques, environnementaux, diplomatiques et éthiques.

Freshwater availability is changing worldwide. Here we quantify 34 trends in terrestrial water storage observed by the Gravity Recovery and Climate Experiment (GRACE) satellites during 2002–2016 and categorize their drivers as natural interannual variability, unsustainable groundwater consumption, climate change or combinations thereof. Several of these trends had been lacking thorough investigation and attribution, including massive changes in northwestern China and the Okavango Delta. Others are consistent with climate model predictions. This observation-based assessment of how the world’s water landscape is responding to human impacts and climate variations provides a blueprint for evaluating and predicting emerging threats to water and food security. Analysis of 2002–2016 GRACE satellite observations of terrestrial water storage reveals substantial changes in freshwater resources globally, which are driven by natural and anthropogenic climate variability and human activities.