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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

In a rapidly changing climate, evidence-based decision-making benefits from up-to-date and timely information. Here we compile monitoring datasets (published at https://doi.org/10.5281/zenodo.15639576; Smith et al., 2025a) to produce updated estimates for key indicators of the state of the climate system: net emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radiative forcing, the Earth's energy imbalance, surface temperature changes, warming attributed to human activities, the remaining carbon budget, and estimates of global temperature extremes. This year, we additionally include indicators for sea-level rise and land precipitation change. We follow methods as closely as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One report.

An international group of researchers has produced a third update to key indicators of the state of the climate system set out in the IPCC AR6 assessment, building on previous editions in 2023 and 2024. Forster et al. (2025) assess emissions, concentrations, temperatures, energy transfers, radiation balances, and the role of human activity and conclude that, while natural climate variability also played a role, the record observed temperatures in 2024 were dominated by human activity and the remaining carbon budget for 1.5° C is smaller than ever.

Recent simulations using the Community Earth System Model (CESM) indicate that a tipping event of the Atlantic Meridional Overturning Circulation (AMOC) would cause Europe to cool by several degrees. This AMOC tipping event was found under constant pre-industrial greenhouse gas forcing, while global warming likely limits this AMOC-induced cooling response. Here, we quantify the European temperature responses under different AMOC regimes and climate change scenarios. A strongly reduced AMOC state and intermediate global warming (C, Representative Concentration Pathway 4.5) has a profound cooling effect on Northwestern Europe with more intense cold extremes. The largest temperature responses are found during the winter months and these responses are strongly influenced by the North Atlantic sea-ice extent. Enhanced North Atlantic storm track activity under an AMOC collapse results in substantially larger day-to-day temperature fluctuations. We conclude that the (far) future European temperatures are dependent o

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.

Earth’s albedo (reflectivity) declined over the 25 years of precise satellite data, with the decline so large that this change must be mainly reduced reflection of sunlight by clouds. Part of the cloud change is caused by reduction of human-made atmospheric aerosols, which act as condensation nuclei for cloud formation, but most of the cloud change is cloud feedback that occurs with global warming. The observed albedo change proves that clouds provide a large, amplifying, climate feedback. This large cloud feedback confirms high climate sensitivity, consistent with paleoclimate data and with the rate of global warming in the past century.

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

Paper in Nature Climate Change journal reveals major role wealthy emitters play in driving climate extremes. The world’s wealthiest 10% are responsible for two-thirds of global heating since 1990, driving droughts and heatwaves in the poorest parts of the world, according to a study.

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.

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.

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 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

Climate change will set the parameters of our post-Princeton lives. The fires that devastated the Palisades earlier this month were, as our nation’s exasperated and exhausted climate scientists continue to remind us, only harbingers of the floods, tornados, and heatwaves to come. Global warming is surpassing the climate models that scientists built in the 2010s and early 2020s that already forecasted a borderline-apocalyptic future. Undoubtedly, by the time current Princeton students reach middle age, they will have witnessed a slew of societal structures sag — or collapse entirely — under the weight of extreme weather events and ever-worsening ecological decline.

Human-caused climate change increased the likelihood and intensity of the hot, dry and windy conditions that fanned the flames of the recent devastating Southern California wildfires, a scientific study found. But the myriad of causes that go into the still smoldering fires are complex, so the level of global warming's fingerprints on weeks of burning appears relatively small compared to previous studies of killer heat waves, floods and droughts by the international team at World Weather Attribution. Tuesday's report, too rapid for peer-review yet, found global warming boosted the likelihood of high fire weather conditions in this month's fires by 35% and its intensity by 6%.

Jean-Marc Jancovici, ingénieur spécialiste du changement climatique et président du think tank Shift Project, alerte sur des plans d'adaptation encore trop peu contraignants.

High-level policy discussions have built momentum for “food system transformation” that would help farmers address the climate crisis.

Annually updated, IPCC AR6 consistent indicators of human-induced global warming, greenhouse gas emissions, and the remaining global carbon budget.

Abstract. Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC). Evidence-based decision-making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5–10 years, creating potential for an information gap between report cycles. We follow methods as close as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One (WGI) report. We compile monitoring datasets to produce estimates for key climate indicators related to forcing of the climate system: emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radiative forcing, the Earth's energy imbalance, surface temperature changes, warming attributed to human activit

Over the past 50 years, humans have extracted the Earth’s groundwater stocks at a steep rate, largely to fuel global agro-economic development. Given society’s growing reliance on groundwater, we explore ‘peak water limits’ to investigate whether, when and where humanity might reach peak groundwater extraction. Using an integrated global model of the coupled human–Earth system, we simulate groundwater withdrawals across 235 water basins under 900 future scenarios of global change over the twenty-first century. Here we find that global non-renewable groundwater withdrawals exhibit a distinct peak-and-decline signature, comparable to historical observations of other depletable resources (for example, minerals), in nearly all (98%) scenarios, peaking on average at 625 km3 yr−1 around mid-century, followed by a decline through 2100. The peak and decline occur in about one-third (82) of basins, including 21 that may have already peaked, exposing about half (44%) of the global population to groundwater stress. Most

Global projections of macroeconomic climate-change damages typically consider impacts from average annual and national temperatures over long time horizons1–6. Here we use recent empirical findings from more than 1,600 regions worldwide over the past 40 years to project sub-national damages from temperature and precipitation, including daily variability and extremes7,8. Using an empirical approach that provides a robust lower bound on the persistence of impacts on economic growth, we find that the world economy is committed to an income reduction of 19% within the next 26 years independent of future emission choices (relative to a baseline without climate impacts, likely range of 11–29% accounting for physical climate and empirical uncertainty). These damages already outweigh the mitigation costs required to limit global warming to 2 °C by sixfold over this near-term time frame and thereafter diverge strongly dependent on emission choices. Committed damages arise predominantly through changes in average tempe

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

Mitigating climate change necessitates global cooperation, yet global data on individuals’ willingness to act remain scarce. In this study, we conducted a representative survey across 125 countries, interviewing nearly 130,000 individuals. Our findings reveal widespread support for climate action. Notably, 69% of the global population expresses a willingness to contribute 1% of their personal income, 86% endorse pro-climate social norms and 89% demand intensified political action. Countries facing heightened vulnerability to climate change show a particularly high willingness to contribute. Despite these encouraging statistics, we document that the world is in a state of pluralistic ignorance, wherein individuals around the globe systematically underestimate the willingness of their fellow citizens to act. This perception gap, combined with individuals showing conditionally cooperative behaviour, poses challenges to further climate action. Therefore, raising awareness about the broad global support for climat

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

As we mark 100 days until the COP28 UN climate summit, the urgency of addressing the climate crisis has never been more palpable. Global failures to mitigate emissions and adapt to the impacts continue to wreak havoc on the planet, and we’re seeing this in a range of ways. Unprecedented extreme weather events have occurred with frightening regularity in 2023. In March, over 500 people lost their lives when Cyclone Freddy struck Malawi. Last month, flooding in the Philippines caused by Typhoons Doksuri and Khanun displaced more than 300,000 people, and the recent wildfires that ravaged Hawaii – in part exacerbated by climate change – continue to make for distressing headlines. This list is likely to become even longer by the end of the year, when COP28 gets underway in the United Arab Emirates (UAE).

Een internationaal team van wetenschappers werkt aan een systeem dat de achtjaarlijkse rapporten van het VN-klimaatpanel aanvult met een actuele stand van zaken per jaar. Klimaatexpert Piers Forster van de Universiteit van Leeds legt uit waarom dat zo belangrijk is, en wat de laatste bevindingen zijn.

Abstract. Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC), including the first global stocktake under the Paris Agreement that will conclude at COP28 in December 2023. Evidence-based decision-making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5–10 years, creating potential for an information gap between report cycles. We follow methods as close as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One (WGI) report. We compile monitoring datasets to produce estimates for key climate indicators related to forcing of the climate system: emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radia

Cette première partie de conférence traite de l'histoire de nos sociétés de consommation à la mode occidentale grâce aux énergies modernes esssentiellement f...

Concerns about climate change shrank across the world last year, with fewer than half of those questioned in a new survey believing it posed a “very serious threat” to their countries over the next 20 years.

L’introduction du concept d’Anthropocène – sous ce terme et avec les arguments scientifiques de la recherche contemporaine, en glaciologie et paléoclimatologie notamment – se situe significativement dans le cadre du Programme International Géosphère-Biosphère (IGBP), c’est-à-dire au cœur de la coopération scientifique internationale mobilisée autour du fameux « Global Change » : expression d’origine américaine (proche des « recherches biosphériques » et atmosphériques de la Nasa) qui désigne la problématique des transformations environnementales, naturelles et anthropogéniques (d’origine humaine), à l’échelle du Globe, notre « globe terraqué » (composé de terre et d’eau), comme disait les naturalistes et natural philosophers de l’Europe chrétienne classique, ou si l’on préfère préindustrielle et encore néolithique. ...

Increasing risks posed by climate change are causing rare extreme events that can kill more than 10 million people or lead to damages of $10 trillion-plus, posing threats of total societal collapse, a UN report finds.

Food supply expert paints grim global picture hunger 05.23.2022 By Arvin Donley NEW YORK, NEW YORK, US — Global wheat inventories currently stand at about 10 weeks of global consumption, a food supply expert said during a special meeting of the United Nations Security Council on May 19. Sara Menker, chief executive officer of Gro Intelligence, an organization that gathers and analyzes global food and agricultural data, said she disputes official government agency estimates that put global wheat inventories at 33% of annual consumption, countering inventories are closer to 20%. “It is important to note that the lowest grain inventory levels the world has ever seen are now occurring while access to fertilizers is highly constrained, and drought in wheat growing regions around the world is the most extreme it’s been in over 20 years,” Menker said. “Similar inventory concerns also apply to corn and other grains. Government estimates are not adding up.” Menker told the security council that while much of the blame

Long before the current political divide over climate change, and even before the U.S. Civil War (1861-1865), an American scientist named Eunice Foote documented the underlying cause of today’s climate change crisis. The year was 1856. Foote’s brief scientific paper was the first to describe the extraordinary power of carbon dioxide gas to absorb heat – the driving force of global warming. Carbon dioxide is an odorless, tasteless, transparent gas that forms when people burn fuels, including coal, oil, gasoline and wood.

The Bank of England governor warned last week of ‘apocalyptic’ food price rises. Yet war in Ukraine, climate change and inflation are already taking their toll all over the world. Apocalypse is an alarming idea, commonly taken to denote catastrophic destruction foreshadowing the end of the world. But in the original Greek, apokálypsis means a revelation or an uncovering. One vernacular definition is “to take the lid off something”.

When people talk about ways to slow climate change, they often mention trees, and for good reason. Forests take up a large amount of the planet-warming carbon dioxide that people put into the atmosphere when they burn fossil fuels. But will trees keep up that pace as global temperatures rise? With companies increasingly investing in forests as offsets, saying it cancels out their continuing greenhouse gas emissions, that’s a multibillion-dollar question.

Des chercheurs ont récemment mis en lumière un mécanisme par lequel les changements de banquise en Arctique parviennent à influencer le climat de régions situées bien au-delà du cercle polaire. Les résultats ont été publiés dans la revue Nature Communications le 19 avril dernier.

Previous studies show that city metrics having to do with growth, productivity and overall energy consumption scale superlinearly, attributing this to the social nature of cities. Superlinear scaling results in crises called ‘singularities’, where population and energy demand tend to infinity in a finite amount of time, which must be avoided by ever more frequent ‘resets’ or innovations that postpone the system's collapse. Here, we place the emergence of cities and planetary civilizations in the context of major evolutionary transitions. With this perspective, we hypothesize that once a planetary civilization transitions into a state that can be described as one virtually connected global city, it will face an ‘asymptotic burnout’, an ultimate crisis where the singularity-interval time scale becomes smaller than the time scale of innovation. If a civilization develops the capability to understand its own trajectory, it will have a window of time to affect a fundamental change to prioritize long-term homeosta

A new study describes a period of rapid global climate change in an ice-capped world much like the present—but 304 million years ago. Within about 300,000 years, atmospheric carbon dioxide levels doubled, oceans became anoxic, and biodiversity dropped on land and at sea.

The world may be facing a devastating “hidden” collapse in insect species due to the twin threats of climate change and habitat loss.

Le changement climatique a augmenté les précipitations de 5% lors de la saison record des ouragans de l’Atlantique en 2020. Au cours des 14 tempêtes qui ont atteint le statut d’ouragan, les précipitations ont été 8 % plus importantes, selon une étude publiée dans Nature Communications.

Rapid decarbonization of energy is non-negotiable if we are to avert catastrophic global heating, says the latest UN climate report.

The Working Group III report provides an updated global assessment of climate change mitigation progress and pledges, and examines the sources of global emissions. It explains developments in emission reduction and mitigation efforts, assessing the impact of national climate pledges in relation to long-term emissions goals.

Une plateforme de glace de la taille de la ville de Rome s’est effondrée en Antarctique de l’Est le 15 mars 2022, dans une zone longtemps considérée comme relativement épargnée par le changement climatique. L’effondrement s’est produit au début d’une « vague de chaleur » exceptionnelle dans la région de l’Antarctique de l’Est, qui a vu par endroits des température dépasser de 40°C les normales de saison.

Environmentalists once saw abstraction as the biggest obstacle to climate action. How, they wondered, could one focus the public on the distant future? Today, we confront the opposite problem, with the very immediacy of the crisis generating a strange paralysis. When the Intergovernmental Panel on Climate Change warned that global heating made extreme flooding more common, its new report at the end of February spurred relatively little discussion – in part because of the water covering swathes of Queensland and New South Wales. As tinnies plucked desperate residents from the deluge, who could give due weight to the warning from Prof Brendan Mackey, one of the IPPC authors, that the science clearly projected “an increase of heavy rainfall events?”

Capitalism isn’t what it used to be. Since 2008, critics of the world’s dominant economic system have been lamenting its imperviousness to change. And for good reason. In earlier epochs, financial crises and pandemics wrought economic transformation. In our own, they seem to have yielded more of the same. Before the 2008 crash, global capitalism was characterized by organized labor’s weakness, rising inequality within nations, and a growth model that offset mediocre wage gains with asset-price appreciation. All of these have remained features of the world’s economic order.

The inventor of the Brics acronym says sanctions against Russia have exposed nations’ dependence on the western economic system

The Working Group II contribution to the IPCC Sixth Assessment Report assesses the impacts of climate change, looking at ecosystems, biodiversity, and human communities at global and regional levels. It also reviews vulnerabilities and the capacities and limits of the natural world and human societies to adapt to climate change.

Momentum to phase out unabated coal use is growing globally. This transition is critical to meeting the Paris climate goals but can potentially lead to large amounts of stranded assets, especially in regions with newer and growing coal fleets. Here we combine plant-level data with a global integrated assessment model to quantify changes in global stranded asset risks from coal-fired power plants across regions and over time. With new plant proposals, cancellations, and retirements over the past five years, global net committed emissions in 2030 from existing and planned coal plants declined by 3.3 GtCO2 (25%). While these emissions are now roughly in line with initial Nationally Determined Contributions (NDCs) to the Paris Agreement, they remain far off track from longer-term climate goals. Progress made in 2021 towards no new coal can potentially avoid a 24% (503 GW) increase in capacity and a 55% ($520 billion) increase in stranded assets under 1.5 °C. Stranded asset risks fall disproportionately on emergin

Tree diversity is fundamental for forest ecosystem stability and services. However, because of limited available data, estimates of tree diversity at large geographic domains still rely heavily on published lists of species descriptions that are geographically uneven in coverage. These limitations have precluded efforts to generate a global perspective. Here, based on a ground-sourced global database, we estimate the number of tree species at biome, continental, and global scales. We estimated a global tree richness (≈73,300) that is ≈14% higher than numbers known today, with most undiscovered species being rare, continentally endemic, and tropical or subtropical. These results highlight the vulnerability of global tree species diversity to anthropogenic changes.

Berkeley Earth, a California-based non-profit research organization, has been preparing independent analyses of global mean temperature changes since 2013. The following is our report on global mean temperature during 2021.

Climate change has important implications for the health and futures of children and young people, yet they have little power to limit its harm, making them vulnerable to climate anxiety. This is the first large-scale investigation of climate anxiety in children and young people globally and its relationship with perceived government response.

Emerging ice-sheet modeling suggests once initiated, retreat of the Antarctic Ice Sheet (AIS) can continue for centuries. Unfortunately, the short observational record cannot resolve the tipping points, rate of change, and timescale of responses. Iceberg-rafted debris data from Iceberg Alley identify eight retreat phases after the Last Glacial Maximum that each destabilized the AIS within a decade, contributing to global sea-level rise for centuries to a millennium, which subsequently re-stabilized equally rapidly.

The Working Group I contribution to the Sixth Assessment Report addresses the most up-to-date physical understanding of the climate system and climate change, bringing together the latest advances in climate science, and combining multiple lines of evidence from paleoclimate, observations, process understanding, and global and regional climate simulations.

Christophe Bonneuil, directeur de recherche au CNRS, Pierre-Louis Choquet, sociologue à Sciences po, et Benjamin Franta, chercheur en histoire à l'université américaine de Stanford, ont étudié les archives du groupe pétrolier, devenu TotalEnergies, ainsi que des revues internes et des interviews, selon cet article publié dans la revue Global Environmental Change.

Les forêts européennes sont jusqu'à dix degrés plus froides en été et jusqu'à 12 degrés plus chaudes en hiver, ressort-il d'une étude à grande échelle de la KU Leuven, de l'UAntwerp et de l'UGent. C'est la première fois que l'effet isolant des forêts est cartographié de manière aussi détaillée. L'étude a été publiée lundi dans la revue scientifique Global Change Biology.

The most important climate talk at the highest political level—since the Paris climate conference in 2015—is set to take place in Glasgow, Scotland this year, from October 31 to November 12. This is the 26th Conference of Parties (COP26) of the United Nations Framework Convention on Climate Change (UNFCCC). This is not only the largest global climate summit, but also the largest global event as the sheer existence of the world will depend on the outcome of this year's conference.

Texte de Jean-David Zeitoun, docteur en médecine, docteur en épidémiologie clinique et auteur de La grande extension : histoire de la santé humaine. En 2006, le British Medical Journal écrivait que « le changement climatique en lien avec le réchauffement global est le problème de santé publique le plus urgent dans le monde ».

The IPCC is unequivocal: we must take urgent action to curb global heating and prevent catastrophe. Will our policymakers and the Cop26 conference be up to the task?

The Gulf Stream has weakened substantially in the past decades, as new data and studies show. Weather in the United States and Europe depends strongly on this ocean current, so it’s important we understand the ongoing changes and what they will mean for our weather in the future.

Global greenhouse gas emissions must peak in the next four years, coal and gas-fired power plants must close in the next decade and lifestyle and behavioural changes will be needed to avoid climate breakdown, according to the leaked draft of a report from the world’s leading authority on climate science.

Dit jaar zien we wereldwijd enorme branden die land, bos en gemeenschappen verwoesten. Waarom komen deze catastrofale branden steeds vaker voor en wat zijn de gevolgen? Hoogleraar Fire and Global Change Victor Resco de Dios: ‘Welkom in een nieuw tijdperk van bosbranden.’

As the world battles historic droughts, landscape-altering wildfires and deadly floods, a landmark report from global scientists says the window is rapidly closing to cut our reliance on fossil fuels and avoid catastrophic changes that would transform life as we know it. The state-of-the-science report from the United Nations' Intergovernmental Panel on Climate Change says the world has rapidly warmed 1.1 degrees Celsius higher than pre-industrial levels, and is now careening toward 1.5 degrees — a critical threshold that world leaders agreed warming should remain below to avoid worsening impacts.

The Working Group I contribution to the Sixth Assessment Report addresses the most up-to-date physical understanding of the climate system and climate change, bringing together the latest advances in climate science, and combining multiple lines of evidence from paleoclimate, observations, process understanding, and global and regional climate simulations.

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Une équipe de chercheurs européens a récemment montré que pour 67 % des surfaces terrestres, la reforestation augmenterait la quantité de nuages bas et aurait ainsi un effet refroidissant sur le climat global. Ces conclusions confirment que le reboisement et la préservation des forêts se présentent comme des moyens efficaces de lutte et d’adaptation au changement climatique.

The Atlantic Meridional Overturning Circulation (AMOC), a major ocean current system transporting warm surface waters toward the northern Atlantic, has been suggested to exhibit two distinct modes of operation. A collapse from the currently attained strong to the weak mode would have severe impacts on the global climate system and further multi-stable Earth system components. Observations and recently suggested fingerprints of AMOC variability indicate a gradual weakening during the last decades, but estimates of the critical transition point remain uncertain.

The Global Alliance for a Green New Deal is inviting politicians from legislatures in all countries to work together on policies that would deliver a just transition to a green economy ahead of Cop26 UN climate talks in Glasgow this November.

Scientists know that global warming is changing clouds, but they haven’t been sure whether those changes would heat or cool the planet overall. It’s an important question, because clouds have been the main source of uncertainty in projecting just how sensitive the climate is to increasing greenhouse gas concentrations, and because clouds have a huge effect on the climate system.

Climate change and deforestation have flipped a large swathe of the Amazon basin from absorbing to emitting planet-warming carbon dioxide (CO2), a transformation that could turn humanity's greatest natural ally in the fight against global warming into a foe, researchers reported on Wednesday.

Ce concept suppose que tous les pays financent à hauteur de leurs moyens un ensemble de biens publics mondiaux. Un changement qui serait à la fois juste et vital.

A la fin du mois de juin 2021, le nord-ouest des États-Unis et l’ouest du Canada ont connu une vague de chaleur exceptionnelle. Si la tendance de fond au réchauffement climatique augmente l’intensité de ce type d’événement, les valeurs atteintes ont surpris les scientifiques. Une analyse du World Weather Attribution – un consortium d’experts climatiques du monde entier travaillant sur l’attribution d’événements extrêmes – évalue l’impact du réchauffement climatique dans la survenue de cet épisode caniculaire.

What could bring down the industrial civilization? Would it be global warming (fire) or resource depletion (ice)? At present, it may well be that depletion is hitting us faster. But, in the long run, global warming may hit us much harder. Maybe the fall of our civilization will be Fire AND ice.

On Sunday this week Zakaria ended his program with a concise description of an effective approach to address climate change – in just a few minutes he described how carbon fee-and-dividend could be made near-global. I won’t try to summarize his take – it’s impossible to match his clarity and brevity, which includes great illustrations.

More than half the world’s rivers stop flowing for at least one day per year, according to the first detailed global map of river flow. More rivers than that are expected to run dry if climate change and water management issues aren’t addressed.

Pour la première fois, GIEC et de l’IPBES publient un rapport conjoint sur les liens entre le changement climatique et la perte de biodiversité. Les crises climatiques et de la biodiversité doivent être pensées et traitées ensemble, en veillant à éviter de nuire à l’une en cherchant à protéger l’autre, soulignent des experts de l’ONU à quelques mois de deux importantes réunions internationales sur ces sujets.

The world’s coal producers are currently planning as many as 432 new mine projects with 2.28 billion tonnes of annual output capacity, research published on Thursday showed, putting targets for slowing global climate change at risk. China, Australia, India and Russia account for more than three quarters of the new projects,

Sous la houlette du laboratoire d'études en géophysique et océanographie spatiales du CNES, une équipe internationale a mesuré l'évolution de l'ensemble des glaciers mondiaux sur une période de 20 ans. En moyenne, leur masse diminue de 267 milliards de tonnes par an, soit une perte cumulée de 4% en seulement 20 ans. Les auteurs confirment que ce phénomène s'accélère au niveau global avec la hausse des températures, et explique certains ralentissements au niveau local.

Flying is a highly controversial topic in climate debates. It accounts for around 2.5% of global CO₂ emissions, but 3.5% when we take non-CO₂ impacts on climate into account.

Parties intégrantes du cycle de l'eau, les nappes d'eaux souterraines nécessitent d'être mieux prises en compte et intégrées dans les politiques de gestion de l'eau, surtout avec les conséquences du changement climatique qui se profilent.

Based on preliminary analysis, the global average atmospheric carbon dioxide in 2020 was 412.5 parts per million (ppm for short), setting a new record high amount despite the economic slowdown due to the COVID-19 pandemic. In fact, the jump of 2.6 ppm over 2019 levels was the fifth-highest annual increase in NOAA's 63-year record. Since 2000, the global atmospheric carbon dioxide amount has grown by 43.5 ppm, an increase of 12 percent.

Today, the average global temperature has increased by more than 1°C compared to pre-industrial values (Figure 1-1); atmospheric CO2 concentrations have risen from 280 to more than 400 ppm. At the current pace of emissions, the carbon budget that is left for staying below the 2°C target of the Paris Agreement will be depleted in a few tens of years. For the 1.5°C target, this budget will be exhausted before the decade is out.