8 mars

OA - Liste


A l’occasion de la « Journée internationale des femmes » (définition ONU) ou de la journée célébrant les combats pour les droits des femmes, voici une liste (non-exhaustive) de signatures féminines référencées par l’Observatoire dans le cadre des thématiques traitées dans notre veille documentaire:

espace50x10

filtre:
Global

2025

The startup Gigablue announced with fanfare this year that it reached a historic milestone: selling 200,000 carbon credits to fund what it describes as a groundbreaking technology in the fight against climate change . But outside scientists frustrated by the lack of information released by the company say serious questions remain about whether Gigablue’s technology works as the company describes. Their questions showcase tensions in an industry built on little regulation and big promises — and a tantalizing chance to profit.
Malgré le ralentissement des émissions globales de gaz à effet de serre (GES), les voyants du climat restent dans le rouge, nous rappelle le rapport Indicators of Global Climate Change 2024 récemment publié. Ce rapport permet également d’identifier trois leviers d’action à mettre en œuvre pour stabiliser le stock atmosphérique de GES à l’origine du réchauffement global.
Christophe Cassou, climatologue et auteur du GIEC dans le groupe 1, est invité sur le plateau de franceinfo suite à une étude qu'il a sorti et pour parler des vagues de chaleur actuelles. Il y explique l'évolution des températures globales et leurs conséquences. Ça fout les boules, mais qu'est-ce que ça motive.
Comment visualiser concrètement l’évolution des températures depuis 1880 ? Comment rendre accessibles les données scientifiques de la NASA ? C’est ce qui m’a motivé à créer NASA GISTEMP Viewer, une application web qui permet de voir les données sur une sphère en 3D.
Between 80% and 89% of the world’s people want their governments to do more about climate change. This fact is the central tenet of the 89% Project for climate journalism. Timed to coincide with Earth Day and Earth Week, the project launched in April, 2025, and will culminate in another week of focused stories in October, just before the next COP meeting in Brazil.
the rapid rises in global military spending threaten climate action, undermining our collective security. In a new joint paper we explore how everything from direct emissions to diverted climate finance are threatening SDG 13 on Climate action.
Militaries are huge energy users whose greenhouse gas emissions (GHG) make a significant contribution to the climate crisis. However, countries do not systematically record and report their military emissions so the real share of this source of emissions remains unclear. The Conflict and Environment Observatory (CEOBS) and Scientists for Global Responsibility estimate that everyday military activity could be responsible for around 5.5% of global emissions, meaning that if the world’s militaries were a country, they would be the fourth largest emitter in the world.6 Furthermore, as military spending increases and the rest of society decarbonises, that proportion is set to rise.
The climate crisis has entered a decisive phase. Delaying climate measures increases the likelihood of crossing tipping points. Political shifts are weakening international cooperation when unity is vital. Yet, the Planetary Boundaries offer a path to a stable and sustainable future.
Iran’s parliament approved a measure to close the vital global trade route, through which more than a fifth of the world’s oil supply passes through daily
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
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.
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.
The human fingerprint on global warming was likely evident in Earth’s atmosphere far earlier than previously thought—even before the invention of modern cars, a new study says. Using a combination of scientific theory, modern observations and multiple, sophisticated computer models, researchers found a clear signal of human-caused climate change was likely discernible with high confidence as early as 1885, just before the advent of gas-powered cars but after the dawn of the industrial revolution.
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.
L’accord sur les pandémies signé en mai 2025 par les États membres de l’Organisation mondiale de la santé (OMS) est présenté comme un succès historique du multilatéralisme. Pourtant, il pourrait se révéler délétère pour les autres priorités de santé globale, du fait de la gouvernance technocratique qu’il propose et des coûts financiers élevés qui seraient alloués à des risques pandémiques hypothétiques.
Face à l’emballement simultané des crises écologiques, économiques, sociales, politiques et existentielles, nos sociétés semblent piégées dans une fuite en avant. Loin de simples dysfonctionnements, c’est un effondrement structurel qui se profile : celui des équilibres vitaux de notre biosphère, mais aussi de nos représentations collectives, de nos institutions démocratiques et de notre capacité à percevoir le réel. Dans cet article, Jacques de Gerlache explore les racines systémiques de cette crise de civilisation, et pointe notamment l’une de ses carences majeures : l’absence, au sein des mouvements socio-politiques constructifs du XXe siècle, d’une métaphysique émotionnelle et spirituelle capable de nourrir des récits mobilisateurs, porteurs d’espoir, d’incarnation et de plaisir partagé à construire ensemble.
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
Understanding how global mean surface temperature (GMST) has varied over the past half-billion years, a time in which evolutionary patterns of flora and fauna have had such an important influence on the evolution of climate, is essential for understanding the processes driving climate over that interval. Judd et al. present a record of GMST over the past 485 million years that they constructed by combining proxy data with climate modeling (see the Perspective by Mills). They found that GMST varied over a range from 11° to 36°C, with an “apparent” climate sensitivity of ∼8°C, about two to three times what it is today. —Jesse Smith
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
L’Organisation Météorologique Mondiale (OMM) publie ses prévisions climatiques pour les cinq prochaines années, 2025-2029. Selon l’OMM, les températures de la terre oscilleront entre +1.2°C et + 1.9°C, ce qui nous amène très près de 2°C de réchauffement en 2030 (OMM). Nous serons alors proches du climat annoncé pour la France à 4°C.
Critical minerals, which are essential for a range of energy technologies and for the broader economy, have become a major focus in global policy and trade discussions. Price volatility, supply chain bottlenecks and geopolitical concerns make the regular monitoring of their supply and demand extremely vital.
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.
Nouveau "TALK" sur LIMIT avec Matthieu Auzanneau,, auteur et directeur du think tank de la transition énergétique The Shift Project nous abordons l’inexorable épuisement des ressources fossiles et ses conséquences géopolitiques (Golfe Persique, Irak, Ukraine) La dépendance de l’Europe au pétrole et au gaz. Les grands moments historiques du pétrole (pic de 1970, Mer du Nord, boom du shale aux USA) Les premiers accords climatiques (Protocole de Kyoto) et la croissance paradoxale de la consommation de gaz L’analogie du corps humain pour montrer que l’énergie est l’« organe vital » de nos sociétés Les pistes de sortie de la « marriage pétrolier » : sobriété organisée, souveraineté industrielle, transition vers les renouvelables Et un appel à l’élaboration d’un plan clair et collectif pour réduire la dépendance aux énergies carbonées « Decarbonons la France ! »
When it comes to our understanding of the unfolding global crisis, each of us seems to fit somewhere along a continuum of awareness that can be roughly divided into five stages:
Acute global food insecurity rose for the sixth year in a row in 2024, according to the 2025 Global Report on Food Crises (GRFC), a collaborative effort coordinated by the Food Security Information Network. The report shows that climate extremes, conflict, forced displacement and economic shocks continue to drive malnutrition and food insecurity around the world, with disastrous impacts on those living in many of the most vulnerable regions in the world.
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.
Small particulate matter (PM2.5) in air pollution raises the risks of respiratory problems, cardiovascular disease, and even cognitive decline. Heat waves, which are occurring more often with climate change, can cause heatstroke and exacerbate conditions such as asthma and diabetes. When heat and pollution coincide, they can create a deadly combination.
For around 2,000 years, global sea levels varied little. That changed in the 20th century. They started rising and have not stopped since — and the pace is accelerating. Scientists are scrambling to understand what this means for the future just as President Trump strips back agencies tasked with monitoring the oceans.
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
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.
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.
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.
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.
2023 set a number of alarming new records. The global mean temperature also rose to nearly 1.5 degrees Celsius above the preindustrial level, another record.A team led by the Alfred Wegener Institute puts forward a possible explanation for the rise in global mean temperature: our planet has become less reflective because certain types of clouds have declined. The work is published in the journal Science.
We develop roadmaps to transform the all-purpose energy infrastructures (electricity, transportation, heating/cooling, industry, agriculture/forestry/fishing) of 139 countries to ones powered by wind, water, and sunlight (WWS). The roadmaps envision 80% conversion by 2030 and 100% by 2050. WWS not only replaces business-as-usual (BAU) power, but also reduces it ∼42.5% because the work: energy ratio of WWS electricity exceeds that of combustion (23.0%), WWS requires no mining, transporting, or processing of fuels (12.6%), and WWS end-use efficiency is assumed to exceed that of BAU (6.9%). Converting may create ∼24.3 million more permanent, full-time jobs than jobs lost. It may avoid ∼4.6 million/year premature air-pollution deaths today and ∼3.5 million/year in 2050; ∼$22.8 trillion/year (12.7 ¢/kWh-BAU-all-energy) in 2050 air-pollution costs; and ∼$28.5 trillion/year (15.8 ¢/kWh-BAU-all-energy) in 2050 climate costs. Transitioning should also stabilize energy prices because fuel costs are zero, reduce power d
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.
Metals and metalloids are ubiquitous in soils, originating from bedrock and from human activities and infrastructure. These compounds can be toxic to humans and other organisms, and their soil distribution and concentrations at global scale are not well known. Hou et al. analyzed data from more than 1000 regional studies to identify areas of metal toxicity and explore drivers of these trends. They estimate that 14 to 17% of cropland exceeds agricultural thresholds for at least one toxic metal.
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.
La Suisse et le Nord de l’Italie ont subi des précipitations exceptionnelles, qui ne se produisaient avant qu’une fois par siècle. Un courant du sud très humide est monté vers les Alpes où un front froid est arrivé mercredi (MétéoSuisse 14 avril). Une pluie torrentielle a suivi ce choc de masses d’air.
Global temperature for 2025 should decline little, if at all, from the record 2024 level. Absence of a large temperature decline after the huge El Nino-spurred temperature increase in 2023-24 will provide further confirmation that IPCC’s best estimates for climate sensitivity and aerosol climate forcing were both underestimates. Specifically, 2025 global temperature should remain near or above +1.5C relative to 1880-1920, and, if the tropics remain ENSO-neutral, there is good chance that 2025 may even exceed the 2024 record high global temperature.
Dans cet épisode, Arnaud reçoit Laurent Testot, journaliste, historien et vulgarisateur scientifique reconnu pour ses travaux sur l’histoire globale et les grands changements environnementaux. Auteur de plusieurs ouvrages, dont « Cataclysme » et « Omokanis », il nous livre une réflexion fascinante sur l’impact humain sur la Terre. Avec Laurent, nous explorons l'impact de l'humanité sur la Terre, de la domestication des chiens aux mutations écologiques du Sahara, en décryptant les grands défis de l'Anthropocène : l'accélération de la crise climatique, la sixième extinction de masse et l'influence des politiques mondiales. C'est une réflexion urgente pour repenser notre rapport à la nature, à l'agriculture et aux écosystèmes.
Tipping elements within the Earth system are increasingly well understood. Scientists have identified more than 25 parts of the Earth’s climate system that are likely to have “tipping points” – thresholds where a small additional change in global warming will cause them to irreversibly shift into a new state. The “tipping” of these systems – which include the Atlantic Meridional Overturning Circulation (AMOC), the Amazon rainforest and the Greenland ice sheet – would have profound consequences for both the biosphere and people. More recent research suggests that triggering one tipping element could cause subsequent changes in other tipping elements, potentially leading to a “tipping cascade”. For example, a collapsed AMOC could lead to dieback of the Amazon rainforest and hasten the melt of the Greenland ice sheet.
Eat-Lancet report recommended shift to more plant-based, climate-friendly diet but was extensively attacked online [...] The report recommended that if global red meat eating was cut by 50%, the “planetary health diet” would provide nutritious food to all while tackling the harms caused by animal agriculture, which accounts for over 14% of all greenhouse gas emissions worldwide. It suggested individuals – particularly in wealthy countries – should increase their consumption of nuts, pulses and other plant-based foods while cutting meat and sugar from their diets.
Les températures de la Planète augmenteront pendant les prochaines décennies. Les catastrophes climatiques s’aggraveront au cours de cette période. A 2°C, il y aura beaucoup plus d’inondations et des vagues de chaleur plus fortes. Nous les subirons de plein fouet, probablement au cours des vingt prochaines années (James E.Hansen).
January 2025 was the 18th month in a 19-month period with a global-average surface air temperature exceeding 1.5ºC above pre-industrial levels. According to the Copernicus Climate Change Service…
Des employés d’une décharge gérée par la multinationale française ont été filmés en train de déverser des résidus liquides directement dans un cours d’eau. Cette pratique met en péril la santé des écosystèmes et des habitants de la région.
L’Organisation Météorologique Mondiale a publié son rapport annuel (OMM2024). L’année 2024 a été la plus chaude de l’Histoire. Elle a apporté de nombreux événements extrêmes. Le cyclone Yagi a causé des dégâts étendus en Chine, au Philippines et au Vietnam, et le cyclone Chido a dévasté Mayotte et le Mozambique. De nombreux affluents de l’Amazone se sont taris par une chaleur inhabituelle, et plus de mille pèlerins ont succombé à la chaleur à la Mecque.
The clear signs of human-induced climate change reached new heights in 2024, which was likely the first calendar year to be more than 1.5°C above the pre-industrial era, with a global mean near-surface temperature of 1.55 ± 0.13 °C above the 1850-1900 average.
Our study presents a global assessment of microplastic pollution’s impact on food security. By analyzing a comprehensive dataset of 3,286 records, we quantify the reduction in photosynthesis caused by microplastics across various ecosystems.
Countries must move rapidly to slash CO2 emissions from homes, offices, shops and other buildings—a sector that accounts for a third of global greenhouse gas pollution, the United Nations said Monday. Carbon dioxide emissions from the building sector rose around 5% in the last decade when they should have fallen 28%, according to a new report by the United Nations Environment Program (UNEP).
The world is warming despite natural fluctuations from the El Niño cycle.
Global temperature leaped more than 0.4°C (0.7°F) during the past two years, the 12-month average peaking in August 2024 at +1.6°C relative to the temperature at the beginning of last century (the 1880-1920 average). This temperature jump was spurred by one of the periodic tropical El Niño warming events, but many Earth scientists were baffled by the magnitude of the global warming, which was twice as large as expected for the weak 2023-2024 El Niño.
Theo Francken a préparé un plan de résilience si la Belgique est attaquée sur son propre sol par la Russie.
... An “acid” test of our interpretation will be provided by the 2025 global temperature: unlike the 1997-98 and 2015-16 El Ninos, which were followed by global cooling of more than 0.3°C and 0.2°C, respectively, we expect global temperature in 2025 to remain near or above the 1.5°C level. Indeed, the 2025 might even set a new record despite the present weak La Nina. There are two independent reasons. First, the “new” climate forcing due to reduction of sulfate aerosols over the ocean remains in place, and, second, high climate sensitivity (~4.5°C for doubled CO2) implies that the warming from recently added forcings is still growing significantly.
Où en est l’effort environnemental des États européens ? Les 27 États membres de l’UE se sont fixés des engagements pour réagir au changement climatique et à ses conséquences, aux problèmes de qualité de l’air qui provoquent des décès précoces, à la chute de la biodiversité.
Les événements centennaux, vagues de chaleurs qui frappaient tous les cent ans par le passé, se produisent maintenant tous les dix ou vingt ans. Dans le futur, des épisodes plus graves, aux températures plus élevées, se produiront, et atteindront des températures fatales pour les populations. Les canicules comportent d’autres dangers qui incluent la sécheresse, la mort du bétail et les incendies.
Un nouvel article du grand climatologue James Hansen affirme que le réchauffement a accéléré il y a quelques années. La réduction des aérosols liés au fuel des navires en serait la cause. La fonte du Groenland dépasse les prévisions et mènera à un arrêt de la circulation océanique dans 20 -30 ans, ce qui provoquera plus tard une importante montée du niveau de la mer. Il suggère des prévisions climatiques complémentaires à celles du GIEC, qui s’appuieraient plus sur les observations de la réalité.
The climate science maverick believes catastrophe is inevitable, carbon offsetting is a joke and ethical living a scam. So what would he do?
Human-driven ocean warming is increasingly overwhelming El Niño, La Niña, and other natural climate patterns.
2024 was the warmest year on Earth since direct observations began, and recent warming appears to be moving faster than expected.
An engaging discussion on groundbreaking research that reveals the unexpected drivers behind the recent unprecedented rise in global temperatures. Moderated by SDSN President Professor Jeffrey Sachs, this virtual event explored Dr. James Hansen and colleagues' findings in the latest publication, “Global Warming Has Accelerated,” their implications for climate sensitivity, and the urgent need for alternative approaches to mitigate the looming "point of no return."
An international group of scientists, led by King's College London, has revealed how continued global warming will lead to more parts of the planet becoming too hot for the human body over the coming decades. the amount of landmass on our planet that would be too hot for even healthy young humans (18 to 60-year-olds) to keep a safe core body temperature will approximately triple (to 6%)—an area almost the size of the US—if global warming reaches 2°C above the preindustrial average.
« Drill, baby drill » par contre, brille surtout par son absurdité. Le climat change très vite et les énergies renouvelables s’imposent trop lentement au niveau mondial. Pendant ce temps, le gaz carbonique s’accumule dans l’atmosphère, et les températures montent. Les déclarations incohérentes de Trump à ce sujet seront bientôt balayées par quelques tempêtes. Le problème du climat deviendra alors évident pour tous. En 2023, James Hansen calculait que la vitesse de changement actuelle nous menait à 2°C de température mondiale vers 2040 (voir figure ci-dessous).
Some scientists fear the risk of a collapse to warm Atlantic currents has not been taken seriously.
A panel of international scientists has moved their symbolic “Doomsday Clock” closer to midnight than ever before, citing Russian nuclear threats amid its invasion of Ukraine, tensions in other world hotspots, military applications of artificial intelligence and the climate crisis as factors underlying the risks of global catastrophe.
The 20th edition of the Global Risks Report 2025 reveals an increasingly fractured global landscape, where escalating geopolitical, environmental, societal and technological challenges threaten stability and progress. This edition presents the findings of the Global Risks Perception Survey 2024-2025 (GRPS), which captures insights from over 900 experts worldwide. The report analyses global risks through three timeframes to support decision- makers in balancing current crises and longer-term priorities.
Génétique de fin. La diversité génétique des espèces animales et végétales baisse à l’échelle mondiale, révèle une vaste étude internationale publiée dans la revue Nature mercredi. Mais, à l’aide de stratégies de conservation adaptées, cette tendance pourrait s’inverser.
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%.
he global economy could face 50% loss in gross domestic product (GDP) between 2070 and 2090 from the catastrophic shocks of climate change unless immediate action by political leaders is taken to decarbonise and restore nature, according to a new report The stark warning from risk management experts the Institute and Faculty of Actuaries (IFoA) hugely increases the estimate of risk to global economic wellbeing from climate change impacts such as fires, flooding, droughts, temperature rises and nature breakdown.
The world could fall short of food by 2050 due to falling crop yields, insufficient investment in agricultural research and trade shocks, according to Joe Biden’s special envoy for food security, Dr Cary Fowler. Fowler, who is also known as the “father” of the Svalbard Global Seed Vault, a global store of seeds for the most significant crops, said studies by agricultural economists showed the world needed to produce 50-60% more food by 2050 in order to feed its growing population. But crop yields rates were projected to decline by between 3-12% as a result of global heating.
NASA satellites discovered that Earth's surface has lost enough water to empty Lake Erie two and a half times since 2015. And the problem could be here to stay.
As authorities declared 2024 the hottest on record, a key private sector climate alliance, the Glasgow Financial Alliance for Net Zero (GFANZ) abandoned a requirement that members be aligned to the Paris agreement. That was followed by a network of net zero asset managers suspending work, and deleting from its website its statement of commitments that members must adopt, after BlackRock, the biggest of them all, quit its ranks.
Un climatologue nous a contactés pour partager avec le public les changements climatiques qui se produisent en France. Il a constaté un réchauffement très rapide, particulièrement sur une période sensible pour la végétation. Vincent Cailliez, lauréat du prix André Prud’homme, décerné par la Société Météorologique de France (Météo et Climat), partage avec nous les conclusions de son travail.
Wildfires that blazed around the world in 2024 helped to drive a record annual leap in carbon dioxide levels in the atmosphere, surprising scientists. The data shows humanity is moving yet deeper into a dangerous world of supercharged extreme weather.
Les événements météorologiques extrêmes sont plus fréquents et plus forts. Les vagues de chaleur qui se produisaient tous les cinquante ans frappent déjà tous les dix ans. Elles pourraient devenir quasiment permanentes dans de grandes parties du monde, et des records bien plus intenses se produiront alors.

2024

The new study, led by researchers at the Global Systems Institute, University of Exeter, associated with the Earth Commission, and Nanjing University, assessed what this would mean for the number of people living outside the “climate niche” in which our species has thrived. It says about 60 million people are already exposed to dangerous heat (average temperature of 29°C or higher). And two billion – 22% of the projected end-of-century population – would be exposed to this at 2.7°C of global warming.
L’année passée, la température terrestre a grimpé d’environ un demi-degré. Il s’avère aujourd’hui que la planète dans l’ensemble a vécu une année ensoleillée. Les nuages bas étaient 4% moins abondants que les années précédentes. L’année 2023 a vu une augmentation impressionnante du réchauffement climatique. Les océans étaient particulièrement chauds, notamment l’Atlantique, qui a battu tous les records. Les climatologues ont qualifié ce changement de plusieurs adjectifs expressifs, incluant ‘gobsmackingly bananas.’
Les récentes conférences de l’ONU sur le climat (COP29) et sur la biodiversité (COP16) ont encore une fois contribué à perpétuer un système fondé sur des illusions d’égalité, de liberté et de croissance infinie. La société civile et les pays du Sud global présents à ces négociations s’y activent de manière exemplaire, mais pour combien de temps encore ?
Klimaatrampen, vergrijzing, de digitale kloof: het zijn enorme uitdagingen die de toekomst van volgende generaties op het spel zetten, stelt Unicef in een nieuw rapport. De VN-organisatie pleit voor dringende actie om de rechten van kinderen te waarborgen in een snel veranderende wereld.
Le sommet des plus grandes économies de la planète s’est ouvert lundi sous la houlette du président brésilien de gauche. Celui-ci a notamment réussi à mettre sur orbite son Alliance globale contre la faim et la pauvreté et a convaincu ses homologues d’endosser l’idée d’une coopération pour taxer les plus fortunés.
Au sommet du G20 à Rio de Janeiro, les négociations climat ont fait du surplace lundi après la COP29 de la semaine passée. Le président brésilien, à la tête du forum, a cependant réussi à lancer une Alliance globale contre la faim et a obtenu un engagement commun à coopérer pour une taxation effective des plus fortunés.
Un rapport remis en mai au précédent gouvernement, mais jamais publié, préconise plusieurs mesures d’urgence pour protéger les captages d’eau. Aucune n’a encore été mise en œuvre.
De nombreuses voix africaines – exclues de la Conférence des Parties à la Convention-cadre des Nations Unies sur les changements climatiques – ont été captées et légitimées lors de ce rassemblement. C’était « un moment pour dénoncer le système des COP, souligner les impacts du changement climatique sur les communautés africaines et présenter des solutions alternatives viables », comme le souligne leur déclaration (à lire ci-dessous).
Hystérie, escroquerie, catastrophisme… Les mots ne manquent pas pour accabler ceux qui tentent d’alerter l’Humanité sur la possibilité d’un effondrement lié au climat. Pourtant, le réchauffement global pourrait nous faire entrer dans des zones d’incertitudes très importantes.
Les émissions de CO2 issues des énergies fossiles ont augmenté de 0,8 % par rapport à 2023, estiment les scientifiques du Global Carbon Project dans un rapport. Ce qui augure d'un réchauffement de 2 °C atteint dans 27 ans.
Les plans mondiaux de réduction des émissions de carbone impliquent que la température dépassera 1.5°C, puis redescendra après vingt ou trente ans. Cependant, une nouvelle étude montre que des décennies au-dessus de ce seuil entraîneraient des « conséquences irréversibles » pour la planète.
Le philosophe, romancier et essayiste participera à la table ronde « Agriculture et alimentation : comment accélérer les transitions ? » dans le cadre du festival Néo Terra qui se tiendra à Darwin, à Bordeaux, du 28 au 30 novembre, en partenariat avec « Le Monde ».
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.
These powerful ‘rivers in the sky’ provide a huge share of annual precipitation in many regions, including California. They can also melt sea ice, with global climate implications.
Surpassing 1.5°C of warming can be undone at a later date – using tech, land and resources that don’t exist.
.  Trois ouragans inhabituels ont touché la Terre autour du 25 octobre. Le cyclone Otis a dévasté la côte pacifique du Mexique, en particulier Acapulco. Dans l’hémisphère Sud, Lola s&rsq…
Allen samen op vrijdag 20 september om 17.30 uur in Brussel-Centraal!CONCERT EN MARS #NowForFutureTer gelegenheid van de Global Climate Strike roepen Youth for Climate, Rise for Climate, Grootouders voor het Klimaat en anderen op tot mobilisatie om politieke leiders te herinneren aan het belang van sociaal- en klimaatrechtvaardige maatregelen.We willen een beroep doen op de staatshoofden van de wereld die op 22 en 23 september bij de VN bijeenkomen voor een wereldtop over de toekomst.
Global average surface temperatures shattered all-time records in 2023 at 1.45 ± 0.12 ◦C above pre- industrial levels (WMO 2024). Worsened by climate change-induced drought, Canadian wildfires burned 18.5 million hectares, nearly three-times more land area than in any previous year on record (NRC 2023).
Steden in het Globale Zuiden zijn bijzonder kwetsbaar voor extreme hitte omdat ze gemiddeld minder groen hebben, stelt internationaal onderzoek in het vakblad Nature. Parken, bossen en ander groen kunnen de temperatuur in de stad met 3 graden verlagen.
High-level policy discussions have built momentum for “food system transformation” that would help farmers address the climate crisis.
Un des plus importants climatologues européens, Johan Rockström, a confirmé que le réchauffement s’accélère et que ses effets sont plus graves que prévu. Nous pourrions atteindre les 2°C dans 20 ans.
Ter gelegenheid van de Global Climate Strike roepen Youth for Climate, Rise for Climate, Grootouders voor het Klimaat politieke leiders op om sociaal-rechtvaardige klimaatmaatregelen te nemen. De wereldwijde klimaatstakingen, in 2019 gelanceerd door Fridays For Future op initiatief van Greta Thunberg, brengen jongeren, burgers en organisaties van over de hele wereld samen om zich te verzetten tegen de vernietiging van het klimaat en ecosystemen.
Plafonner les émissions, avec un prix mondial du carbone finançant un revenu de base mondial
An extensive new multi-proxy database of paleo-temperature time series (Temperature 12k) enables a more robust analysis of global mean surface temperature (GMST) and associated uncertainties than was previously available. We applied five different statistical methods to reconstruct the GMST of the past 12,000 years (Holocene). Each method used different approaches to averaging the globally distributed time series and to characterizing various sources of uncertainty, including proxy temperature, chronology and methodological choices. The results were aggregated to generate a multi-method ensemble of plausible GMST and latitudinal-zone temperature reconstructions with a realistic range of uncertainties. The warmest 200-year-long interval took place around 6500 years ago when GMST was 0.7 °C (0.3, 1.8) warmer than the 19th Century (median, 5th, 95th percentiles). Following the Holocene global thermal maximum, GMST cooled at an average rate −0.08 °C per 1000 years (−0.24, −0.05). The multi-method ensembles and th
UN says a global ‘backlash’ against climate action is being stoked by fossil fuel companies
Cette semaine j’ai eu peur. Le Monde a publié la nouvelle que les puits de carbone terrestres se sont effondrés en 2023. Au cours des mois passés, des calculs précis ont été effectués sur les mesures satellitaires de l’année passée. Il s’avère que les forêts et les sols ont absorbé environ deux (1,5 – 2.6) milliards de tonnes de CO2, alors que l’année précédente ils avaient capté plus de 9 milliards. La sécheresse en Amazonie, et les feux au Canada et en Sibérie ont provoqué une émission de carbone de ces écosystèmes (FranceInfo).
En 2023 les températures de la Planète, et notamment de l’Atlantique Nord, ont fait un bond. Le réchauffement a accéléré. Les scientifiques étaient très inquiets, puis ont trouvé une explication.
Les épisodes de contamination de la Seine aux bactéries fécales montrent les limites du tout-à-l’égout, loin d’être une panacée sanitaire. Des solutions pour mieux confiner les pathogènes existent.
Notre système alimentaire utilise près de la moitié des terres de la Planète. Il provoque des émissions de carbone et aggrave le réchauffement climatique. Il entraîne donc la perte de biodiversité par la réduction de l’espace laissé aux écosystèmes et par le changement climatique. Une nouvelle étude a tenté de quantifier ces effets. Les dommages à la biodiversité ont été estimés en prenant en compte la richesse des écosystèmes et la rareté de espèces, par exemple leur présence dans une zone restreinte. Les dommages aux écosystèmes riches et uniques, notamment en Amérique centrale et du Sud apparaissent donc mieux dans cette analyse.
Sudden cut in pollution in 2020 meant less shade from sun and was ‘substantial’ factor in record surface temperatures in 2023, study finds
Monthly global surface air temperature anomalies (°C) relative to 1850–1900 from January 1940 to June 2024, plotted as time series for all 12-month periods spanning July to June of the following year. The 12 months from July 2023 to June 2024 are shown with a thick red line, while all other 12-month periods are shown with thin lines shaded according to the decade, from blue (1940s) to brick red (2020s).
New research shows the company’s scientists were as “skillful” as independent experts in predicting how the burning of fossil fuels would warm the planet and bring about climate change.
Carbon Brief provides an updated analysis of when the world will likely exceed the Paris 1.5C limit
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
Le secrétaire-général de l’ONU appelle à une action immédiate pour le climat. Selon lui, la décennie actuelle est décisive. Le GIEC a publié leurs calculs détaillés concernant l’année 2023. Cette s…
Natural ecosystems store large amounts of carbon globally, as organisms absorb carbon from the atmosphere to build large, long-lasting, or slow-decaying structures such as tree bark or root systems. An ecosystem’s carbon sequestration potential is tightly linked to its biological diversity. Yet when considering future projections, many carbon sequestration models fail to account for the role biodiversity plays in carbon storage. Here, we assess the consequences of plant biodiversity loss for carbon storage under multiple climate and land-use change scenarios. We link a macroecological model projecting changes in vascular plant richness under different scenarios with empirical data on relationships between biodiversity and biomass. We find that biodiversity declines from climate and land use change could lead to a global loss of between 7.44-103.14 PgC (global sustainability scenario) and 10.87-145.95 PgC (fossil-fueled development scenario). This indicates a self-reinforcing feedback loop, where higher levels
Annually updated, IPCC AR6 consistent indicators of human-induced global warming, greenhouse gas emissions, and the remaining global carbon budget.
As the public conversation on climate change evolves, so too does the sophistication and range of arguments used to downplay or discount the need for action (McKie, Reference McKie2019; Norgaard, Reference Norgaard2011). A mainstay of this counter-movement has been outright denial of the reality or human causation of climate change (Farrell et al., Reference Farrell, McConnell and Brulle2019), supplemented by climate-impact scepticism (Harvey et al., Reference Harvey, Van Den Berg, Ellers, Kampen, Crowther, Roessingh and Mann2018) and ad hominem attacks on scientists and the scientific consensus (Oreskes & Conway, Reference Oreskes and Conway2011). A fourth strategy has received relatively little attention to date: policy-focused discourses that exploit contemporary discussions on what action should be taken, how fast, who bears responsibility and where costs and benefits should be allocated (Bohr, Reference Bohr2016; Jacques & Knox, Reference Jacques and Knox2016; McKie, Reference McKie2019). We call these ‘
Global temperature (12-month mean) is still rising at 1.56°C relative to 1880-1920 in the GISS analysis through April (Fig. 1). [Robert Rohde reports that it is 1.65°C relative to 1850-1900 in the BerkeleyEarth analysis.[3]] Global temperature is likely to continue to rise a bit for at least a month, peak this summer, and then decline as the El Nino fades toward La Nina. Acceleration of global warming is now hard to deny. The GISS 12-month temperature is now 0.36°C above the 0.18°C/decade trend line, which is 3.6 times the standard deviation (0.1°C). Confidence in global warming acceleration thus exceeds 99%, but we need to see how far temperature falls with the next La Nina before evaluating the post-2010 global warming rate.
L’effondrement des écosystèmes serait dangereux pour l’économie. Il peut se répercuter au niveau global. La forêt amazonienne, les tourbières tropicales et les mangroves contiennent actuellement environ 220 gigatonnes de carbone. Si elles sont perturbées, elles peuvent subir des changements incontrôlables qui feraient basculer l’écosystème vers une savane non boisée. Leur effondrement provoquerait des émissions de carbone équivalentes à environ 20 ans d’émissions mondiales de CO2 actuelles. Cela pourrait empêcher le maintien d’un climatique de moins d’ 1,5°C, et aurait de nombreuses conséquences directes.
Global Report on Food Crises (GRFC) 2024
Exclusive: Planet is headed for at least 2.5C of heating with disastrous results for humanity, poll of hundreds of scientists finds
The Global Tipping Points Report was launched at COP28 on 6 December 2023. The report is an authoritative assessment of the risks and opportunities of both negative and positive tipping points in the Earth system and society. Global Tipping Points is led by Professor Tim Lenton from the University of Exeter’s Global Systems Institute with the support of more than 200 researchers from over 90 organisations in 26 countries.
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
L’analyse de 186 études d’évaluation de différentes mesures de conservation de part le monde prouve l’efficacité globale de ces dispositifs. Mais il faut en faire plus pour éradiquer la chute du vivant en cours.