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There is increasing concern that the Atlantic Meridional Overturning Circulation (AMOC) may collapse this century with a disrupting societal impact on large parts of the world. Preliminary estimates of the probability of such an AMOC collapse have so far been based on conceptual models and statistical analyses of proxy data. Here, we provide observationally based estimates of such probabilities from reanalysis data. We first identify optimal observation regions of an AMOC collapse from a recent global climate model simulation. Salinity data near the southern boundary of the Atlantic turn out to be optimal to provide estimates of the time of the AMOC collapse in this model. Based on the reanalysis products, we next determine probability density functions of the AMOC collapse time. The collapse time is estimated between 2037-2064 (10-90% CI) with a mean of 2050 and the probability of an AMOC collapse before the year 2050 is estimated to be 59±17%.

Under current emission trajectories, temporarily overshooting the Paris global warming limit of 1.5 °C is a distinct possibility. Permanently exceeding this limit would substantially increase the probability of triggering climate tipping elements. Here, we investigate the tipping risks associated with several policy-relevant future emission scenarios, using a stylised Earth system model of four interconnected climate tipping elements. We show that following current policies this century would commit to a 45% tipping risk by 2300 (median, 10–90% range: 23–71%), even if temperatures are brought back to below 1.5 °C. We find that tipping risk by 2300 increases with every additional 0.1 °C of overshoot above 1.5 °C and strongly accelerates for peak warming above 2.0 °C. Achieving and maintaining at least net zero greenhouse gas emissions by 2100 is paramount to minimise tipping risk in the long term. Our results underscore that stringent emission reductions in the current decade are critical for planetary stabili

La France s’est fixé l’objectif ambitieux d’atteindre la neutralité carbone en 2050. La forêt et le bois sont des éléments clés dans cette stratégie du fait de leur capacité à séquestrer du carbone et à éviter, grâce à l’emploi du bois, des émissions de carbone fossile.

Le Shift Project présente son rapport intermédiaire "Pour une agriculture bas carbone, résiliente et prospère"

Ce document présente l'Opération REGIME (Réduire Grandement et Irrémédiablement la Masse des vEhicules) menée par l’association The Shifters Belgium, qui vise à proposer des mesures concrètes pour réduire la masse moyenne des véhicules en Région de Bruxelles-Capitale (RBC). Deux outils sont envisagés : un outil réglementaire d’une part avec le développement d’une Low Danger Zone (LDZ), et un outil fiscal de l’autre avec l’adaptation du projet de réformes fiscales SmartMove. Ce document fait suite à l’analyse prospective des émissions liées aux voitures particulières à horizon 2030 réalisée par The Shifters Belgium : l’association a calculé le bilan carbone induit par les hypothèses de la réalisation du Plan Régional de Mobilité en RBC (Good Move) en 2030, et l’a comparé aux objectifs de réduction des émissions pour le secteur de la mobilité. En supplément, une série de scénarios activant différents leviers a été analysée, l’un d’eux étant la réduction de la masse des véhicules.

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

Alors que la COP 28 vient de conclure ses travaux et que le GIEC entame un nouveau cycle, les émissions de gaz à effet de serre demeurent au centre des débats sur les changements climatiques. Diverses zones riches en carbone organique, telles que le pergélisol ou les tourbières, sont affectées par les changements climatiques et contribuent à des émissions qui s'ajoutent à celles des combustibles fossiles. Afin de mieux appréhender les enjeux mondiaux liés à ces phénomènes, nous avons interviewé la Pre Sophie Opfergelt, géologue et maître de recherches FNRS à l'UCLouvain (Institut ELI), à propos de ses travaux sur le pergélisol en Alaska. Nous avons ensuite abordé le thème des tourbières tropicales avec le Pr Suspense Averti Ifo, enseignant-chercheur à ’Université Marien N'Gouab (Brazzaville, République du Congo). En fin de Lettre, l’agenda reprend des événements liés aux changements climatiques et aux activités du GIEC.

Fear appeals are a polarizing issue, with proponents confident in their efficacy and opponents confident that they backfire. We present the results of a comprehensive meta-analysis investigating fear appeals' effectiveness for influencing attitudes, intentions, and behaviors. We tested predictions f …

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

Une nouvelle mise à jour de l'inventaire composée d'une sélection de ressources pédagogiques très variées est à votre disposition. L'objectif est d'outiller les acteurs pour la mise en place sur leur territoire de projets de sensibilisation, l'organisation d'ateliers pédagogiques ou d'évènements dans le cadre d'un plan climat, d'un contrat de transition écologique ou de tout autre dispositif.

Le 4ième cycle de l'Assemblée Citoyenne Bruxelloise a terminé ses propositions pour l'énergie et le climat à Bruxelles! Découvrez ici la Résolution Citoyenne Energie-Climat.

Taking into account all known factors, the planet warmed 0.2 °C more last year than climate scientists expected. More and better data are urgently needed. Taking into account all known factors, the planet warmed 0.2 °C more last year than climate scientists expected. More and better data are urgently needed.

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

L'Ademe publie le résultat d'une enquête sur nos habitudes de consommation, et tout ce qui fait notre quotidien y passe : déplacements, logement, achats, alimentation, etc, avec 256 pages de résultats détaillés

How the EU is boosting the mining and defence industries in the name of climate action

All local communities affected by mining projects should have the right to have a say on whether mining activities will start or continue in their backyard. This belief in community involvement in political, economic, and environmental decision-making is epitomised in a Right to Say No (RTSN), which is the inalienable and collective right of a community to say no (or yes) to extractive projects on the territories/lands they are living within. Currently, there is no real ‘Right’ to Say No outside of iterations of the indigenous right to free, prior and informed consent (FPIC) — it is a right we are asserting, not something we can yet claim. This toolbox will elaborate on the rights local communities already have and those rights that still need to be recognised and enforced, to establish a Right to Say No.

The sunlight bids farewell to the mountains. The clouds hang in a sky tinged with pink and purple. The birds fly in flocks, returning to their trees. We, too, are returning home after another afternoon spent in the communal lands

We owe all children a planet Earth as wonderful as the one we have enjoyed!

Ce rapport analyse les obstacles et leviers à la lumière de projets inspirants en matière d'adaptation des villes à l'élévation du niveau de la mer dans le Pacifique.