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août 2024

SAO PAULO, Aug 1 (Reuters) - The number of fires in Brazil's Amazon rainforest region surged to a record high for the month of July in almost two decades, government data showed on Thursday, amid a drought in the region fanned by climate change. The Amazon, the world's largest rainforest, plays a vital role in curbing global warming because of the vast amounts of greenhouse gas it absorbs.
Unprecedented wildfires in Canada and parts of Amazonia last year were at least three times more likely due to climate change and contributed to high levels of CO2 emissions from burning globally, according to the first edition of a new systematic annual review.
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
The floods displaced more than 80,000 people, led to over 150,000 being injured and, on the 29th of May, to 169 fatalities with 44 people still missing (Governo do Estado de Rio Grande do Sul, 2024). Essential services were also disrupted, leaving 418,200 households without electricity and over a million consumer units without water. Dozens of municipalities lost telephone and internet services.
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
From farmers to disaster survivors, new plaintiffs and progressing lawsuits are putting pressure on industry polluters.
The airline blamed difficulties securing more efficient aircraft and sustainable jet fuel.
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%.

juillet 2024

The contaminants have also recently been found in testes and semen amid concerns about falling male fertility
Jakarta’s subsidence crisis illustrates the conflation of two threats: global climatic sea-level rise and the local environmental crisis. It also sheds light on the city’s longstanding issues of urban flooding and chronic piped water supply shortages.
As the climate crisis causes heavier and more frequent floods across the US, one in four small businesses are one disaster away from shutting down
Breathless reporting on when the present global heat anomaly will begin to fall is understandable, given heat suffering around the world. However, fundamental issues are in question and a reflection on time scales is in order, for the sake of understanding ongoing climate change and actions that need to be taken.
A carbon bomb is any fossil fuel extraction project that will generate more than one gigatonne of carbon dioxide (1GtCO2) over its remaining life.
Simultaneous harvest failures across major crop-producing regions are a threat to global food security. Concurrent weather extremes driven by a strongly meandering jet stream could trigger such events, but so far this has not been quantified. Specifically, the ability of state-of-the art crop and climate models to adequately reproduce such high impact events is a crucial component for estimating risks to global food security. Here we find an increased likelihood of concurrent low yields during summers featuring meandering jets in observations and models. While climate models accurately simulate atmospheric patterns, associated surface weather anomalies and negative effects on crop responses are mostly underestimated in bias-adjusted simulations. Given the identified model biases, future assessments of regional and concurrent crop losses from meandering jet states remain highly uncertain. Our results suggest that model-blind spots for such high-impact but deeply-uncertain hazards have to be anticipated and acc

juin 2024

If currently implemented policies are continued with no increase in ambition, there is a 90% chance that the Earth will warm between 2.3°C and 4.5°C, with a best estimate of 3.5°C.
“Timeless, masterful. . .A stomach-clenching, multi-perspective, ticking-clock, geopolitical thriller. Jacobsen expertly delivers a madman’s portrait of Armageddon, one made all the more impactful by the thought that it could literally occur at any moment. Almost novel-like in its presentation, Nuclear War: A Scenario represents the equivalent of an existential gut punch, a sickening and necessary reminder of how fragile every 21st century convenience becomes in the face of a blinding flash of light and near-instantaneous shockwave. Exhaustively researched and featuring interviews with professionals who truly understand just how close we continue to creep toward thermonuclear annihilation Nuclear War: A Scenario should be required reading for everyone alive today, especially for the politicians and policymakers who literally hold the precarious fate of our species in their hands.” — Forbes

mai 2024

In recent months we have seen lifechanging technological advances in the capabilities and use of artificial intelligence. At the same time, we are witnessing new, life-threatening risks as a result of AI – from the propagation of disinformation, to mass surveillance, to the prospect of lethal autono
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 ‘
Climate Obstruction Across Europe, coordinated by the Climate Social Science Network (CSSN) and published via Oxford University Press, reveals extensive networks impeding climate action within the region and surrounding states. In Italy and Germany, far-right networks spread misinformation by questioning climate science’s validity, while in Spain and the UK, blame-shifting and deflecting responsibility for climate action are common. European-based fossil fuel industries, like Shell, engage in greenwashing, by framing gas as a ‘bridging technology crucial for the energy transition’, delaying genuine progress.
Cultured meat is an emerging biotechnology that aims to produce meat from animal cell culture, rather than from the raising and slaughtering of livestock, on environmental and animal welfare grounds. The detailed understanding and accurate manipulation of cell biology are critical to the design of cultured meat bioprocesses. Recent years have seen significant interest in this field, with numerous scientific and commercial breakthroughs. Nevertheless, these technologies remain at a nascent stage, and myriad challenges remain, spanning the entire bioprocess. From a cell biological perspective, these include the identification of suitable starting cell types, tuning of proliferation and differentiation conditions, and optimization of cell–biomaterial interactions to create nutritious, enticing foods. Here, we discuss the key advances and outstanding challenges in cultured meat, with a particular focus on cell biology, and argue that solving the remaining bottlenecks in a cost-effective, scalable fashion will req
Winter downpours also made 20% wetter and will occur every three years without urgent carbon cuts, experts warn
Sharp declines in critical mineral prices mask risks of future supply strains as energy transitions advance - News from the International Energy Agency
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.
Global Report on Food Crises (GRFC) 2024
Exclusive: Survey of hundreds of experts reveals harrowing picture of future, but they warn climate fight must not be abandoned
Editorial: Top experts believe global temperatures will rise by at least 2.5C above pre-industrial levels by 2100. That frightening prediction must spur us to action
Unesco joint research dating back 15 years found violence and intimidation against about 750 reporters and 44 murders

avril 2024

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