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août 2024

The temperatures of the Mediterranean Sea in recent days have reached heat records set last summer, the main Spanish maritime research center told AFP Tuesday, with marine heat waves in some places exceeding 30 degrees Celsius.
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
In Virginia, a small conservation group is leading the fight against the powerful and secretive data center industry.
UN says a global ‘backlash’ against climate action is being stoked by fossil fuel companies
Greece, Italy, Spain, Portugal, France and Morocco experienced extreme heat in July 2024, causing at least 23 fatalities, widespread wildfires and bringing public life to a hold.
Research shows climate change carries greater risks for unborn babies than previously thought. Some of the alarming effects of global warming may include worsening health and wellbeing in later life.
The story of Greenland keeps getting greener—and scarier. A new study provides the first direct evidence that the center—not just the edges—of Greenland's ice sheet melted away in the recent geological past and the now-ice-covered island was then home to a green, tundra landscape.
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 destruction de l'Amazonie est un phénomène qui s’étend au-delà de la déforestation mais les neuf pays qui partagent cette ressource naturelle sont engagés à la protéger.
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

Scientists now fear that there is little more than five years left to prevent irreversible climate damage and stark changes to the Earth’s weather patterns from global carbon emissions, Minister for Climate Eamon Ryan has warned.
Sudden cut in pollution in 2020 meant less shade from sun and was ‘substantial’ factor in record surface temperatures in 2023, study finds
Scientists warn of ‘scary’ feedback loop in which fires create more heating, which causes more fires worldwide
Small increase in temperature of intruding water could lead to very big increase in loss of ice, scientists say
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.
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.
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
Huge patches of forest in Tasmania have rapidly turned brown over recent months, with many trees dying after a dry summer. As climate change causes hotter and drier weather, can we expect more tree deaths in the future? 

juin 2024

Carbon Brief provides an updated analysis of when the world will likely exceed the Paris 1.5C limit
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.
Women and gender-diverse people bear the brunt of climate change’s negative affects. If Australia wants to be taken seriously on climate action, this needs addressing.

mai 2024

Insight and inspiration in turbulent times. People have widely varying beliefs about climate change. A surprising number still think that it’s a hoax, or that it’s a trivial problem. At the other end of the opinion spectrum, some say it signals the end of the world and there’s nothing we can do to stop it. Between those extremes are lots of folks who believe climate change is a serious dilemma, but we can deal with it by installing solar panels, nuclear power, solar radiation management technologies, and/or machines to remove carbon dioxide (CO2) from the atmosphere, after which we will continue to live mostly the way we do today.
This essay takes up and extends an analysis of the ambitions of the energy transition presented during the conference entitled “L’erreur fondamentale de la transition”, held in Lausanne in December 2022, at the annual Switzerland ShiftersDay. The intervention questioned the conceptualization of energy transition, given possible inaccuracies, or errors in the categorization of reality. It is not certain that the energy contained in the wind, solar radiation, or atoms is equivalent to hydrocarbon energy for human societalneeds. Although all energies are theoretically convertible into one another, the assumption that any type of energy can always be replaced by another is likely to prove false. An energy transition based on the substitution of energies would then be inconceivable.
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
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
Climate scientists have told the Guardian they expect catastrophic levels of global heating. Here’s what that would mean for the planet
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