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Experts warn that mirror bacteria, constructed from mirror images of molecules found in nature, could put humans, animals and plants at risk of lethal infections

A 1972 MIT study predicted that rapid economic growth would lead to societal collapse in the mid 21st century. A new paper shows we’re unfortunately right on schedule.

04/17/2024 - Even if CO2 emissions were to be drastically cut down starting today, the world economy is already committed to an income reduction of 19 % until 2050 due to climate change, a new study published in “Nature” finds. These damages are six times larger than the mitigation costs needed to limit global warming to two degrees. Based on empirical data from more than 1,600 regions worldwide over the past 40 years, scientists at the Potsdam Institute for Climate Impact Research (PIK) assessed future impacts of changing climatic conditions on economic growth and their persistence.

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

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.

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? 

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

We ran computer programs that simulate ecosystems 70,000 times and the results are very worrying.

As the Arctic warms, shrinking glaciers are exposing bubbling groundwater springs which could provide an underestimated source of the potent greenhouse gas methane, finds new research published in Nature Geoscience. The study, led by researchers from the University of Cambridge and the University Center in Svalbard, Norway, identified large stocks of methane gas leaking from groundwater springs unveiled by melting glaciers.

This Research Plan was prepared in response to a requirement in the joint explanatory statement accompanying Division B of the Consolidated Appropriations Act, 2022, directing the Office of Science and Technology Policy (OSTP), with support from the National Oceanic and Atmospheric Administration (NOAA), to provide a research plan for “solar and other rapid climate interventions.”

Several nations plan to build new coal power plants, with China alone approving nearly 100 gigawatts. Each gigawatt is the equivalent of installing more than 3 million solar panels.

Seafloor landforms reveal that ice sheets can collapse at 600 metres per day.

The new study shows that every increment of sea level rise will cover more than twice as much land as older models predicted, and marks another advance in providing more accurate models of rising seas

The destruction of global forests slowed in 2021 but the vital climate goal of ending deforestation by 2030 will still be missed without urgent action, according to an assessment. The area razed in 2021 fell by 6.3% after progress in some countries, notably Indonesia. But almost 7m hectares were lost and the destruction of the most carbon- and biodiversity-rich tropical rainforests fell by only 3%. The CO2 emissions resulting from the lost trees were equivalent to the emissions of the entire European Union plus Japan.

We have here (in the Baltic Sea, about half a million tonnes of conventional munitions and about 40,000 tonnes of chemical weapons. Some of the conventional munitions are armed and may explode if moved. As for poisoning people and fish, we don`t have enough data to speak of probability. However, the bombs leak poisonous substances, the seabed is contaminated in their immediate vicinity (up to 250 m).

The federal effort could set the stage for more studies into the feasibility, benefits and risks of one of the more controversial means of combating climate change.

Projected growth in rocket launches for space tourism, moon landings, and perhaps travel to According to new NOAA research published in the Journal of Geophysical Research Atmospheres, a 10-fold increase in hydrocarbon fueled launches, which is plausible within the next two decades based on recent trends in space traffic growth, would damage the ozone layer, and change atmospheric circulation patterns.

A liquified natural gas (LNG) crisis is brewing for European countries dealing with energy insecurity in the wake of Russia’s invasion of Ukraine, as demand will outstrip supply by the end of this year, Rystad Energy research shows. Although soaring demand has spurred the greatest rush of new LNG projects worldwide in more than a decade, construction timelines mean material relief is unlikely only after 2024. Global LNG demand is expected to hit 436 million tonnes in 2022, outpacing the available supply of just 410 million tonnes. A perfect winter storm may be forming for Europe as the continent seeks to limit Russian gas flows. The supply imbalance and high prices will set the scene for the most bullish environment for LNG projects in more than a decade, although supply from these projects will only arrive and provide relief from after 2024 The European Union’s REPowerEU plan has set an ambitious target to reduce dependence on Russian gas by 66% within this year – an aim that will clash with the EU’s goal of