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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

This report describes the technical feasibility of creating mirror bacteria and the potentially serious and wide-ranging risks that they could pose to humans, other animals, plants, and the environment. It accompanies the Science Policy Forum article titled “Confronting risks of mirror life”, published December 12, 2024.

All known life is homochiral. DNA and RNA are made from “right-handed” nucleotides, and proteins are made from “left-handed” amino acids. Driven by curiosity and plausible applications, some researchers had begun work toward creating lifeforms composed entirely of mirror-image biological molecules. Such mirror organisms would constitute a radical departure from known life, and their creation warrants careful consideration. The capability to create mirror life is likely at least a decade away and would require large investments and major technical advances; we thus have an opportunity to consider and preempt risks before they are realized. Here, we draw on an in-depth analysis of current technical barriers, how they might be eroded by technological progress, and what we deem to be unprecedented and largely overlooked risks (1). We call for broader discussion among the global research community, policy-makers, research funders, industry, civil society, and the public to chart an appropriate path forward.

The big question: Would climate engineering like sending reflective particles into the stratosphere or brightening clouds help reduce the national security risks of climate change or make them worse?

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

Sharp declines in critical mineral prices mask risks of future supply strains as energy transitions advance - News from the International Energy Agency

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

Dangers of wildfires, extreme weather and other factors outgrowing preparedness, European Environment Agency says

In recent years, droughts have had substantial impacts on nearly all regions of the EU, affecting several critical systems such as agriculture, water supply, energy, river transport, and ecosystems. These impacts are projected to further increase due to climate change. While some of the drivers of drought risk are well known for some systems and regions, drought risks and impacts remain hard to assess and quantify. The European Drought Risk Atlas is a step towards impact-based drought assessment and can support the development and implementation of drought management and adaptation policies and actions. It characterises how drought hazard, exposure and vulnerability interact and affect different but interconnected systems: agriculture, public water supply, energy, riverine transport, freshwater and terrestrial ecosystems. The Atlas presents both a conceptual and quantitative approach to drought risk for these systems. The conceptual drought risk models (impact chains) are the result of a review of the literat

Policy-makers seeking to limit the impact of coal electricity-generating units (EGUs, also known as power plants) on air quality and climate justify regulations by quantifying the health burden attributable to exposure from these sources. We defined “coal PM2.5” as fine particulate matter associated with coal EGU sulfur dioxide emissions and estimated annual exposure to coal PM2.5 from 480 EGUs in the US. We estimated the number of deaths attributable to coal PM2.5 from 1999 to 2020 using individual-level Medicare death records representing 650 million person-years. Exposure to coal PM2.5 was associated with 2.1 times greater mortality risk than exposure to PM2.5 from all sources. A total of 460,000 deaths were attributable to coal PM2.5, representing 25% of all PM2.5-related Medicare deaths before 2009 and 7% after 2012. Here, we quantify and visualize the contribution of individual EGUs to mortality.

To prevent catastrophe, these countries must stop new extraction projects n: Just 20 countries, led overwhelmingly by the United States, Canada and Russia, are responsible for nearly 90 percent of new greenhouse gas emissions threatened by new oil and gas fields and fracking wells planned between now and 2050. If these extraction projects are allowed to proceed, they will lock in climate chaos and an unlivable future.

State Farm will almost entirely stop issuing new policies in California – with climate-exacerbated wildfires and bad public policy a large reason why

This innovative and comprehensive collection of essays explores the biggest threats facing humanity in the 21st century; threats that cannot be contained or controlled and that have the potential to bring about human extinction and civilization collapse. Bringing together experts from many disciplines, it provides an accessible survey of what we know about these threats, how we can understand them better, and most importantly what can be done to manage them effectively.

The role of health professionals In January 2023, the science and security board of the Bulletin of the Atomic Scientists moved the hands of the doomsday clock forward to 90 seconds before midnight, reflecting the growing risk of nuclear war.1 In August 2022, the UN secretary general, António Guterres, warned that the world is now in “a time of nuclear danger not seen since the height of the Cold War.”2 The danger has been underlined by growing tensions between many nuclear armed states.13 As editors of health and medical journals worldwide, we call on health professionals to alert the public and our leaders to this major danger to public health and the essential life support systems of the planet—and urge action to prevent it. Current nuclear arms control and non-proliferation efforts are inadequate to protect the world’s population against the threat of nuclear war by design, error, or miscalculation. The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) commits each of the 190 participating nations

Letter: Scientists and academics including Prof Gesa Weyhenmeyer and Prof Will Steffen argue that we must discuss the threat of societal disruption in order to prepare for it

Flash drought, characterized by unusually rapid drying, can have substantial impact on many socioeconomic sectors, particularly agriculture. However, potential changes to flash drought risk in a warming climate remain unknown. In this study, projected changes in flash drought frequency and cropland risk from flash drought are quantified using global climate model simulations. We find that flash drought occurrence is expected to increase globally among all scenarios, with the sharpest increases seen in scenarios with higher radiative forcing and greater fossil fuel usage. Flash drought risk over cropland is expected to increase globally, with the largest increases projected across North America (change in annual risk from 32% in 2015 to 49% in 2100) and Europe (32% to 53%) in the most extreme emissions scenario. Following low-end and medium scenarios compared to high-end scenarios indicates a notable reduction in annual flash drought risk over cropland. Flash droughts are projected to become more frequent unde

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Increasing risks posed by climate change are causing rare extreme events that can kill more than 10 million people or lead to damages of $10 trillion-plus, posing threats of total societal collapse, a UN report finds.

Words matter. It’s vital terms like ‘crisis’ and ‘calamity’ don’t become rhetorical devices devoid of real content as we argue about what climate action to take.