références en Anglais

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

Mitigating climate change necessitates global cooperation, yet global data on individuals’ willingness to act remain scarce. In this study, we conducted a representative survey across 125 countries, interviewing nearly 130,000 individuals. Our findings reveal widespread support for climate action. Notably, 69% of the global population expresses a willingness to contribute 1% of their personal income, 86% endorse pro-climate social norms and 89% demand intensified political action. Countries facing heightened vulnerability to climate change show a particularly high willingness to contribute. Despite these encouraging statistics, we document that the world is in a state of pluralistic ignorance, wherein individuals around the globe systematically underestimate the willingness of their fellow citizens to act. This perception gap, combined with individuals showing conditionally cooperative behaviour, poses challenges to further climate action. Therefore, raising awareness about the broad global support for climat

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.

Dear COP 28 President-Designate Sultan Ahmed Al-Jaber, This year, world leaders gathering in the UAE to take stock of their climate commitments will for the first time engage in official programming focused on health. We, the signatories of this letter, support your leadership in bringing health front and center at COP28.

Ocean-driven melting of floating ice-shelves in the Amundsen Sea is currently the main process controlling Antarctica’s contribution to sea-level rise. Using a regional ocean model, we present a comprehensive suite of future projections of ice-shelf melting in the Amundsen Sea. We find that rapid ocean warming, at approximately triple the historical rate, is likely committed over the twenty-first century, with widespread increases in ice-shelf melting, including in regions crucial for ice-sheet stability. When internal climate variability is considered, there is no significant difference between mid-range emissions scenarios and the most ambitious targets of the Paris Agreement. These results suggest that mitigation of greenhouse gases now has limited power to prevent ocean warming that could lead to the collapse of the West Antarctic Ice Sheet. The authors use a regional ocean model to project ocean-driven ice-shelf melt in the Amundsen Sea. Already committed rapid ocean warming drives increased melt, regard

Mass extinctions during the past 500 million y rapidly removed branches from the phylogenetic tree of life and required millions of years for evolution to generate functional replacements for the extinct (EX) organisms. Here we show, by examining 5,400 vertebrate genera (excluding fishes) comprising 34,600 species, that 73 genera became EX since 1500 AD. Beyond any doubt, the human-driven sixth mass extinction is more severe than previously assessed and is rapidly accelerating. The current generic extinction rates are 35 times higher than expected background rates prevailing in the last million years under the absence of human impacts. The genera lost in the last five centuries would have taken some 18,000 y to vanish in the absence of human beings. Current generic extinction rates will likely greatly accelerate in the next few decades due to drivers accompanying the growth and consumption of the human enterprise such as habitat destruction, illegal trade, and climate disruption. If all now-endangered genera

Planetary Boundaries - summary and implications for policymakers 05.12.2022 Respecting planetary boundaries is essential to preserve the stability of ecosystems and human societies, including in Switzerland. Incorporating this principle into our legal system is consistent with the pursuit of our ...

For the first time, an international team of scientists is able to provide a detailed outline of planetary resilience by mapping out all nine boundary processes that define a safe operating space for humanity.

This planetary boundaries framework update finds that six of the nine boundaries are transgressed, suggesting that Earth is now well outside of the safe operating space for humanity. Ocean acidification is close to being breached, while aerosol loading regionally exceeds the boundary. Stratospheric ozone levels have slightly recovered. The transgression level has increased for all boundaries earlier identified as overstepped. As primary production drives Earth system biosphere functions, human appropriation of net primary production is proposed as a control variable for functional biosphere integrity. This boundary is also transgressed. Earth system modeling of different levels of the transgression of the climate and land system change boundaries illustrates that these anthropogenic impacts on Earth system must be considered in a systemic context.

Poly- and perfluoroalkyl substances (PFAS) and global climate change have attracted worldwide attention. PFAS have been found all across the planet, from the polar regions to the global ocean. Global oceans have emerged as a substantial sink for the carbon in the environment due to their remarkable capacity to absorb atmospheric carbon. Oceans absorb around 24% of the world’s CO2 emissions. Thus, the ocean plays a prominent role in the earth’s carbon cycle. However, the widespread application of PFAS in a wide range of products and the inefficient management of PFAS-containing wastes made them ubiquitous pollutants, which are increasingly getting as a pollutant of emerging concern. Marine PFAS pollutants can produce harmful effects on gas exchange and the ocean’s carbon cycle. Thus, it leads to an increase in greenhouse gas emissions, which eventually adversely affects global warming and climate change. Consequently, threats of marine PFAS to oceans carbon sequestration are discussed in this paper. Marine PFA

The Atlantic meridional overturning circulation (AMOC) is a major tipping element in the climate system and a future collapse would have severe impacts on the climate in the North Atlantic region. In recent years weakening in circulation has been reported, but assessments by the Intergovernmental Panel on Climate Change (IPCC), based on the Climate Model Intercomparison Project (CMIP) model simulations suggest that a full collapse is unlikely within the 21st century. Tipping to an undesired state in the climate is, however, a growing concern with increasing greenhouse gas concentrations. Predictions based on observations rely on detecting early-warning signals, primarily an increase in variance (loss of resilience) and increased autocorrelation (critical slowing down), which have recently been reported for the AMOC. Here we provide statistical significance and data-driven estimators for the time of tipping. We estimate a collapse of the AMOC to occur around mid-century under the current scenario of future emi

Plastic debris is thought to be widespread in freshwater ecosystems globally1. However, a lack of comprehensive and comparable data makes rigorous assessment of its distribution challenging2,3. Here we present a standardized cross-national survey that assesses the abundance and type of plastic debris (>250 μm) in freshwater ecosystems. We sample surface waters of 38 lakes and reservoirs, distributed across gradients of geographical position and limnological attributes, with the aim to identify factors associated with an increased observation of plastics. We find plastic debris in all studied lakes and reservoirs, suggesting that these ecosystems play a key role in the plastic-pollution cycle. Our results indicate that two types of lakes are particularly vulnerable to plastic contamination: lakes and reservoirs in densely populated and urbanized areas and large lakes and reservoirs with elevated deposition areas, long water-retention times and high levels of anthropogenic influence. Plastic concentrations vary

Although humans have long been predators with enduring nutritive and cultural relationships with their prey, seldom have conservation ecologists considered the divergent predatory behavior of contemporary, industrialized humans. Recognizing that the number, strength and diversity of predator-prey relationships can profoundly influence biodiversity, here we analyze humanity’s modern day predatory interactions with vertebrates and estimate their ecological consequences. Analysing IUCN ‘use and trade’ data for ~47,000 species, we show that fishers, hunters and other animal collectors prey on more than a third (~15,000 species) of Earth’s vertebrates. Assessed over equivalent ranges, humans exploit up to 300 times more species than comparable non-human predators. Exploitation for the pet trade, medicine, and other uses now affects almost as many species as those targeted for food consumption, and almost 40% of exploited species are threatened by human use. Trait space analyses show that birds and mammals threaten

Heat and cold are now established health risk factors, with several studies reporting important mortality effects in populations around the world.1, 2, 3 The associated health burden is expected to increase with climate change, especially under the most extreme scenarios of global warming.4, 5 However, robust estimates of excess mortality in the current and future periods are still challenging to obtain due to the numerous factors influencing vulnerability to heat and cold, including climatic, environmental, and socioeconomic conditions.6 These factors represent the main drivers of variation in mortality risks, which have been shown to differ geographically and across age groups.

The stability and resilience of the Earth system and human well-being are inseparably linked1–3, yet their interdependencies are generally under-recognized; consequently, they are often treated independently4,5. Here, we use modelling and literature assessment to quantify safe and just Earth system boundaries (ESBs) for climate, the biosphere, water and nutrient cycles, and aerosols at global and subglobal scales. We propose ESBs for maintaining the resilience and stability of the Earth system (safe ESBs) and minimizing exposure to significant harm to humans from Earth system change (a necessary but not sufficient condition for justice)4. The stricter of the safe or just boundaries sets the integrated safe and just ESB. Our findings show that justice considerations constrain the integrated ESBs more than safety considerations for climate and atmospheric aerosol loading. Seven of eight globally quantified safe and just ESBs and at least two regional safe and just ESBs in over half of global land area are alrea

Improved knowledge of glacial-to-interglacial global temperature change implies that fastfeedback equilibrium climate sensitivity (ECS) is 1.2 ± 0.3°C (2σ) per W/m2 . Consistent analysis of temperature over the full Cenozoic era – including “slow” feedbacks by ice sheets and trace gases – supports this ECS and implies that CO2 was about 300 ppm in the Pliocene and 400 ppm at transition to a nearly ice-free planet, thus exposing unrealistic lethargy of ice sheet models. Equilibrium global warming including slow feedbacks for today’s human-made greenhouse gas (GHG) climate forcing (4.1 W/m2) is 10°C, reduced to 8°C by today’s aerosols. Decline of aerosol emissions since 2010 should increase the 1970-2010 global warming rate of 0.18°C per decade to a post-2010 rate of at least 0.27°C per decade. Under the current geopolitical approach to GHG emissions, global warming will likely pierce the 1.5°C ceiling in the 2020s and 2°C before 2050. Impacts on people and nature will accelerate as global warming pumps up hydr

Climate change has important implications for the health and futures of children and young people, yet they have little power to limit its harm, making them vulnerable to climate anxiety. This is the first large-scale investigation of climate anxiety in children and young people globally and its relationship with perceived government response.

The WFPHA proposes to lead a discussion about global aid and Global Health Initiatives (GHIs), beginning in these Federation Pages. In this issue (JPHP 31.1), we have invited authors from the Department of Public Health from the Institute of Tropical Medicine Antwerp, Belgium, and from the Federal Ministry of Health, Addis Ababa, Ethiopia to discuss the ‘New dichotomy in health systems’ strengthening and the role of global health initiatives’. Next, the WFPHA will take a very active part in the upcoming Geneva Forum, 19–21 April 2010, entitled Globalization, Crisis & Health Systems: Confronting Regional Perspectives (http://www.ghf10.org/). The problems of GHIs will be the topic of a special session. In it, the organisers will integrate views of researchers, such as the contributors here, along with those of GHIs professionals, and participants from recipient countries.

We are writing to urge you to push the United Arab Emirates to withdraw the appointment of Sultan Al Jaber, head of the Abu Dhabi National Oil Company, as President-designate of the United Nations Framework Convention on Climate Change Conference of Parties 28 (COP 28). The decision to name the chief executive of one of the world’s largest oil and gas companies as president of the next U.N. Climate Change Conference risks jeopardizing climate progress from successive U.N. Climate Conferences. To help ensure that COP 28 is a serious and productive climate summit, we believe the United States should urge the United Arab Emirates to name a different lead for COP 28 or, at a minimum, seek assurances that it will promote an ambitious COP 28 aligned with the 1.5 degrees Celsius limit and Intergovernmental Panel on Climate Change (IPCC) findings and take concrete steps to demonstrate domestic and regional leadership toward this end.

Soils are known to be an enormous reservoir of carbon and represent an important and dynamic part of the global carbon cycle. However, this reservoir is under constant threat due to a combination of issues, including mismanagement, climate change and intensive agricultural production which has led to depletion of soil organic carbon. Understanding and fostering soil carbon sequestration reviews the wealth of research on important aspects of soil carbon sequestration, including its potential in mitigating and adapting to climate change and improving global food security. The collection explores our understanding of carbon sequestration in soils, detailing the mechanisms and abiotic factors that can affect the process, as well as the socioeconomic, legal and policy issues that can arise as a result of this use. In its extensive exploration of soil carbon cycling and capture, the book highlights how an informed understanding of carbon sequestration in a variety of soil types can contribute to achieving a more su

Climate change affects the Arctic and sub-Arctic regions by exposing previously frozen permafrost to thaw, unlocking soil nutrients, changing hydrological processes, and boosting plant growth. As a result, sub-Arctic tundra is subject to a shrub expansion, called “shrubification”, at the expense of sedge species. Depending on the intrinsic foliar properties of these plant species, changes in foliar mineral element fluxes with shrubification in the context of permafrost degradation may influence topsoil mineral element composition. Despite the potential implications of changes in topsoil mineral element concentrations for the fate of organic carbon, this remains poorly quantified. Here, we investigate vegetation foliar and topsoil mineral element composition (Si, K, Ca, P, Mn, Zn, Cu, Mo, V) across a natural gradient of permafrost degradation at a typical sub-Arctic tundra at Eight Mile Lake (Alaska, USA). Results show that foliar mineral element concentrations are higher (up to 9 times; Si, K, Mo for all spec

Improved knowledge of glacial-to-interglacial global temperature change implies that fast- feedback equilibrium climate sensitivity is at least ~4°C for doubled CO2 (2×CO2), with likely range 3.5-5.5°C. Greenhouse gas (GHG) climate forcing is 4.1 W/m2 larger in 2021 than in 1750, equivalent to 2×CO2 forcing. Global warming in the pipeline is greater than prior estimates. Eventual global warming due to today’s GHG forcing alone – after slow feedbacks operate – is about 10°C. Human-made aerosols are a major climate forcing, mainly via their effect on clouds. We infer from paleoclimate data that aerosol cooling offset GHG warming for several millennia as civilization developed. A hinge-point in global warming occurred in 1970 as increased GHG warming outpaced aerosol cooling, leading to global warming of 0.18°C per decade. Aerosol cooling is larger than estimated in the current IPCC report, but it has declined since 2010 because of aerosol reductions in China and shipping. Without unprecedented global actions to

This full length briefing explains what Non-Economic Loss and Damage (NELD) is, why and how it happens, where it happens, who is most affected, and importantly how it can be addressed. Featuring case studies from both the Global North and South, the brief captures the latest thinking on NELD all in one place whilst acting as an accessible introduction for those new to the topic.

Mapped: How climate change affects extreme weather around the world

Today, the average global temperature has increased by more than 1°C compared to pre-industrial values (Figure 1-1); atmospheric CO2 concentrations have risen from 280 to more than 400 ppm. At the current pace of emissions, the carbon budget that is left for staying below the 2°C target of the Paris Agreement will be depleted in a few tens of years. For the 1.5°C target, this budget will be exhausted before the decade is out.