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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
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
Abstract. Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC). Evidence-based decision-making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5–10 years, creating potential for an information gap between report cycles. We follow methods as close as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One (WGI) report. We compile monitoring datasets to produce estimates for key climate indicators related to forcing of the climate system: emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radiative forcing, the Earth's energy imbalance, surface temperature changes, warming attributed to human activit
We ran computer programs that simulate ecosystems 70,000 times and the results are very worrying.
An international team of scientists has warned against relying on nature providing straightforward 'early warning' indicators of a climate disaster, as new mathematical modeling shows new fascinating aspects of the complexity of the dynamics of climate. It suggests that the climate system could be more unpredictable than previously thought.
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
The planetary boundaries concept presents a set of nine planetary boundaries within which humanity can continue to develop and thrive for generations to come
A post for the anniversary of the execution of Sophie Scholl by the German Nazis in 1943
Anthropogenic emissions drive global-scale warming yet the temperature increase relative to pre-industrial levels is uncertain. Using 300 years of ocean mixed-layer temperature records preserved in sclerosponge carbonate skeletons, we demonstrate that industrial-era warming began in the mid-1860s, more than 80 years earlier than instrumental sea surface temperature records. The Sr/Ca palaeothermometer was calibrated against ‘modern’ (post-1963) highly correlated (R2 = 0.91) instrumental records of global sea surface temperatures, with the pre-industrial defined by nearly constant (<±0.1 °C) temperatures from 1700 to the early 1860s. Increasing ocean and land-air temperatures overlap until the late twentieth century, when the land began warming at nearly twice the rate of the surface oceans. Hotter land temperatures, together with the earlier onset of industrial-era warming, indicate that global warming was already 1.7 ± 0.1 °C above pre-industrial levels by 2020. Our result is 0.5 °C higher than IPCC estim
Here are the real reasons we’re not building clean energy anywhere near fast enough.
A crucial system of ocean currents may already be on course to collapse, according to a new report, with alarming implications for sea level rise and global weather — leading temperatures to plunge dramatically in some regions and rise in others. Using exceptionally complex and expensive computing systems, scientists found a new way to detect an early warning signal for the collapse of these currents, according to the study published Friday in the journal Science Advances. And as the planet warms, there are already indications it is heading in this direction.
Existing production destroys more value than it creates due to medical and environmental costs, researchers say
When Rishi Sunak granted 27 new North Sea licences this week, he wasn’t thinking about the survival of the living world, says Guardian columnist George Monbiot
Climate breakdown and crop losses threaten our survival, but the ultra-rich find ever more creative ways to maintain the status quo, says Guardian columnist George Monbiot
Around the world, rainforests are becoming savanna or farmland, savanna is drying out and turning into desert, and icy tundra is thawing. Indeed, scientific studies have now recorded "regime shifts" like these in more than 20 different types of ecosystem where tipping points have been passed. Around the world, more than 20% of ecosystems are in danger of shifting or collapsing into something different.
A major concern for the world’s ecosystems is the possibility of collapse, where landscapes and the societies they support change abruptly. Accelerating stress levels, increasing frequencies of extreme events and strengthening intersystem connections suggest that conventional modelling approaches based on incremental changes in a single stress may provide poor estimates of the impact of climate and human activities on ecosystems. We conduct xperiments on four models that simulate abrupt changes in the Chilika lagoon fshery, the Easter Island community, forest dieback and lake water quality—representing ecosystems with a range of anthropogenic interactions. Collapses occur sooner under increasing levels of primary stress but additional stresses and/or the inclusion of noise in all four models bring the collapses substantially closer to today by ~38–81%. We discuss the implications for further research and the need for humanity to be vigilant for signs that ecosystems are degrading even more rapidly than previo
Abstract. Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC), including the first global stocktake under the Paris Agreement that will conclude at COP28 in December 2023. Evidence-based decision-making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5–10 years, creating potential for an information gap between report cycles. We follow methods as close as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One (WGI) report. We compile monitoring datasets to produce estimates for key climate indicators related to forcing of the climate system: emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radia
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
Terrestrial ecosystems have taken up about 32% of the total anthropogenic CO2 emissions in the past six decades1. Large uncertainties in terrestrial carbon–climate feedbacks, however, make it difficult to predict how the land carbon sink will respond to future climate change2. Interannual variations in the atmospheric CO2 growth rate (CGR) are dominated by land–atmosphere carbon fluxes in the tropics, providing an opportunity to explore land carbon–climate interactions3–6. It is thought that variations in CGR are largely controlled by temperature7–10 but there is also evidence for a tight coupling between water availability and CGR11. Here, we use a record of global atmospheric CO2, terrestrial water storage and precipitation data to investigate changes in the interannual relationship between tropical land climate conditions and CGR under a changing climate. We find that the interannual relationship between tropical water availability and CGR became increasingly negative during 1989–2018 compared to 1960–1989
Global CO2 emissions for 2022 increased by 1.5% relative to 2021 (+7.9% and +2.0% relative to 2020 and 2019, respectively), reaching 36.1 GtCO2. These 2022 emissions consumed 13%–36% of the remaining carbon budget to limit warming to 1.5 °C, suggesting permissible emissions could be depleted within 2–7 years (67% likelihood).
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.
the biophysical limits of food production are being reached. Second, current food production systems are actively destroying the very resource base upon which they rely. Third, the majority of food production and all its storage and distribution is critically dependent upon fossil fuels, not only making the food supply vulnerable to price and supply instability, but also presenting an impossible choice between food security and reducing greenhouse gas emissions. Fourth, climate change is already negatively impacting the food supply and will do so with increasing intensity as the Earth continues to warm and weather destabilises. Fifth, the trajectory of increasing food demand that cannot easily be reversed. Sixth, the prioritisation of economic efficiency and profit in world trade has undermined food sovereignty and the resilience of food production at multiple scales, making both production and distribution highly vulnerable to disruptive shocks. Considered individually, each one of the hard trends presents a
An investigation by conservationists has found evidence that deep-seabed mining of rare minerals could cause “extensive and irreversible” damage to the planet.The report, to be published on Monday by the international wildlife charity Fauna & Flora, adds to the growing controversy that surrounds proposals to sweep the ocean floor of rare minerals that include cobalt, manganese and nickel. Mining companies want to exploit these deposits – which are crucial to the alternative energy sector – because land supplies are running low, they say.
Freshwater availability is changing worldwide. Here we quantify 34 trends in terrestrial water storage observed by the Gravity Recovery and Climate Experiment (GRACE) satellites during 2002–2016 and categorize their drivers as natural interannual variability, unsustainable groundwater consumption, climate change or combinations thereof. Several of these trends had been lacking thorough investigation and attribution, including massive changes in northwestern China and the Okavango Delta. Others are consistent with climate model predictions. This observation-based assessment of how the world’s water landscape is responding to human impacts and climate variations provides a blueprint for evaluating and predicting emerging threats to water and food security. Analysis of 2002–2016 GRACE satellite observations of terrestrial water storage reveals substantial changes in freshwater resources globally, which are driven by natural and anthropogenic climate variability and human activities.
By replacing thousands of equations with just one, ecology modelers can more accurately assess how close fragile environments are to a disastrous “tipping point.”
The steady destruction of wildlife can suddenly tip over into total ecosystem collapse, scientists studying the greatest mass extinction in Earth’s history have found. Many scientists think the huge current losses of biodiversity are the start of a new mass extinction. But the new research shows total ecosystem collapse is “inevitable”, if the losses are not reversed, the scientists said.
Folks who do systems analysis have a great belief in “leverage points.” These are places within a complex system (a corporation, an economy, a living body, a city, an ecosystem) where a small shift in one thing can produce big changes in everything.
La Niña is present.* Equatorial sea surface temperatures (SSTs) are below average across most of the Pacific Ocean. The tropical Pacific atmosphere is consistent with La Niña. La Niña is expected to continue into the winter, with equal chances of La Niña and ENSO-neutral during January-March 2023. In February-April 2023, there is a 71% chance of ENSO-neutral.*
The summary for policymakers (SPM) and the chapters of the Methodological assessment regarding the diverse conceptualization of multiple values of nature and its benefits, including biodiversity and ecosystem functions and services (referred to as the “assessment of the diverse values and valuation of nature”), were approved and accepted respectively by the IPBES Plenary during its ninth session, held from 3 to 9 July 2022 in Bonn, Germany. The background of this assessment dates to 2013, when at its second session (IPBES 2) in Antalya, Turkey, the IPBES Plenary approved the initiation of scoping for a methodological assessment. During the third session of the IPBES plenary, in Bonn, Germany in 2015, the expert group established for scoping the methodological assessment and developing a preliminary guide, was requested to revise the scoping report for the methodological assessment based on comments received following an open review by Governments and stakeholders. At IPBES 4, in Kuala Lumpur, Malaysia in 2016
Ember modelling of least-cost power system pathways reveals that a clean power system (70-80% wind and solar) by 2035 should be at the core of energy planning for a net-zero continent by mid-century.
