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Paul R. Ehrlich will be remembered as a scientist whose books about population and threats to the environment shaped the idea of limited growth in the modern era.
The Gulf Stream is part of the Atlantic Meridional Overturning Circulation (AMOC). The AMOC is a tipping element and may collapse under changing forcing. However, the role of the Gulf Stream in such a tipping event is unknown. Here, we investigate the link between the AMOC and Gulf Stream using a high-resolution (0. 1°) stand-alone ocean simulation, in which the AMOC collapses under a slowly-increasing freshwater forcing. AMOC weakening gradually shifts the Gulf Stream near Cape Hatteras northward, followed by an abrupt northward displacement of 219 km within 2 years. This rapid shift occurs a few decades before the simulated AMOC collapse. Satellite altimetry shows a significant (1993–2024, p < 0.05) northward Gulf Stream trend near Cape Hatteras, which is also confirmed in subsurface temperature observations (1965–2024, p < 0.01). These findings provide indirect evidence for present-day AMOC weakening and demonstrate that abrupt Gulf Stream shifts can serve as early warning indicator for AMOC tipping.
The growth rate of greenhouse gas (GHG) climate forcing increased rapidly in the last 15 years to about 0.5 W/m2 per decade, as shown by the “colorful chart” for GHG climate forcing that we have been publishing for 25 years (Fig. 1).[1] The chart is not in IPCC reports, perhaps because it reveals inconvenient facts. Although growth of GHG climate forcing declined rapidly after the 1987 Montreal Protocol, other opportunities to decrease climate forcing were missed. If policymakers do not appreciate the significance of present data on changing climate forcings, we scientists must share the blame.
Launched at the COP30 Belém Climate Summit, the Global Status of Multi-Hazard Early Warning Systems 2025 report provides a snapshot of progress in the implementation of the UN's flagship Early Warnings for All (EW4All) initiative, which aims to protect every person on Earth with an early warning system by 2027. The report reveals measurable progress, with 119 countries, or 60% of all countries, now reporting the existence of a Multi-Hazard Early Warning System. This is a 113% increase over the past 10 years. However, coverage gaps persist, especially among small island developing States, as only 43% of them reported having systems in place.
We propose a new paradigm, as toxicology currently lacks the proper perspective. From the 1950s to the 1970s, at least one-third of all toxicological testing in the United States, including for chemicals and drugs, was misleading scientists, and this worldwide issue persists today. Moreover, petroleum-based waste and heavy metals have been discovered in pesticide and plasticizer formulations. These contaminations have now reached all forms of life. Widespread exposure to chemical mixtures promotes health and environmental risks. We discovered that pesticides have never undergone long-term testing on mammals in their full commercial formulations by regulatory authorities or the pesticide industry; instead, only their declared active ingredients have been assessed, contrary to environmental law recommendations. The ingredients of these formulations are not fully disclosed, yet the formulations are in general at least 1000 times more toxic at low environmentally relevant doses than the active ingredients alone u
German scientists warn global warming is accelerating faster than expected, raising the risk of a 3 °C rise by 2050 and forcing Europe to confront unthinkable adaptation plans.
EU officials warn climate breakdown and wildlife loss ‘are ruining ecosystems that underpin the economy’ […] The European way of life is being jeopardised by environmental degradation, a report has found, with EU officials warning against weakening green rules. The continent has made “important progress” in cutting planet-heating pollution, according to the European Environment Agency, but the death of wildlife and breakdown of the climate are ruining ecosystems that underpin the economy.
Forever chemicals have polluted the water supply of 60,000 people, threatening human health, wildlife and the wider ecosystem. But activists say this is just the tip of the Pfas iceberg
Fifteen years ago, smack in the middle of Barack Obama's first term, amid the rapid rise of social media and a slow recovery from the Great Recession, a professor at the University of Connecticut issued a stark warning: the United States was heading into a decade of growing political instability.
There’s frustration among researchers that falling pH levels in seas around the globe are not being taken seriously enough, and that until the buildup of CO2 is addressed, the consequences for marine life will be devastating
A new study uncovers Earth’s deep temperature history and shows just how tightly carbon dioxide has always controlled the climate
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
the starkest warning yet that human activity is pushing Earth into a climate crisis that could threaten the lives of up to 6 billion people this century, stating candidly: “We are afraid of the uncharted territory that we have now entered.” Writing in the journal Biosciences, the coalition of 12 researchers, spanning North America, Europe and Asia, state in unusually stark language: “As scientists, we are increasingly being asked to tell the public the truth about the crises we face in simple and direct terms. The truth is that we are shocked by the ferocity of the extreme weather events in 2023.”
Previously, anthropogenic ecological overshoot has been identified as a fundamental cause of the myriad symptoms we see around the globe today from biodiversity loss and ocean acidification to the disturbing rise in novel entities and climate change. In the present paper, we have examined this more deeply, and explore the behavioural drivers of overshoot, providing evidence that overshoot is itself a symptom of a deeper, more subversive modern crisis of human behaviour. We work to name and frame this crisis as ‘the Human Behavioural Crisis’ and propose the crisis be recognised globally as a critical intervention point for tackling ecological overshoot. We demonstrate how current interventions are largely physical, resource intensive, slow-moving and focused on addressing the symptoms of ecological overshoot (such as climate change) rather than the distal cause (maladaptive behaviours). We argue that even in the best-case scenarios, symptom-level interventions are unlikely to avoid catastrophe or achieve more
The UN Secretary-General’s Early Warnings for All Initiative (EW4All) is rapidly gaining ground. Action plans are being rolled out around the world to ensure that people know when dangerous weather is headed their way. Tajikistan has held a two-day national consultation, co-chaired by the Deputy Prime Minister and the UN Resident Coordinator in Tajikistan, and bringing together key stakeholders from state and international organizations, media and civil society. Ethiopia also held an inception workshop.
Antarctica’s sea ice levels are plummeting as extreme weather events happen faster than scientists predicted
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
Humanity received a “final warning” Monday from the UN Intergovernmental Panel on Climate Change. The bottom line of the Synthesis Report of the IPCC’s Sixth Assessment Report is to “act now, or it’s too late,” the Guardian wrote. The scale of the emergency screams out from almost every page — climate change is already displacing and killing millions of people globally — but the report also provides what UN Secretary-General António Guterres called a roadmap for defusing the “climate time bomb.”
IPCC report says only swift and drastic action can avert irrevocable damage to world
There's no time for complacency, according to Dr. Peter Carter, founder of the Climate Emergency Institute
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