English references

For decades, the surface of the polar Southern Ocean (south of 50°S) has been freshening—an expected response to a warming climate. This freshening enhanced upper-ocean stratification, reducing the upward transport of subsurface heat and possibly contributing to sea ice expansion. It also limited the formation of open-ocean polynyas. Using satellite observations, we reveal a marked increase in surface salinity across the circumpolar Southern Ocean since 2015. This shift has weakened upper-ocean stratification, coinciding with a dramatic decline in Antarctic sea ice coverage. Additionally, rising salinity facilitated the reemergence of the Maud Rise polynya in the Weddell Sea, a phenomenon last observed in the mid-1970s.

Heatwaves can lead to considerable impacts on societal and natural systems. Accurate simulation of their response to warming is important for adaptation to potential climate futures. Here, we quantify changes of extreme temperatures worldwide over recent decades. We find an emergence of hotspots where the hottest temperatures are warming significantly faster than more moderate temperatures. In these regions, trends are largely underestimated in climate model simulations. Globally aggregated, we find that models struggle with both ends of the trend distribution, with positive trends being underestimated most, while moderate trends are well reproduced. Our findings highlight the need to better understand and model extreme heat and to rapidly mitigate greenhouse gas emissions to avoid further harm.

The startup Gigablue announced with fanfare this year that it reached a historic milestone: selling 200,000 carbon credits to fund what it describes as a groundbreaking technology in the fight against climate change . But outside scientists frustrated by the lack of information released by the company say serious questions remain about whether Gigablue’s technology works as the company describes. Their questions showcase tensions in an industry built on little regulation and big promises — and a tantalizing chance to profit.

Dozens of companies and academic groups are pitching the same theory: that sinking rocks, nutrients, crop waste or seaweed in the ocean could lock away climate-warming carbon dioxide for centuries or more. Nearly 50 field trials have taken place in the past four years, with startups raising hundreds of millions in early funds. But the field remains rife with debate over the consequences for the oceans if the strategies are deployed at large scale, and over the exact benefits for the climate. Critics say the efforts are moving too quickly and with too few guardrails.

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

CEOBS was launched in 2018 with the primary goal of increasing awareness and understanding of the environmental and derived humanitarian consequences of conflicts and military activities. In this, we seek to challenge the idea of the environment as a ‘silent victim of armed conflict’. Download our ‘About us‘ summary.

Major study finds world's most productive farming regions are especially vulnerable to rising temperatures, and face steep declines in agricultural output this century.

In a rapidly changing climate, evidence-based decision-making benefits from up-to-date and timely information. Here we compile monitoring datasets (published at https://doi.org/10.5281/zenodo.15639576; Smith et al., 2025a) to produce updated estimates for key indicators of the state of the climate system: net 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 activities, the remaining carbon budget, and estimates of global temperature extremes. This year, we additionally include indicators for sea-level rise and land precipitation change. We follow methods as closely as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One report.

Breaching threshold would ramp up catastrophic weather events, further increasing human suffering

SO2 declines have contributed ~25% of recent warming and driven recent acceleration. The impact of additional SO2 emissions on cloud formation diminishes as emissions increase, meaning that reductions in SO2 over areas with low background sulphate concentrations, such as the ocean, could result in a proportionately larger warming effect than in highly polluted areas, such as south Asia.

Mark Lynas has spent decades pushing for action on climate emissions but now says nuclear war is even greater threat Climate breakdown is usually held up as the biggest, most urgent threat humans pose to the future of the planet today. But what if there was another, greater, human-made threat that could snuff out not only human civilisation, but practically the entire biosphere, in the blink of an eye?

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.

Recent simulations using the Community Earth System Model (CESM) indicate that a tipping event of the Atlantic Meridional Overturning Circulation (AMOC) would cause Europe to cool by several degrees. This AMOC tipping event was found under constant pre-industrial greenhouse gas forcing, while global warming likely limits this AMOC-induced cooling response. Here, we quantify the European temperature responses under different AMOC regimes and climate change scenarios. A strongly reduced AMOC state and intermediate global warming (C, Representative Concentration Pathway 4.5) has a profound cooling effect on Northwestern Europe with more intense cold extremes. The largest temperature responses are found during the winter months and these responses are strongly influenced by the North Atlantic sea-ice extent. Enhanced North Atlantic storm track activity under an AMOC collapse results in substantially larger day-to-day temperature fluctuations. We conclude that the (far) future European temperatures are dependent o

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

2024 was the first single year to surpass the 1.5°C global warming threshold – now scientists predict that a year above 2°C is possible in the near future

The Antarctic Circumpolar Current (ACC) is the world's strongest ocean current and plays a disproportionate role in the climate system due to its role as a conduit for major ocean basins. This current system is linked to the ocean's vertical overturning circulation, and is thus pivotal to the uptake of heat and CO2 in the ocean. The strength of the ACC has varied substantially across warm and cold climates in Earth's past, but the exact dynamical drivers of this change remain elusive. This is in part because ocean models have historically been unable to adequately resolve the small-scale processes that control current strength. Here, we assess a global ocean model simulation which resolves such processes to diagnose the impact of changing thermal, haline and wind conditions on the strength of the ACC. Our results show that, by 2050, the strength of the ACC declines by ∼20% for a high-emissions scenario. This decline is driven by meltwater from ice shelves around Antarctica, which is exported to lower latit

Earth’s albedo (reflectivity) declined over the 25 years of precise satellite data, with the decline so large that this change must be mainly reduced reflection of sunlight by clouds. Part of the cloud change is caused by reduction of human-made atmospheric aerosols, which act as condensation nuclei for cloud formation, but most of the cloud change is cloud feedback that occurs with global warming. The observed albedo change proves that clouds provide a large, amplifying, climate feedback. This large cloud feedback confirms high climate sensitivity, consistent with paleoclimate data and with the rate of global warming in the past century.

Springtails illustrate in new research how global warning and antibiotic resistance creates synergistic effects: warming increases pesticide toxicity, triggering antibiotic resistance which spreads through horizontal gene transfer and predation.

2023 set a number of alarming new records. The global mean temperature also rose to nearly 1.5 degrees Celsius above the preindustrial level, another record.A team led by the Alfred Wegener Institute puts forward a possible explanation for the rise in global mean temperature: our planet has become less reflective because certain types of clouds have declined. The work is published in the journal Science.