Mapping the safe operating space of marine ecosystems under contrasting emission pathways Biogeosciences DOI 10.5194/bg-22-5435-2025 9 October 2025 Anthropogenic greenhouse gas emissions significantly impact ocean ecosystems through climate change and acidification, leading to either progressive or abrupt changes. This study maps the crossing of physical and ecological limits for various ocean impact metrics under three emission scenarios. Using Earth system models, we identify when these limits are exceeded, highlighting the urgent need for ambitious climate action to safeguard the world's oceans and ecosystems. Read more
Tipping points in ocean and atmosphere circulations Earth System Dynamics DOI 10.5194/esd-16-1611-2025 8 October 2025 In this work, we draw on palaeo-records, observations, and modelling studies to review tipping points in the ocean overturning circulations, monsoon systems, and global atmospheric circulations. We find indications for tipping in the ocean overturning circulations and the West African monsoon, with potentially severe impacts on the Earth system and humans. Tipping in the other considered systems is regarded as conceivable but is currently not sufficiently supported by evidence. Read more
Place-based science from Okinawa: 18th-century climate and geology recorded in Ryukyuan classical music Geoscience Communication DOI 10.5194/gc-8-251-2025 8 October 2025 Indigenous Ryukyuan music records the 18th-century climate and geology of the Ryukyu Kingdom (21st-century Okinawa Prefecture, Japan). By collaborating with Ryukyuan cultural practitioners, we find that two seafaring songs detail the winds, ocean currents, and volcanoes that historical voyagers faced during envoys to Kyushu, Japan. Educators can use such observations in place-based learning to increase environmental science engagement in 21st-century Okinawa and the Okinawan diaspora worldwide. Read more
Extensive fire-driven degradation in 2024 marks worst Amazon forest disturbance in over 2 decades Biogeosciences DOI 10.5194/bg-22-5247-2025 7 October 2025 The Amazon forest faces increasing wildfires due to extreme drought and human activity. In 2024, disturbances surged by 152 %, hitting a 20-year high. Forest degradation from fires grew by over 400 %, exceeding that from deforestation. Brazil and Bolivia were hit hardest. These fires released huge amounts of CO2, 7 times more than in recent years, pushing the Amazon towards a dangerous tipping point. Urgent action is needed to prevent irreversible harm. Read more
Increased future ocean heat uptake constrained by Antarctic sea ice extent Earth System Dynamics DOI 10.5194/esd-16-1453-2025 3 October 2025 Future projections of global ocean heat uptake (OHU) strongly differ between climate models. Here, we reveal an observational constraint on future OHU based on historical Antarctic sea ice extent observations. This emergent constraint is based on a coupling between sea ice, deep- and surface ocean temperatures, and cloud feedback. It implies an upward correction of 2024–2100 global OHU projections by up to 14 % and suggests that previous constraints have underestimated future warming. Read more
The coupled oxygen and carbon dynamics in the subsurface waters of the Gulf and Lower St. Lawrence Estuary and implications for artificial oxygenation Ocean Science DOI 10.5194/os-21-2179-2025 2 October 2025 We combine two decades of oxygen data with new carbon observations and a tracer-informed model to quantify oxygen loss and carbon buildup in the deep waters of the Gulf and Lower St. Lawrence Estuary. We then test a novel idea: reoxygenating these waters with the oxygen produced as a by-product from green-hydrogen production. Our results suggest this could significantly reduce hypoxia, though full recovery would require larger inputs. Read more
Insights from hailstorm track analysis in European climate change simulations Natural Hazards and Earth System Sciences DOI 10.5194/nhess-25-3693-2025 1 October 2025 Hailstorms can cause severe damage to homes, crops, and infrastructure. Using high-resolution climate simulations, we tracked thousands of hailstorms across Europe to study future changes. Large hail will become more frequent, hail-covered areas will expand, and instances of extreme hail combined with heavy rain will double. These shifts could increase risks for communities and businesses, highlighting the need for better preparedness and adaptation. Read more
Visualising historical changes in air pollution with the Air Quality Stripes Geoscience Communication DOI 10.5194/gc-8-229-2025 1 October 2025 The Air Quality Stripes images visualise historical changes in particulate matter air pollution in over 150 cities worldwide. The project celebrates significant improvements in air quality in regions like Europe, North America, and China while highlighting the urgent need for action in areas such as central Asia. Designed to raise awareness, the images aim to inspire discussions about the critical impact of air pollution and the global inequalities it causes. Read more
Food trade disruption after global catastrophes Earth System Dynamics DOI 10.5194/esd-16-1585-2025 30 September 2025 The global food trade system can handle small disturbances, but large disasters could cause major disruptions. We looked at how nuclear war or severe infrastructure loss would affect global trade in key crops. Both would be catastrophic, but a nuclear war would cause more severe disruptions, with many countries losing most of their food imports. Both scenarios highlight the need for better preparation to protect global food security. Read more
Physiological responses to ultra-high CO2 levels in an evergreen tree species Biogeosciences DOI 10.5194/bg-22-5069-2025 28 September 2025 As atmospheric CO2 increases globally, plants increase the rate of photosynthesis. Still, leaf–gas exchange can be downregulated by the plant. Here we tested the limits of these plant responses in a fruit tree species under very high CO2 levels relevant to the future Earth and to contemporary Mars. Plant water use decreased at 1600 ppm CO2 and remained low at 6000 ppm. Photosynthesis significantly increased at 6000 ppm. In summary, ultra-high CO2 may partly compensate for limited water availability. Read more