Evaluation of stratospheric transport in three generations of Chemistry-Climate Models Atmospheric Chemistry and Physics DOI 10.5194/acp-26-5249-2026 21 April 2026 Accurate representation of stratospheric transport in Chemistry-Climate Models is essential for reliable climate projections. This study evaluates three generations of models using observational data and reanalyses, identifying persistent biases and their potential causes. Some biases persist or even worsen in newer models. These findings highlight key limitations and inform efforts to improve models and advance understanding through process-based studies and enhanced observations. Read more
Interplay of North Atlantic freshening and deep convection during the last deglaciation constrained by Iberian speleothems Climate of the Past DOI 10.5194/cp-22-797-2026 20 April 2026 Stable isotope data of a precisely dated stalagmite from northwestern Iberia indicate gradual North Atlantic meltwater input during the last glacial maximum, followed by abrupt surges early in the last deglaciation. The first abrupt surge was decoupled from first cooling about 810 years later – unlike later events – which reveals that the Atlantic circulation’s sensitivity to meltwater is variable and related to the evolving background climate boundary conditions. Read more
Growth and decay of the Iceland Ice Sheet through the last glacial cycle Climate of the Past DOI 10.5194/cp-22-825-2026 17 April 2026 We simulated the Icelandic Ice Sheet over the last 120 kyr using an ice sheet model constrained by geological data with robust uncertainty assessment. At the Last Glacial Maximum, ice reached the continental shelf break, with a potential ice bridge connecting to the Greenland Ice Sheet. Model consistency with geological constraints during deglaciation is only possible with meltwater-driven ice fracture at the ice sheet margin, destabilizing the marine ice sheet and accelerating its collapse. Read more
Proglacial wetlands: an overlooked CO2 sink within recently deglaciated landscapes SOIL DOI 10.5194/soil-12-441-2026 17 April 2026 When glaciers retreat, new land surface is revealed. Using detailed glacial retreat maps, it is possible to determine for how long a location has been ice-free. That age is used in this study to analyse how fast carbon is incorporated into the soil. Our results show that the wetness of the soil strongly determines the CO2 uptake and carbon incorporation rates. Wetlands cover a small percentage of the land surface but are nonetheless important for the carbon storage in the deglaciated area. Read more
Drivers and implications of declining fossil fuel CO2 concentrations in Chinese cities revealed by radiocarbon measurements Atmospheric Chemistry and Physics DOI 10.5194/acp-26-5085-2026 16 April 2026 Our study indicates fossil fuel CO2 (CO2ff) reductions in Chinese megacities via atmospheric Δ(14CO2) and δ(13CO2) measurements, driven by coal-to-gas transitions and combustion efficiency improvement. The 24-year record show steeper declined urban RCO/CO2ff ratios than inventory estimates, implying underestimation of efficiency improvements and CO reductions. Integrating top-down observations with inventories is critical to track policy-driven emission shifts and optimize co-benefit strategies. Read more
Widespread occurrence of large molecular methylsiloxanes in ambient aerosols Atmospheric Chemistry and Physics DOI 10.5194/acp-26-5005-2026 16 April 2026 We identify a previously unrecognized class of synthetic organic compounds, large molecular methylsiloxanes, in ambient aerosols across diverse environments in three countries. These compounds are present at substantial levels, primarily originating from traffic emissions related to engine lubrication. Their high abundance and significant daily human exposure suggest potential, yet still poorly understood, implications for both health and climate. Read more
Geological factors and fracture distribution in deep and ultra-deep sandstones in Kuqa Depression, Tarim Basin, China Solid Earth DOI 10.5194/se-17-643-2026 15 April 2026 This study integrates geological and geophysical data to examine controls of sedimentary factors, earth stress, and tectonic structure on fracture distribution in deep and ultra-deep sandstones in Kuqa Depression. Key findings show fracture density increases with sandbody thickness and paleostress magnitude, is higher near faults and fold hinges, and is favored by thinner sand-mud interbeds. Increased horizontal stress differences contributes to reduced fracture apertures. Read more
Quiet New Particle Formation is a significant aerosol source in the Amazon boundary layer Atmospheric Chemistry and Physics DOI 10.5194/acp-26-4885-2026 14 April 2026 Aerosols are tiny particles that help clouds form and influence the climate. In the Amazon, clear events of new aerosol particle formation are rare, making it difficult to explain their origin. Using ten years of measurements, we discovered a subtle but frequent process called Quiet New Particle Formation. This hidden mechanism slowly produces and grows small particles and is responsible for nearly half of the smallest aerosols observed during the wet season. Read more
The Destination Earth digital twin for climate change adaptation Geoscientific Model Development DOI 10.5194/gmd-19-2821-2026 13 April 2026 The Climate Change Adaptation Digital Twin (Climate DT) pioneers the operationalisation of global climate projections. It produces global simulations with local granularity for adaptation decision-making. Applications are embedded to generate tailored indicators. A unified workflow orchestrates all components in several supercomputers. Data management ensures consistency and streaming enables real-time use. It is a complementary innovation to initiatives like CMIP, CORDEX, and climate services. Read more
Results of the second Ice Shelf–Ocean Model Intercomparison Project (ISOMIP+) The Cryosphere DOI 10.5194/tc-20-2053-2026 13 April 2026 The second Ice Shelf-Ocean Model Intercomparison Project, ISOMIP+, compares 12 ice shelf-ocean models with a common, idealised, static configuration, aiming to assess inter-model variability. Models show similar basal melt rate patterns, ocean profiles and circulation but differ in ice-ocean boundary layer properties. Ice-ocean boundary layer representation is a key area for future work, as are realistic-domain ice sheet-ocean model intercomparisons. Read more