Livestock grazing, plant community and abiotic factors shape blue carbon stocks in Nordic coastal marshes Biogeosciences DOI 10.5194/bg-23-4583-2026 6 July 2026 Coastal marshes store high amounts of carbon but remain understudied in Nordic region. We measured organic carbon stored in plants and soil across grazed and ungrazed marshes along environmental gradients. Livestock grazing limited reed dominance, reduced aboveground carbon and altered roots allocation. Soil carbon was mainly controlled by soil properties rather than grazing at large scale. Our results show how grazing and environmental conditions jointly shape carbon storage in coastal marshes. Read more
In-depth characterisation of organic matter thermal lability and composition from Arctic Permafrost thaw slumps Biogeosciences DOI 10.5194/bg-23-4447-2026 3 July 2026 Abrupt permafrost thaw mobilizes ancient organic matter, which could fuel further warming, yet its fate remains uncertain. We studied thaw slumps in Arctic Canada using thermal, radiocarbon, and molecular analyses. Recently thawed debris and runoff exiting the slumps contained old, thermally stable organic matter, compositionally similar to surrounding permafrost. This suggests that much of the thaw-mobilised carbon survives initial transport and may be processed or sequestered downstream. Read more
Review article: The Foundation-Patuxent-Academy ice stream system, Antarctica The Cryosphere DOI 10.5194/tc-20-3705-2026 1 July 2026 We review research about a group of fast-flowing Antarctic ice streams, the Foundation-Patuxent-Academy System. Previously, we knew little about how these ice streams flow, how they interact with each other and the ocean, what their geological history was, and how they might evolve in a warming world. By reviewing existing research, we have identified the future research needed to determine how these ice streams function, and how they might contribute to future global sea level rise. Read more
Understanding changes in Iceland's streamflow dynamics in response to climate change Hydrology and Earth System Sciences DOI 10.5194/hess-30-3979-2026 30 June 2026 Iceland relies heavily on hydropower, making it important to understand changes in streamflow. Rivers reflect a warming, wetter climate, with rainfall increasingly replacing snowfall. Annual streamflow has generally increased, most notably during the cool season, while summer flows have declined in some non-glacial rivers. Glacial rivers show increasing melt-season flows over 1973–2023 but declining trends over 1993–2023, reflecting glacier retreat and recent North Atlantic sea surface cooling. Read more
Detection and attribution of the role of anthropogenic climate change in industrial-era retreat of Pine Island Glacier The Cryosphere DOI 10.5194/tc-20-3443-2026 30 June 2026 At least since we began measuring in detail, the West Antarctic Ice Sheet has lost a lot of ice, but we don't know precisely how important climate change is in this. Here, we put a number on the role of climate change in retreat of a glacier in this ice sheet, for the first time. We show that climate change made the shrinking of this glacier much worse. Our work also suggests that what happened on very long timescales (the last 10,000 years) might also matter for retreat of the ice sheets today. Read more
Quantification of inmixing of Asian Monsoon air by multi-species classification in a match flight experiment Atmospheric Chemistry and Physics DOI 10.5194/acp-26-9083-2026 29 June 2026 During the PHILEAS aircraft campaign a self-matching experiment was conducted to study the mixing of Asian Summer monsoon air into the upper troposphere – lower stratosphere. We present the first 3-D tomographic observations of this mixing for multiple trace gas species. We use advanced clustering to identify the types of air and their transport pathways, particularly into the stratosphere. Simulations of surface-origin tracers link several of these air types to different source regions. Read more
Climate models with moderate climate sensitivity best simulate the magnitude of Earth's energy imbalance Earth System Dynamics DOI 10.5194/esd-17-877-2026 29 June 2026 Observations show an increasing imbalance between how much energy the Earth absorbs from the Sun and emits back to space, leading to climate change. We evaluate how well climate models simulate both the magnitude and trend of the imbalance. We find that models capture the magnitude but underestimate the trend, which is not related to how models handle volcanic aerosols when switching to future scenarios. The models that best simulate the magnitude are the ones with moderate climate sensitivity. Read more
Air–Sea Interactions and Biogeochemical Responses to Medicane Daniel Biogeosciences DOI 10.5194/bg-23-4271-2026 26 June 2026 This study examines Medicane Daniel, showing how a warm-core eddy (WCE), high ocean heat content (OHC), and a marine heatwave (MHW) sustained its intensity near Libya. Using high-resolution Surface Water and Ocean Topography (SWOT) observations, we reveal fine-scale eddy dynamics and larger WCE structures than those captured by conventional datasets, highlighting their role in air–sea interactions. Enhanced moisture convergence supported storm intensification, while storm-induced mixing and upwelling increased chlorophyll, nutrient, and oxygen concentrations. Read more
Influence of tropospheric temperature on the formation and aging of secondary organic aerosol from biogenic vapor mixtures Atmospheric Chemistry and Physics DOI 10.5194/acp-26-8875-2026 24 June 2026 We investigate how temperature (213–313K) affects secondary organic aerosol (SOA) particles derived from isoprene and α-pinene mixtures. Isoprene's suppression on α-pinene dimer formation varied with temperatures. Particles formed at higher temperatures are more oxidized yet more volatile than those formed at lower temperatures and then warmed. This work highlights the need to consider both temperature and biogenic vapor interaction to accurately describe SOA formation, aging, and global burden. Read more
Estuarine mixing Ocean Science DOI 10.5194/os-22-1875-2026 22 June 2026 This review presents major aspects of estuarine mixing. Due to the large amounts of brackish water in estuaries produced by mixing of fresh river discharge and salty ocean water, mixing is one major characteristic of what is an estuary. Mixing is quantified locally as well as on estuary-wide scales. Diagnostics of integrated mixing are given for estuarine volumes bounded by transects as well as surfaces of constant salinity moving with the flow. Examples for real-world estuaries are given. Read more
Global and diurnal variations in tropospheric ammonia observed from a constellation of hyperspectral infrared sounders in three different LEO orbits Atmospheric Measurement Techniques DOI 10.5194/amt-19-4013-2026 19 June 2026 The diurnal cycle of NH3 remains under-constrained at a global scale. To address this gap, we construct an integrated constellation with hyperspectral infrared sounders in three different Low-Earth-Orbits to achieve quasi-geostationary-like global monitoring coverage of NH3 and provide six maps of global NH3 for every 4-hour in each day. This constellation has the potential to enhance the global climate-monitoring capacity of polar-orbiting meteorological satellites. Read more
Chaotic fluctuations in Greenland ice streams limit predictability of ice sheet collapse Earth System Dynamics DOI 10.5194/esd-17-769-2026 19 June 2026 This model study sets out to investigate how the collapse of the Greenland ice sheet to a virtually ice-free state due to increasing temperatures depends on the rate of this increase. We find oscillations in ice volume on millennial timescales that impact the time it takes before the ice sheet collapses, concluding that there is a mode of deterministic chaos internal to the ice sheet dynamics. Read more
Rapid soil degradation following deforestation in Eastern Africa Biogeosciences DOI 10.5194/bg-23-3907-2026 16 June 2026 Deforestation for croplands on tropical hillslopes causes severe soil degradation and loss of fertile topsoil. We found that this leads to a steep decline in soil fertility, including organic carbon, nitrogen, and phosphorus. This makes the land unproductive, often leading farmers to abandon it. Replanting with Eucalyptus trees doesn't restore fertility. This degradation leads to cropland lifespans of only 145±56 years and poses a serious threat to future food production. Read more
On describing particle nucleation within the Volatility Basis Set Atmospheric Chemistry and Physics DOI 10.5194/acp-26-8311-2026 15 June 2026 A new theory has the potential to accurately describe changes to atmospheric particle formation from the pre-industrial to the present and onwards along socioeconomic pathways addressing air pollution and climate. The model places organic nucleation in the context of the Volatility Basis Set and reveals a competition between chemistry, which accelerates as temperature rises, and vapor pressure, which drops as temperature decreases. The model reproduces observations from the CERN (European Organization for Nuclear Research) CLOUD (Cosmics Leaving Outdoor Droplets) chamber. Read more
Denitrification as the dominant process in nitrous oxide production in the water column of two eutrophic reservoirs Biogeosciences DOI 10.5194/bg-23-3887-2026 12 June 2026 Reservoirs act as nitrogen sinks and emit nitrous oxide, a potent greenhouse gas and major ozone-depleting substance. We studied two reservoirs and found that nitrification and denitrification produce nitrous oxide in the water column, but denitrification is the main source, fueled by fresh organic matter from phytoplankton. Our results also suggest that nitrous oxide is actively consumed. This study highlights the need to include reservoirs in global nitrous oxide budgets. Read more
Atmospheric river trajectories organise along a global transport network Earth System Dynamics DOI 10.5194/esd-17-695-2026 12 June 2026 Atmospheric rivers (ARs) move vast amounts of water through the atmosphere and often cause weather extremes, yet they are usually studied as regional events. Using 84 years of mapped AR trajectories, we reveal the global "roadmap" of ARs, a transport network of high-activity hubs, sparse atmospheric highways & hierarchical basins. Our approach shows how water vapor is systematically channelled through an atmospheric transport network, offering new ways to study changes in the global water cycle. Read more
Quantitative climate reconstruction from sedimentary ancient DNA: framework, validation and application Climate of the Past DOI 10.5194/cp-22-1159-2026 10 June 2026 We introduce a new climate proxy based on plant DNA preserved in lake sediments. Validated with a large surface sample dataset and applied to a sediment record, this method provides more accurate and robust reconstructions of past climate change than traditional vegetation proxies like pollen, likely due to a higher taxonomic resolution and more localized signal. Read more
The Pluvial Flood Index (PFI): a new instrument for evaluating flash flood hazards and facilitating real-time warning Natural Hazards and Earth System Sciences DOI 10.5194/nhess-26-2673-2026 10 June 2026 Pluvial (flash) floods, caused by intense local rainfall, result in surface runoff and overland flow, making them different from fluvial floods. A new Pluvial Flood Index (PFI) combines precipitation, hydrological, and hydrodynamic processes to assess surface flooding hazards. The PFI, based on flood hazard areas, helps forecast flash floods and supports real-time warning systems, aiding municipal decision-making, preparedness, and planning. Read more
The influence of ocean waves on Antarctic sea-ice albedo and seasonal melting, and potential coupled physical and biological feedbacks The Cryosphere DOI 10.5194/tc-20-3271-2026 9 June 2026 This paper advances understanding of why and how Antarctic sea ice can retreat so rapidly each summer, and identifies critical gaps in climate models, by highlighting 3 previously-neglected wave-driven processes and 5 associated feedbacks that accelerate seasonal ice melting and link physics to biology (wave flooding, wave pulverisation and wave greening). There are major implications for Earth’s radiation budget, Antarctic ecosystems and the accuracy of future sea-ice and climate projections. Read more
Wikimpacts 1.0: a new global climate impact database based on automated information extraction from Wikipedia Natural Hazards and Earth System Sciences DOI 10.5194/nhess-26-2609-2026 4 June 2026 Climate extremes threaten society and ecosystems, making impact understanding critical. Wikimpacts 1.0 provides an automated pipeline processing Wikipedia texts with underexploited information on climate impacts, yielding comprehensive socio-economic impact data for 2726 climate events from 1034–2024. It offers broader storm-related impacts and finer spatial resolution than established databases, showcasing natural language processing's potential to advance climate impact data. Read more