In a groundbreaking study published in Nature Climate Change, scientists have uncovered a critical driver behind a high-latitude warming hotspot in the Southern Ocean—a phenomenon attributed to the complex interactions of ocean mesoscale eddies. The Southern Ocean is a vital component of the global climate system, playing a fundamental role in heat and carbon uptake, yet understanding its warming patterns remains a grand challenge due to the intricate interplay of oceanic and atmospheric processes.

Over the past four decades, from 1982 to 2023, observations have revealed a notable surface warming signal concentrated in certain regions of the Southern Ocean. To robustly characterize this warming, researchers employed a suite of state-of-the-art sea surface temperature (SST) datasets derived from multiple sources including NOAA’s Optimum Interpolated SST, ECMWF’s ORAS5 ocean reanalysis, NOAA’s Extended Reconstructed SST, the Institute of Atmospheric Physics surface temperature records, and the high-resolution Met Office OSTIA product. These datasets, varying in spatial resolution from 0.05° to 2°, collectively ensure a detailed and reliable representation of temperature trends despite the Southern Ocean’s formidable observational challenges.

Beneath the surface, the temperature structure and mixed layer depth have been meticulously analyzed using the extensive Argo float network, which provides high-resolution data from 2004 to 2023. By calculating the mixed layer depth through the vertical buoyancy frequency maximum method, the team achieved a consistent and physically meaningful depiction of how the upper ocean stratification evolves in the warming hotspot region. This approach also aligns well with other established methods, lending further confidence to the interpretation of subsurface heat dynamics.

One of the study’s fundamental breakthroughs involved the incorporation of satellite-observed daily surface geostrophic currents to calculate eddy kinetic energy (EKE)—a critical measure of the ocean’s mesoscale variability. Geostrophic currents at a fine spatial resolution of 0.125° were segmented into mean flows (3-month averages) and perturbations representing eddies. Through careful analysis of these perturbations, the researchers quantified how mesoscale eddies contribute to the Southern Ocean’s thermal state, elucidating their pivotal role not just as passive features but as active agents in heat redistribution.

Additionally, satellite-based chlorophyll-a concentration data spanning 1998 to 2023 was leveraged to assess biological responses to warming. Chlorophyll serves as a proxy for phytoplankton biomass, which is highly sensitive to changes in upper ocean temperature and mixing. This integrated biophysical perspective enables the researchers to frame the warming process within broader ecological implications, an essential step toward comprehensive climate impact assessments.

To understand the mechanisms driving the observed warming hotspot, the scientists turned to high-resolution climate simulations using the Community Earth System Model-High Resolution (CESM-HR). This model components include coupled representations of the atmosphere, ocean, sea ice, and land, simulated at nominally eddy-resolving horizontal resolutions of 0.1° for the ocean and sea ice and 0.25° for atmosphere and land. Following the Coupled Model Intercomparison Project Phase 5 protocol, CESM-HR runs enable the dissection of key physical processes at unprecedented scales previously unreachable in global climate models.

The CESM-HR simulation strategy included two experimental setups: the pre-industrial control (PI-CTRL), representing a stable climate baseline, and a historical-forcing simulation incorporating time-varying anthropogenic influences up to 2100 under RCP8.5, known as HF-TNST. By calibrating trends to exclude model drifts through comparisons with the PI-CTRL, the authors ensured that derived long-term warming signals authentically represent climate change impacts, thereby enhancing the robustness of the mechanistic findings pertinent to the upper Southern Ocean’s response.

A pivotal analytical tool was the partitioning of mean flows and mesoscale eddies, defined by deviations from 3-month averaged states. This allowed precise quantification of the roles played by mean circulation and eddy-induced heat transport. Such decomposition revealed that mesoscale eddies significantly modulate the convergence of heat transport within the warming hotspot, fundamentally altering thermal stratification and surface temperature trends.

The heart of the study’s analysis lies within the vertically averaged ocean heat budget framework. This diagnostic equation encapsulates the change in temperature within the water column as a balance between heat convergence by mean flows, heat convergence by eddies, surface heat fluxes, and turbulent mixing processes. In meticulous detail, the researchers computed these terms directly from model outputs, with turbulent mixing inferred as a residual term. Their quantitative assessment pinpoints mesoscale eddies as not mere bystanders but as key contributors to heat redistribution, exerting a critical influence on regional warming patterns.

Further mechanistic insight was achieved through the computation of the conversion from mean available potential energy (MAPE) to eddy available potential energy (EAPE), a dynamical energy exchange indicative of baroclinic instability—the process through which energy stored in mean density gradients transfers to eddy fields. Utilizing daily velocity, temperature, and salinity from selected periods when fine-scale model outputs are available, the study convincingly demonstrates enhanced energy conversions under warming scenarios. This intensification of baroclinic instability facilitates stronger eddy generation and thus more vigorous vertical eddy heat transport.

The cascade of energy from MAPE to EAPE and subsequently to eddy kinetic energy (EKE) underscores the vital role of mesoscale eddies in modulating Southern Ocean warming. The amplified vertical eddy heat transport identified by the research signifies a dynamic ocean adjustment process that not only shapes temperature evolution but also likely impacts nutrient fluxes, carbon cycling, and sea ice distribution in polar regions.

This study represents a significant advancement in oceanographic climate science by unequivocally linking mesoscale eddy dynamics to observed high-latitude Southern Ocean warming hotspots. Beyond enriching our conceptual understanding, these findings underscore the necessity of resolving ocean mesoscale processes in global climate models. Such resolution is essential for credible projections of polar climate change, which carry profound implications for global sea level rise, weather patterns, and carbon sequestration.

In conclusion, by integrating cutting-edge observational datasets, state-of-the-art Earth system modeling, and sophisticated dynamical analyses, this research unravels the intricate mesoscale mechanisms underpinning Southern Ocean warming. It highlights the synergistic coupling of ocean physics, climate forcing, and energy conversions that together sculpt the spatial patterns of warming at high latitudes. This paradigm shift fosters optimism in our capacity to predict and, ultimately, mitigate the impacts of climate change on Earth’s most sensitive ocean frontiers.

Subject of Research: High-latitude warming hotspot in the Southern Ocean driven by ocean mesoscale eddies and their role in heat transport and energy conversion.

Article Title: High-latitude Southern Ocean warming hotspot induced by ocean mesoscale eddies.

Article References:
Li, D., Jing, Z., Cai, W. et al. High-latitude Southern Ocean warming hotspot induced by ocean mesoscale eddies. Nat. Clim. Chang. (2026). https://doi.org/10.1038/s41558-026-02652-7

DOI: https://doi.org/10.1038/s41558-026-02652-7

Image Credits: AI Generated

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Another fusion startup has raised another a massive round to make this type of power a reality.

Emerging scientific research reveals complex and regionally varied shifts in hailstorm hazards driven by global climate change, posing intricate challenges particularly for agricultural sectors. A recent comprehensive study by Raupach et al. (2026), published in Nature Climate Change, delves into the environmental drivers of hail-prone conditions worldwide, employing multiple atmospheric proxies combined with state-of-the-art climate model projections. Their findings paint a nuanced and sometimes contradictory picture of how hail frequency and intensity might evolve under warming scenarios, emphasizing both the uncertainty inherent in these projections and the profound implications for global food security.

Central to this study is the application of three distinct hail proxies — analytical tools that infer hail likelihood from large-scale atmospheric variables — across a wide ensemble of Coupled Model Intercomparison Project Phase 6 (CMIP6) climate model outputs. Each proxy incorporates different meteorological factors such as atmospheric instability, shear, melting-level height, and moisture content, leading to divergent projections especially in tropical regions. For instance, while the proxies developed by Raupach and SHIP integrate the moderating influences of low- to mid-tropospheric temperature and humidity and project decreases in hail-prone conditions in the tropics, the instability–shear proxy employed by Eccel predicts robust increases driven by heightened convective instability.

This disparity underscores a critical dynamic interaction within tropical atmospheres, where rising instability due to warming may be tempered by other thermodynamic factors such as increases in melting-level height and tropospheric moisture. The study details how the Raupach proxy, designed to factor in these complex interactions, demonstrates a muted sensitivity to instability in the tropics compared to mid-latitude environments, offering a plausible explanation for the contrasting responses. Notably, general tendencies of instability–shear proxies to overestimate tropical hail likelihood have previously motivated refinement efforts encapsulated in the Raupach model, highlighting ongoing challenges in accurately representing hail risk in diverse climatic zones.

Beyond regional discrepancies, the ensemble mean results project a broad poleward migration of hail-prone conditions as global mean temperatures increase by 2°C to 3°C. In mid-latitude regions such as the United States, Europe, and Australia, summer hail-prone day frequency is expected to decline or stabilize, counterbalanced by more subtle wintertime increases. These seasonal shifts reflect the juxtaposition of enhanced atmospheric instability promoting convective storm development against counteracting influences of elevated melting levels and moisture profiles. Crucially, this seasonal dichotomy suggests a differential impact on agronomic systems, with winter crops potentially facing augmented hail-related hazards, while summer crops could experience reduced risk exposure.

Methodologically, the integration of CMIP6 projections facilitates a comprehensive appraisal that incorporates changes in atmospheric circulation patterns alongside thermodynamic shifts—advancing beyond approaches relying solely on temperature and moisture trends. These results resonate with broader observed and projected trends, including the poleward displacement of storm tracks and the expansion of tropical latitudes. However, the study acknowledges generally low confidence in projecting dynamic aspects of severe convective storms, noting that variability in reanalysis datasets can sometimes exhibit opposite sign trends compared to model projections. This variability highlights the imperative to holistically quantify the relative roles of dynamic versus thermodynamic influences on hailstorm frequency and intensity.

Applying these hail hazard insights to agricultural risk, the study offers a preliminary exploration of potential crop vulnerability changes. Hailstorms rank among the most destructive extreme weather phenomena for crops, yet prior climate impact assessments have predominantly focused on gradual changes in temperature, precipitation, and CO₂ concentrations, often underrepresenting the relevance of episodic severe events. Although limited by stationary crop distribution datasets and the coarse spatial resolution of climate outputs, analyses suggest that poleward shifts in hail hazard could partly negate anticipated yield gains from climatic amelioration of growing conditions. This is especially salient for staple crops like maize cultivated in tropical regions where a projected decrease in hail frequency may somewhat buffer the negative effects of rising temperatures.

Further complicating the risk landscape are the myriad factors that govern actual crop damage from hail events. These include hailstone size, impact with coincident wind strength, and the timing of hailstorms relative to crop phenology. The study emphasizes the importance of considering shifting growing seasons and developmental milestones when assessing vulnerability, as these temporal factors can dramatically influence damage outcomes. Future studies incorporating dynamic agronomic modeling and phenological data are critical to refining risk assessments and guiding adaptive agricultural practices under a changing climate.

Intriguingly, while this investigation centers on hail-prone day frequency, it acknowledges emerging evidence that the severity and hailstone size may not track simply with frequency trends. Increasing atmospheric instability and moisture availability could enable growth of larger hailstones that survive melting layers, potentially offsetting declines in hail occurrence. Studies in the United States and Australia forecast such trends, with seasonal shifts favoring larger hailstones in the colder seasons, which could have disproportionate impacts on crops during critical stages of their growth cycles. These compounded risks necessitate enhanced atmospheric monitoring and more sophisticated proxy development capable of resolving changes in hailstone size distribution and intensity.

Global variability in hailstorm properties further complicates the extrapolation of proxies developed in one geographical context to others. Raupach et al. highlight the effort to design proxies that incorporate spatial heterogeneity in storm environments, validated across diverse regions such as the Australian continent. Nonetheless, the assumption of proxy stationarity—that the relationships between atmospheric variables and hail occurrence remain constant under future climates—introduces additional uncertainty. This uncertainty is exacerbated by differential hailstorm characteristics observed between land and maritime environments, where maritime hailstorm traits remain poorly understood and are excluded from this analysis focused on terrestrial projections.

The research also aligns hail hazard evolution with broader climatic phenomena such as the expansion of the tropics and poleward shifts in atmospheric storm tracks. These large-scale circulation changes modulate the frequency and intensity of convective storms, superimposed on thermodynamic trends from a warming planet. The study highlights the need for future work that disentangles these dynamic and thermodynamic components to better grasp their individual and interactive effects on hail risk. Such insights have vital implications not only for weather prediction but also for long-term climate adaptation strategies.

In integrating climatology with agriculture, this study signals the importance of reconsidering how extreme weather risks such as hailstorms are incorporated into assessments of global food security under climate change. Current crop impact models predominantly emphasize gradual climatic shifts, often missing the punctuated but devastating influence of hail. As cropping zones potentially migrate poleward with warming, hail risk may produce an attenuating effect on productivity gains. This complex interplay between hazard evolution and crop suitability underscores the necessity for interdisciplinary research spanning atmospheric science, agronomy, and risk management to safeguard future food supplies.

Moreover, the study addresses the limitations of current proxy-based analyses, recognizing that direct modeling of hailstorm severity and hailstone size from coarse-scale climate data remains elusive. The interplay of instability, moisture, temperature profiles, and dynamic atmospheric factors yields complicated, regionally nuanced responses difficult to resolve without higher-resolution data and improved parameterizations. The possibility that reductions in total hail frequency could coincide with increases in the occurrence of large, destructive hailstones is particularly concerning for winter-season crops, which may encounter intensifying risks that have not yet been fully characterized.

Finally, the authors prompt further investigation into the spatiotemporal dynamics of hail risk in a warming world. The complexity of the interactions, the heterogeneity of environmental proxies, and the variable sensitivity of different crops and cropping calendars together demand advanced modeling frameworks. Such frameworks should incorporate evolving atmospheric dynamics, soil-plant interactions, phenological shifts, and socio-economic factors governing adaptation capacity. As global warming continues to reshape the climate system, the multifaceted challenge of hail hazard evolution emerges as both a pressing scientific frontier and a critical societal concern.

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Subject of Research:
The study investigates the projected global changes in hailstorm hazard under climate warming and their implications for hail-related crop risk, analyzing atmospheric proxies and CMIP6 climate model scenarios.

Article Title:
Shifting hail hazard under global warming and effects on crop hail risk

Article References:
Raupach, T.H., Portmann, R., Siderius, C. et al. Shifting hail hazard under global warming and effects on crop hail risk. Nat. Clim. Chang. (2026). https://doi.org/10.1038/s41558-026-02660-7

Image Credits:
AI Generated

DOI:
https://doi.org/10.1038/s41558-026-02660-7

A groundbreaking new study has revealed an alarming intensification in the flashiness of river hydrographs worldwide, marking a significant shift in the behavior of earth’s freshwater systems under the influence of climate change. Published in Communications Earth & Environment, this research highlights not only the widespread nature of these changes but also their profound implications for water resource management, ecosystem stability, and hazard mitigation in coming decades. The findings serve as a stark reminder that climate dynamics are increasingly rewriting the hydrological patterns that humanity and nature rely on.

River hydrograph flashiness refers to the rapidity and magnitude of fluctuations in river discharge over short time scales. Traditionally, rivers exhibit relatively smooth changes in flow according to seasonal precipitation patterns and snowmelt. However, flashiness represents a scenario in which river discharge exhibits abrupt, intense peaks and troughs, shifting the timing and intensity of water availability. Such variability challenges downstream water infrastructure, destabilizes aquatic habitats, and exacerbates flood risks—a phenomenon that has now been identified as becoming pervasive on a global scale.

This comprehensive investigation leveraged a vast array of hydrological data spanning decades, integrating river gauge readings from thousands of sites across diverse climatic regions. By applying advanced statistical analyses to quantify flashiness indices, the researchers identified trends that point unmistakably towards enhanced flow variability coinciding with rising global temperatures and altered precipitation regimes. Importantly, the study confirms that this is not a localized problem: from arctic tundras to tropical basins, rivers are exhibiting increasingly erratic discharge patterns.

Climate change alters key drivers of hydrological cycles, including temperature, precipitation intensity, and snowpack dynamics. These changes translate into modified runoff regimes, as rainfall patterns become more intermittent yet intense, and melting glaciers contribute to erratic seasonal flows. The cumulative effect is a reshaping of river hydrographs towards heightened extremities — sudden spikes associated with storms followed by rapid declines, rather than prolonged periods of steady flow. This increased hydrograph flashiness signals a fundamental shift in river system behavior, complicating predictability and management efforts.

One of the critical implications of heightened river flashiness is its impact on flood frequency and magnitude. Sudden surges in river discharge, often triggered by extreme precipitation events, increase the likelihood of flash floods, which can destroy infrastructure, disrupt communities, and lead to loss of life. Simultaneously, rapid declines in flow during dry periods compromise water availability for agriculture, drinking, and industrial uses. This dual stress challenges traditional water management paradigms that rely on historical flow predictability, necessitating a reevaluation of policies and engineering designs.

Beyond human concerns, riverine ecosystems face significant threats due to changing flow variability. Many aquatic species have evolved life cycles synchronized with predictable flow patterns. The abrupt fluctuations associated with increased flashiness can disorient migratory fish, disrupt spawning, and degrade habitat quality by altering sediment transport and nutrient distribution. Moreover, riparian vegetation subjected to irregular inundation regimes may experience increased stress or mortality, destabilizing the entire river corridor ecology.

The study’s findings underscore the importance of integrating hydrograph flashiness metrics into climate impact assessments and water resource planning. Traditional hydrological models, which often emphasize mean flow or total annual runoff, may underestimate risks posed by extreme variability. Updating predictive frameworks to incorporate flashiness will improve hazard forecasting, guide infrastructure resilience measures, and support adaptive management strategies that can cope with more volatile hydrological realities.

Researchers employed novel remote sensing technologies alongside ground-based river gauges to capture high-resolution temporal data, enabling more precise detection of flashiness trends than previously possible. Coupled with machine learning algorithms for pattern recognition, these methodologies allowed for robust global comparisons, illustrating that intensified hydrograph flashiness is a systemic consequence of anthropogenic climate change rather than isolated anomalies attributable to local land use or hydrological modifications.

The study also explored regional disparities in flashiness intensification. For example, mountainous basins influenced by glacial retreat exhibit pronounced seasonal variability, while tropical monsoon regions encounter intensified storm-driven discharge peaks. Arid and semi-arid zones, already vulnerable due to scarce water resources, face exacerbated risks from flashiness that may jeopardize water security further. Such regional nuances highlight the necessity for tailored adaptation approaches reflecting localized hydrological contexts.

Mitigation strategies proposed in response to these findings focus on enhancing river basin resilience through integrated water resource management. This involves optimizing reservoir operation schedules to buffer against sudden inflows, restoring wetlands that naturally attenuate flood peaks, and adopting green infrastructure solutions to promote groundwater recharge during erratic precipitation. Coordinated international efforts will be vital for transboundary rivers that traverse multiple national jurisdictions.

Public awareness and policy engagement are equally crucial in addressing the challenges posed by intensifying river flashiness. Governments and stakeholders must be informed about these emerging risks to prioritize investments in infrastructure upgrade, early warning systems, and community preparedness. Enhanced educational outreach can galvanize support for sustainable land use practices that reduce runoff velocity and inert urban flooding dynamics, thereby mitigating some of the human-induced exacerbation of flashiness.

Furthermore, ongoing monitoring and research are essential to refine understanding as climate change continues to evolve. The dynamic nature of hydrographic responses calls for continuous data acquisition to detect emerging patterns, evaluate intervention efficacy, and update predictive models accordingly. International collaborations and open data sharing will accelerate knowledge dissemination and foster innovative solutions to cope with these new hydrological realities.

In conclusion, the widespread intensification of global river hydrograph flashiness reflects a profound hydrological transformation prompted by climate change. This phenomenon introduces heightened uncertainties and risks that permeate ecological integrity, human livelihoods, and infrastructure stability. Recognizing and responding to these shifts with informed scientific insights, adaptive management, and proactive policy measures is imperative to safeguard water resources and ecosystem services in an increasingly unpredictable world. The research stands as both a warning and a call to action for the global community to address the cascading consequences of a warming planet on its vital freshwater systems.

Subject of Research: Global intensification of river hydrograph flashiness under climate change and its hydrological, ecological, and societal impacts.

Article Title: Widespread intensification of global river hydrograph flashiness under climate change.

Article References:

Zhu, S., Li, Z., Yan, S. et al. Widespread intensification of global river hydrograph flashiness under climate change.
Commun Earth Environ (2026). https://doi.org/10.1038/s43247-026-03681-y

Image Credits: AI Generated

DOI: 10.1038/s43247-026-03681-y

Keywords: river hydrograph flashiness, climate change, extreme hydrological events, flood risk, water resource management, hydrology, ecosystem impacts, global warming

In December, the Trump administration abruptly announced it would shut down the National Center for Atmospheric Research (NCAR), a Boulder, Colorado-based facility that helps researchers perform studies of weather, climate, atmospheric chemistry, and more. The news came as a shock, given that the government had never identified serious deficiencies in the management of NCAR and its associated supercomputing center in Wyoming.

Nevertheless, the government ordered the University Consortium for Atmospheric Research (UCAR), which manages NCAR on behalf of the National Science Foundation, to help it prepare to transfer the Wyoming facility to a different operator. UCAR sued the government and, on Monday, won a preliminary injunction that places the transfer of the facility on hold.

Is that your final decision?

NCAR is what is termed a "Federally-Funded Research and Development Center" meant to support researchers in the academic community. Rather than having its own research agenda, it provides facilities, equipment, and expertise to support projects that are too large or complex for researchers to pursue on their own. NCAR has been around since the early 1960s and has become a critical resource for the global atmospheric science community.

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© Matthew Jonas/MediaNews Group/Boulder Daily Camera via Getty Images

In December, the Trump administration abruptly announced it would shut down the National Center for Atmospheric Research (NCAR), a Boulder, Colorado-based facility that helps researchers perform studies of weather, climate, atmospheric chemistry, and more. The news came as a shock, given that the government had never identified serious deficiencies in the management of NCAR and its associated supercomputing center in Wyoming.

Nevertheless, the government ordered the University Consortium for Atmospheric Research (UCAR), which manages NCAR on behalf of the National Science Foundation, to help it prepare to transfer the Wyoming to a different operator. UCAR sued the government and, on Monday, won a preliminary injunction that places the transfer of the facility on hold.

Is that your final decision?

NCAR is what is termed a "Federally-Funded Research and Development Center" meant to support researchers in the academic community. Rather than having its own research agenda, it provides facilities, equipment, and expertise to support projects that are too large or complex for researchers to pursue on their own. NCAR has been around since the early 1960s and has become a critical resource for the global atmospheric science community.

Read full article

Comments

© Matthew Jonas/MediaNews Group/Boulder Daily Camera via Getty Images

In December, the Trump administration abruptly announced it would shut down the National Center for Atmospheric Research (NCAR), a Boulder, Colorado-based facility that helps researchers perform studies of weather, climate, atmospheric chemistry, and more. The news came as a shock, given that the government had never identified serious deficiencies in the management of NCAR and its associated supercomputing center in Wyoming.

Nevertheless, the government ordered the University Consortium for Atmospheric Research (UCAR), which manages NCAR on behalf of the National Science Foundation, to help it prepare to transfer the Wyoming facility to a different operator. UCAR sued the government and, on Monday, won a preliminary injunction that places the transfer of the facility on hold.

Is that your final decision?

NCAR is what is termed a "Federally-Funded Research and Development Center" meant to support researchers in the academic community. Rather than having its own research agenda, it provides facilities, equipment, and expertise to support projects that are too large or complex for researchers to pursue on their own. NCAR has been around since the early 1960s and has become a critical resource for the global atmospheric science community.

Read full article

Comments

© Matthew Jonas/MediaNews Group/Boulder Daily Camera via Getty Images

In December, the Trump administration abruptly announced it would shut down the National Center for Atmospheric Research (NCAR), a Boulder, Colorado-based facility that helps researchers perform studies of weather, climate, atmospheric chemistry, and more. The news came as a shock, given that the government had never identified serious deficiencies in the management of NCAR and its associated supercomputing center in Wyoming.

Nevertheless, the government ordered the University Consortium for Atmospheric Research (UCAR), which manages NCAR on behalf of the National Science Foundation, to help it prepare to transfer the Wyoming facility to a different operator. UCAR sued the government and, on Monday, won a preliminary injunction that places the transfer of the facility on hold.

Is that your final decision?

NCAR is what is termed a "Federally-Funded Research and Development Center" meant to support researchers in the academic community. Rather than having its own research agenda, it provides facilities, equipment, and expertise to support projects that are too large or complex for researchers to pursue on their own. NCAR has been around since the early 1960s and has become a critical resource for the global atmospheric science community.

Read full article

Comments

© Matthew Jonas/MediaNews Group/Boulder Daily Camera via Getty Images

Antarctica has been impacted by three major events, which researchers have identified as a “perfect storm” that could finally initiate major melting on the icy continent, with major implications for exacerbating climate change.

According to new University of Southampton research, these events have begun a spiral that could move the global oceans from a hedge against climate change, to one of its primary drivers.

In a recent paper published in Science Advances, the team behind the study used satellite data to identify the root causes of record-low sea ice in the Antarctic and the potential future effects on the global climate.

The Resilient Antarctic

While other parts of the world have been feeling the effects of global climate change for some time, it was only about a decade ago, in 2015, that Antarctic sea levels stopped rising and began retreating. The reason for this sudden reversal perplexed scientists until the University of Southampton team finally identified a series of Southern Ocean events that snowballed into a major climate concern, as they pulled up warm, salty water from below the surface.

By 2023, this chain of events had destroyed enough ice to cover Greenland, pushing the lows ever further.

“Antarctic sea ice in the Southern Ocean helps drive the planet’s ocean overturning circulation,” said lead author Dr. Aditya Narayanan, an oceanographer from the University of Southampton. “However, since 2015, the region has undergone a huge transformation, with extreme ice loss around the continent.”

“What started as a slow build-up of deep-sea heat under the Antarctic sea ice was followed by a violent mixing of water, ending in a vicious cycle where it’s too warm to let ice recover,” Dr. Narayanan says. “It’s concerning because massive loss of sea ice destabilizes the world’s ocean current systems, warming our planet far quicker than expected.”

Observing a Climate Crisis

The team used an advanced ice-measuring program that combined two approaches to identify three specific events responsible for the cascading ice loss. 

“We use a combination of satellite observations and computer models — both of which are part of long-running international efforts,” Dr. Narayanan told The Debrief in an email. “The satellite data come from the National Snow and Ice Data Center (NSIDC), which compiles and distributes global sea ice records.”

“These measurements rely on instruments such as the Advanced Microwave Scanning Radiometer 2 (AMSR2), operated by the Japan Aerospace Exploration Agency (JAXA),” Dr. Narayanan added. “These sensors can ‘see’ through clouds and darkness, allowing us to track sea ice year-round.”

The Southampton team then ran this data through the Southern Ocean State Estimate, an advanced computer model created at the Scripps Institution of Oceanography.

“This is not just a standalone simulation—it combines the laws of physics with real-world observations, such as temperature, salinity, and sea ice data,” Dr. Narayanan said. You can think of it as a model that is constantly guided by observations, so it stays close to what is actually happening in the ocean.”

‘Three Horsemen’ of the Antarctic

The issues began around 2013, when strong winds raised Circumpolar Deep Water, a warm, salty solution from the deep. Then, in 2015, stronger winds mixed that water directly into the surface layer, producing the rapid ice loss observed at the time, concentrated in the east. By 2018, surface water had reached a threshold at which so much warm, salty water had surfaced that ice formation became difficult, reinforcing the cycle.

The team discovered that this oceanic ice loss is primarily occurring in the East Antarctic, where the deepwater upsurge is primarily occurring. The West is not in the clear, though, as intense cloud cover over the subtropics has now heated the ocean, leading to major ice melt between 2016 and 2019.

“More recent observations, including near-real-time data from the National Snow and Ice Data Center(NSIDC), show that parts of West Antarctica, especially near the Antarctic Peninsula, are again experiencing low sea ice in certain seasons,” Dr. Narayanan told The Debrief. “Without carrying out a specific study, it is difficult to pinpoint a single cause for these recent changes.”

“Most likely, they reflect a combination of atmospheric conditions, such as clouds and winds, and heat being delivered by the ocean,” Narayanan said.

The Future of the Antarctic Climate

“This isn’t just a regional problem, Antarctic sea ice acts as Earth’s mirror, reflecting solar radiation back into space,” said co-author Dr. Alessandro Silvano, also from the University of Southampton. “Its loss could destabilize the currents that store heat and carbon in the ocean, accelerating global warming, and also destabilize ice shelves that prevent glaciers from sliding into the sea, raising global sea levels.”

The researchers warn that anthropogenic climate change is fueling the warm winds driving these events in the Antarctic. 

“Were these trends to persist, the planet could experience a ‘prolonged low sea-ice state,’” said co-author Professor Alberto Naveira Garabato from the University of Southampton.

“If the low sea-ice coverage prevails into 2030 and beyond, the ocean may transition from a stabilizer of the world’s climate to a powerful new driver of global warming,” Garabato added.

The paper, “Compound Drivers of Antarctic Sea Ice Loss and Southern Ocean Destratification,” appeared in Science Advances on May 8, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.

The South Pacific blast may have consumed its own methane — but using this idea against the greenhouse gas is controversial.

A global model suggests that climate change could make hailstones larger and more damaging in many regions, especially at mid-to-high latitudes.

Most people think of Mars as a big red dustball, but researchers recently found Martian mineral deposits suggesting it was once warm and humid. The team used the Compact Reconnaissance Imaging Spectrometer aboard NASA’s Mars Reconnaissance Orbiter to analyze specific wavelengths of visible and near-infrared light from minerals on Mars’s surface to determine their chemical composition from afar.

Past researchers identified layered silicate minerals, called clays, across the Martian surface. Clays form when water interacts with rock, and record the amounts and chemical compositions of the waters that formed them. As water interacted with Martian surface rocks, it picked up more mobile elements like magnesium and iron and carried them to lower depths in the Martian soils, while less mobile elements like aluminum stayed in place. This process, called leaching, created 2 distinct layers of clays in the Martian rocks. 

Scientists have proposed 2 main hypotheses for how these layered clays formed on Mars. The first is that they formed through underwater leaching in pools or lakes sometime in Mars’ past. The second is that they formed across the Martian surface, where a widespread humid environment provided the moisture needed to leach them. 

To evaluate these hypotheses, a team led by researchers at Purdue University recently estimated the “true” thicknesses of Martian clay layers with a method scientists had previously only used on Earth. Rock layers containing clays can become tilted, making them appear thicker or thinner than they actually are. To address this discrepancy, the team used the High Resolution Imaging Science Experiment (HiRISE) tool on the Mars Reconnaissance Orbiter to create high-resolution elevation maps of the Martian surface. Then they combined these maps with surface composition data from the Compact Reconnaissance Imaging Spectrometer to create 3D composition maps. 

Using the 3D composition maps, the researchers found where each clay layer was exposed at the surface and traced it underground to estimate an angle of tilt. They then used trigonometry to calculate the true thicknesses of each clay layer. They analysed 46 regions across the Martian surface, and found that the combined thickness of both clay layers was around 20 to 680 feet (6 to 200 meters), with an average of about 190 feet (60 meters). That’s a maximum thickness as high as a 60-story building! 

Next, the researchers tested the extent of the clay deposits in a large ancient Martian valley known as the Mawrth Vallis Region. They focused on this region because it had large elevation changes, and scientists in the past had already collected high-resolution chemical composition and elevation data there. 

They explained that if the clay layers were restricted to the lowest parts of the valley where water once existed, and had changing thicknesses and boundaries between layers, this would provide strong evidence in favor of the “underwater leaching” hypothesis. In contrast, if the clay layers were more widespread, with consistent layer boundaries and thicknesses, this would provide strong evidence of a humid surface environment, in favor of the “surface leaching” hypothesis. 

The researchers found that the clay layers extended beyond the lowest parts of the valley and had consistent layer boundaries across more than half a mile (about a kilometer) of elevation change. Thus, they concluded that the clay layers formed by surface leaching in a humid environment. 

These findings conflict with climate models of early Mars, which generally suggest that the Martian surface rarely got above freezing temperatures. To address this discrepancy, the team proposed that these deposits could have formed over a long period of time rather than in a consistently warm and wet environment. If the surface was frozen most of the time, but got above freezing in short bursts, these clay deposits could still have formed, just over a much longer time period. In this case, the Mars climate models and the researchers’ findings would agree.

The researchers acknowledged that their study has some limitations, particularly regarding the sparse sample locations. Though they found strong evidence for a widespread humid environment on early Mars, more in-depth studies of locations like Mawrth Vallis could better constrain the specific surface environmental conditions under which these clays formed and potentially reconcile their data with Martian climate models.

The post Clay minerals suggest a warm, wet past for Mars appeared first on Sciworthy.

The years 2023 and 2024 were the warmest on record, coinciding with a powerful Pacific climate event known as El Niño. El Niño is the warm phase of a natural climate cycle in which surface waters in the eastern Pacific are unusually warm, bringing record-breaking heatwaves in the Amazon and heavy rainfall in the southern USA. Its counterpart, La Niña, is the cool phase that brings wetter conditions to the Northern USA. 

In a typical El Niño, warm water in the eastern Pacific weakens the winds blowing westward across the tropical Pacific, known as trade winds, allowing more warm water to flow eastward – a self-reinforcing cycle that amplifies the event. However, the 2023 El Niño differed because the ocean warmed intensely, but the trade winds remained strong. Researchers from the Scripps Institution of Oceanography, led by Qihua Peng and Shang-Ping Xie, recently investigated how and why this unusual event occurred.

First, the researchers tracked how air pressures changed across the Pacific during the event using a metric calculated by NOAA, known as the Southern Oscillation Index. When the eastern Pacific warms during an El Niño, the difference in air pressure across the Pacific typically decreases. In 2023, they found that temperatures in the eastern Pacific rose to more than 3°F (2°C) above normal, yet the drop in air pressure was only about 31% as strong as they expected. They also calculated that changes in wind speed and direction could only account for about 30% of the warming. So why was the 2023 El Niño so strong?

To answer this question, the research team then looked beyond the Pacific, analyzing sea surface temperatures from NOAA satellite data. They found that the North Atlantic and Indian Oceans also experienced record-breaking heat in 2023, with temperatures in the North Atlantic exceeding 2°F (1°C) above normal – the warmest in recent history. This suggested that El Niño events can develop in response to ocean conditions worldwide, not just those in the Pacific.

Next, the team used a computer program that simulates how the atmosphere responds to ocean temperatures, called the Community Atmosphere Model, to examine how heat from other oceans affects the Pacific. They found that heat in the North Atlantic and Indian Oceans generated large columns of hot air rising over those regions. This air cooled at high altitudes and then sank over the central Pacific, strengthening a large-scale loop of rising and sinking air that drives trade winds westward. Strengthening this circulation worked against El Niño by keeping trade winds blowing westward about 30% more strongly than Pacific warming alone would have. If the trade winds remained strong, why was the eastern Pacific so warm in 2023?  

To answer this question, the researchers studied 3 consecutive La Niña years between 2020 and 2023, analyzing ocean temperature and sea level data from NOAA’s Global Ocean Data System. During those years, strengthened trade winds transported heat into the western Pacific. As the seawater got warmer, it expanded, a process known as thermal expansion. Over those 3 years, thermal expansion and constant wind created a “pile” of warm water in the western Pacific, which reached its highest level of stored heat since 1982. When the trade winds eventually relaxed as La Niña faded, this piled-up warm water surged eastward, setting the stage for the El Niño event.

To test whether this stored heat alone could drive an El Niño, the team used a computer program that models oceanic and atmospheric interactions, called a coupled general circulation model. They input observed ocean temperatures from April 1, 2023, when La Niña ended, but removed all wind changes after that date. Their model successfully reproduced 87% of the warming observed between June and December 2023, which suggested that trade winds contributed just 13%. Stored heat was carried eastward by massive underwater waves traveling along the equator. As these waves reached the Eastern Pacific, they pushed cold water deeper, allowing surface water to warm. The researchers concluded that this oceanic process drove the 2023 El Niño to develop without the usual wind-driven feedback.

The team suggested that in a warming world, large heat reservoirs in the western Pacific will likely become more common, leading to more frequent strong El Niños. However, because their analysis focused on a single event, it remains unclear how often El Niños develop through oceanic processes alone. Ultimately, their study showed that the ocean can be more than a passive partner in El Niño – it can be the driving force.

The post Why the 2023 El Niño broke records appeared first on Sciworthy.

A new Australian initiative is sending Year 9-12 students to one of the most extreme scientific environments on Earth, and asking them to contribute to real research while they’re there. For most students,...

The post Antarctica: The ultimate classroom first appeared on Science Illustrated.

The amount of moisture in soil – and the way this moisture is distributed – combined with wind patterns in the lowest few kilometres of the atmosphere can influence where thunderstorms begin and how they develop. This new finding, from researchers at the UK Centre for Ecology and Hydrology (UKCEH) could help in the development of new early warning systems for such events, which are increasing worldwide and becoming more intense and dangerous as the climate warms.

Thunderstorms can develop quickly on hot afternoons, sometimes in less than half an hour of clouds building up, but predicting where they originate can be difficult.

A team of researchers led by meteorologist Christopher Taylor has now discovered that patches of dry soil 10–50 km across can combine with the wind field and affect how quickly convective storm clouds (cumulonimbus) form and grow.

“We already knew that differences in wind speed and direction with height (the ‘vertical wind shear’) in the atmosphere are critical ingredients for severe storm development, whilst gradients in land surface heating across the landscape can induce weak winds near the ground,” explains Taylor. “These two elements are usually studied separately, but we put them together and found that convective clouds grow very rapidly when the winds that steer them, some 3–4 km above the ground, oppose local surface-generated winds near the ground.”

This combination, he says, effectively increases the supply of moist, buoyant air into a cloud, accelerating the updraughts responsible for lightning and heavy rain.

“Storm initiations are clearly favoured in specific locations”

The result, he explains, challenges conventional thinking that over flat terrain, where cumulonimbus first develop, is essentially random. “In fact, under the conditions we studied – across sub-Saharan Africa – storm initiations are clearly favoured in specific locations, based on a combination of soil and wind conditions on that day.”

The work, which is detailed in Nature, could help in the development of more localized storm forecasting, he says, particularly in tropical areas where soil moisture gradients and wind shear are strong and can lead to flash flooding, lightning and strong winds.

The UKCEH team obtained its result by studying satellite images of 2.2 million afternoon storms in 2004–2024. They were able to obtain high-resolution data from the images and so observe fine-scale details of the wetness of soils.

The principle they have identified would be applicable to predicting thunderstorm formation in other parts of the world, such as Asia, the Americas, Australia and Europe – and not just the worst-hit tropical regions in Africa.

Ground-based measurement networks are scarce in Africa

Taylor and colleagues say they have been working with meteorological services in Africa for the last few years and contributing to international efforts to provide early warning systems for severe storms. Convective storms can be particularly damaging in built-up urban areas with intense rainfall damaging infrastructures such as roads and sanitation systems. “Unlike in the UK, where ground-based measurement networks are the backbone of weather forecasting, they are scarce in Africa and there are only a handful of meteorological radars here, explains Taylor. “We therefore had to rely on satellite data, which provide good quality information on some aspects of the coupled land-atmosphere system – notably the temperature (and therefore the height) of clouds and estimates of moisture in the top few centimetres of the soil.”

From this information, the researchers inferred how soil moisture affects evapotranspiration and atmospheric heating, how pressure gradients created by these heating patterns affect winds locally and, finally, how these inferred local winds interact with growing convective clouds.

The insights gleaned from this study could help improve the accuracy of short-term weather forecasts by providing a better indication of where storms are likely to appear within a region, Taylor says. “Just how much more skilful a forecast will be is an open question, but we have good reason to believe that in parts of Africa it could provide a big advance. In general, weather forecasting is a rapidly evolving field thanks to AI, and so the translation from research finding to application could be rapid.”

The researchers say they are now starting to look at how weather forecast models depict the processes described in their work. “Early indications suggest that models solving physical equations on a fine enough grid (of around 4 km) can capture the relationships between soil moisture, wind shear and cloud growth, but operational weather forecast models will require more accurate information on spatial variations of soil moisture to produce better forecasts,” says Taylor.

“We are also looking at how predictive models based on deep learning can exploit the new knowledge to provide forecasters with early indications of where storms may appear later in the day,” he reveals.

The post Where do thunderstorms form? appeared first on Physics World.

Wake-up call, and a call to arms The spectacular feature-length documentary ‘Ocean with David Attenborough’ is his very first partnership with National Geographic, now showing on Disney+ channel in Australia. With the great...

The post ‘Ocean with David Attenborough’ – masterpiece and call to action first appeared on Science Illustrated.