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Techniques to reflect an additional small portion of sunlight back into space could help cool the planet if deployed globally, but they cannot address the full range of climate impacts or replace emission cuts, according to a Royal Society briefing.

We've gone to the bottom of the ocean to study how its chemistry shapes our planet's climate, even chasing lava-spewing underwater volcanoes to do it. But it turns out we may have missed something far closer to home: the water beneath our feet.

A study published in Nature Climate Change by an international team of scientists from the IBS Center for Climate Physics (ICCP) at Pusan National University in South Korea, presents new evidence that ocean turbulence and a process known as "horizontal stirring" will increase dramatically in the Arctic and Southern Oceans due to human-induced global warming and decreasing sea ice coverage.

Beneath the surface of lakes and coastal waters lies a hidden world of sediment that plays a crucial role in the health of aquatic ecosystems. "Benthic fluxes" of nitrogen and phosphorus, such as releases of these dissolved nutrients from sediments to their overlying waters, can fuel algae growth and toxic harmful algal blooms (HABs), which degrade water quality, disrupt wildlife and recreation, and reduce property values.

When we look at the towering trees of old-growth forest patches in the Amazon, we might think these ancient beings have reached their maximum size and width.

It turns out they have not, a new study suggests. It shows that even the largest and oldest Amazonian trees still capture carbon dioxide (CO2)—and keep getting bigger, albeit at a slow pace.

Led by Adriane Esquivel-Muelbert, an ecologist at the University of Cambridge, the researchers analyzed 3 decades of tree measurements from 188 primary forest plots spread across nine Amazonian countries. Each plot was around 1 hectare, about the size of a city block, and was measured by teams using tapes and notebooks, often under harsh conditions.

The plots were selected from the Amazon Forest Inventory Network (RAINFOR), which has become one of the most important monitoring efforts in tropical ecology, according to Esquivel-Muelbert. The monitoring period varied between 1971 and 2015.

“We already knew the Amazon works as a carbon sink,” she said. “But we wanted to understand what’s happening inside the forest—what kinds of trees are changing, and how.”

The study, published in Nature Plants, found that the average tree size had increased by 3.3% per decade over the past 30 years. Large-canopy trees—those with trunks wider than 40 centimeters—grew even faster in diameter. Smaller trees shaded by larger ones also grew, while the size of medium-sized trees remained relatively stable.

The consistency across the Amazon basin suggests the increasing amount of CO2 in the atmosphere is the ingredient fattening up the trees. “Carbon is an extra resource,” Esquivel-Muelbert explained. “With the same amount of light, a plant can photosynthesize more efficiently when there’s more CO2 available.”

In other words, as humans release more carbon into the atmosphere, Amazonian trees seem to be using some of it to grow. The researchers interpreted the pattern as a mix of two effects: a winner-takes-all response, in which the tallest trees gain even more advantage, and a carbon-limited benefit response, in which smaller, shaded trees find it easier to survive in low light. Both effects can occur at the same time, leading to more biomass for both groups at the extremes of the size scale.

The study also found no sign that large trees are dying faster, contradicting earlier hypotheses that canopy giants would be the first casualties of heat and drought. The resilience of these ancient trees—some of them centuries old—is important because they sequester a disproportionate share of the forest’s carbon.

“The largest 1% of trees account for about half of all the carbon stored and absorbed by the forest,” Esquivel-Muelbert said. Losing them would mean losing much of the Amazon’s buffering power against climate change.

Not Exactly Good News

“It doesn’t mean carbon dioxide is good for the forest. What we’re seeing is resilience, not relief.”

The findings might sound like good news, but “it doesn’t mean carbon dioxide is good for the forest,” Esquivel-Muelbert said. “What we’re seeing is resilience, not relief.”

Carbon dioxide might be fattening up old trees, but its consequences for the global climate totally offset what might look like an advantage or a good thing at first sight, she emphasized.

To Tomás Domingues, a forest ecologist at the Universidade de São Paulo in Ribeirão Preto, the new results offer valuable real-world confirmation of what experimental models have long proposed. “The study shows that the community as a whole is gaining biomass, presumably due to higher CO2,” he said. “That aligns perfectly with what we’re testing at AmazonFACE.”

AmazonFACE—a large-scale open-air experiment near Manaus in the Brazilian state of Amazonas—exposes forest patches to elevated concentrations of atmospheric carbon to simulate future conditions. One of its main goals is to see how long the carbon fertilization effect can last before the forest runs into another limitation: the lack of nutrients such as phosphorus, calcium, magnesium, and potassium.

“The CO2 effect has a short life,” Domingues explained. “Trees can only turn extra carbon into growth if they have enough nutrients. In the Amazon, everybody—trees, microbes, fungi, insects—is competing for the same scarce resources.” If nutrients become limited, he added, growth could plateau or even reverse, regardless of the CO2 supply.

Still Holding On

The new findings highlight how complex the Amazon’s responses to human-driven change can be. While extra carbon has acted as a growth stimulus so far, climate stressors, especially heat, drought, and windstorms, are also intensifying.

Previous studies suggested that the Amazon’s overall carbon storage capacity is starting to weaken. Changes in species composition, repeated droughts, and the spread of degradation along the southern and eastern edges of the basin are already weakening parts of the system. “The forest is still resisting,” Esquivel-Muelbert said, “but that doesn’t mean it will resist forever.”

“These forests are resilient, but they’re irreplaceable. If we lose them, they don’t come back in our lifetime.”

Domingues noted that 30 years of observations, though impressive for tropical fieldwork, still capture only a short moment in ecological time. “For the forest, 30 years is nothing,” he said. “These trees live for centuries. We need to keep watching.”

Despite the unknowns, both researchers are clear: Protecting mature, intact forests is crucial if we want to fight climate change. Reforestation won’t replace the carbon storage capacity of old-growth trees. “These forests are resilient, but they’re irreplaceable,” Esquivel-Muelbert said. “If we lose them, they don’t come back in our lifetime.”

The study’s main message, Esquivel-Muelbert added, is not that the Amazon is thriving under climate change. It’s that the forest is still holding on, at least for now.

—Meghie Rodrigues (@meghier.bsky.social), Science Writer

Citation: Rodrigues, M. (2025), As CO2 levels rise, old Amazon trees are getting bigger, Eos, 106, https://doi.org/10.1029/2025EO250413. Published on 5 November 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

The outlook for our planet’s water future is anything but reassuring. Across much of the world, communities are already confronting prolonged drought, shrinking reservoirs, and the growing struggle to secure reliable access.

“Even without global warming, if water demand continues to rise steadily, scarcity is inevitable.”

Now, a new study in Nature Communications suggests that so-called day zero droughts (DZDs)—moments when water levels in reservoirs fall so low that water may no longer reach homes—could become common as early as this decade and the 2030s.

To find out where and when DZDs are most likely to occur, scientists at the Center for Climate Physics in Busan, South Korea, ran a series of large-scale climate simulations. They considered the imbalance between decreasing natural supply (such as years of below-average rainfall and depleted river flows) and increasing human demand (including surging economic and demographic growth).

“Most studies tend to focus on supply alone, not on the interplay between supply and demand,” explained Christian L. E. Franzke, a climate scientist and coauthor of the study. “But even without global warming, if water demand continues to rise steadily, scarcity is inevitable.”

Cities on the Edge of Thirst

The team found that urban areas face the highest risk of DZDs. As cities expand, their thirst for water often exceeds what local systems can provide, leaving them exposed to shortages and instability.

The near catastrophe in Cape Town in 2018, when water was rationed to avoid a complete shutdown, remains a stark warning for cities worldwide. “I remember the measures that had to be taken,” Franzke said. “There were severe restrictions—people had to limit their use to just a few liters a day.”

Central spatial maps (a) and (b) show the spatial distribution of the ensemble mean waiting time and duration of day zero drought (DZD) events, respectively, following the time of first emergence (TOFE) at each grid point of DZD-prone regions across the globe. Map (c) represents the spatial distribution of the frequency (%) of extreme DZD events, defined as those where the event duration exceeds the waiting time, indicating prolonged water scarcity impact and short recovery period. The accompanying inset circular diagram illustrates the distribution of these events, with the color scale indicating the proportion (percentages) of grid cells experiencing such conditions. The surrounding paired panels depict the probability density function (PDF) of waiting time and duration for DZD events across seven DZD-prone regions. The vertical dashed lines mark the ensemble mean (black), 90th percentile (blue), and 99th percentile (green) for each region. The red dashed line represents the monthly scale of the compound extreme event, which is 48 months. The period considered for each grid point starts from the month after each decade of their respective TOFEs and continues until 2100. Click image for larger version. Credit: Ravinandrasana and Franzke, 2025, https://doi.org/10.1038/s41467-025-63784-6, CC BY-NC-ND 4.0

The human toll of DZDs goes beyond empty taps. It deepens existing inequalities, hitting low-income communities hardest because they are generally less able to endure rising costs of accessing clean water while also being more reliant on public utilities that are slower to secure alternate water sources. Urban DZDs also threaten public health by disrupting sanitation.

Overall, a DZD weakens economies and undermines social stability—especially in developing regions where physical, economic, and institutional vulnerabilities overlap.

According to the study, regions along the Mediterranean, southern Africa, and parts of North America are likely hot spots for DZDs, places where the zero point could arrive much sooner and last much longer.

“These already dry regions are becoming even drier,” said Alejandro Jaramillo Moreno, a hydroclimatology specialist from the Department of Atmospheric Sciences at Universidad Nacional Autónoma de México. Jaramillo was not involved in the new study. “Global warming is amplifying the contrast between wet and dry areas. Where rainfall is scarce, it will likely become scarcer.”

Avoiding the Tipping Point

For Franzke, solutions must come not only from individuals using water more responsibly but also from policymakers who prioritize smart management and modern infrastructure. “There’s a lot of leakage,” he said. “Pipes are old, and water escapes before it reaches people. Updating this infrastructure is crucial.”

It may seem unthinkable that metropolises like Los Angeles could one day face evacuation because of water shortages, but experts warn that this scenario isn’t far-fetched if systemic solutions aren’t implemented.

In many regions, water rationing caused by severe drought is already a reality. Chile, for instance, has experienced a water crisis for more than a decade, and water is rationed in areas including the nation’s capital and largest city, Santiago. Iraq, Syria, and Turkey are experiencing one of the worst regional droughts in their modern histories.

Jaramillo takes a long view of civilizations’ relationship with water supply. “Throughout history, cities have reached their zero point—not only in water but in other essential resources,” he reflected. “The difference is that now, we still have time (and knowledge) to change course.”

—Mariana Mastache-Maldonado (@deerenoir.bsky.social), Science Writer

Citation: Mastache-Maldonado, M. (2025), Are “day zero droughts” closer than we think? Here’s what we know, Eos, 106, https://doi.org/10.1029/2025EO250409. Published on 5 November 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

The United States is falling far behind China in remote sensing research, according to a comprehensive new study that tracked seven decades of academic publishing and reveals a notable reversal in global technological standing.

Ancient trees may have played a key role in regulating Earth's climate during the last ice age—by 'breathing' less efficiently.

Earth is reflecting less sunlight, and absorbing more heat, than it did several decades ago. Global warming is advancing faster than climate models predicted, with observed temperatures exceeding projections in 2023 and 2024. These trends have scientists scrambling to understand why the atmosphere is letting more light in.

A Peking University research team led by Wang Heyuan and Wang Kai at the Institute for Carbon Neutrality (ICN) used AI models to determine that the global land carbon sink has drastically shrunk due to an abrupt and extreme jump in global temperature. Their study, "AI-tracked halving of global land carbon sink in 2024," was published in Science Bulletin.

A research team led by Professor Zhang Qinghong and Li Rumeng from the Department of Atmospheric and Oceanic Sciences at Peking University (PKU) School of Physics, has found that hailstorms in China have surged since the Industrial Revolution, likely due to human-driven climate warming. The study, published in Nature Communications in September 2025, combines historical records, meteorological data, and artificial intelligence to track long-term hailstorm trends.

Small mountain ponds high in the tropical Andes may be playing an outsized role in global climate change, according to new research led by scientists at the University of North Carolina.

Microorganisms in the Black Sea can produce large amounts of the potent greenhouse gas nitrous oxide (N2O). However, this gas never reaches the atmosphere because it is swiftly consumed by other microorganisms, which convert it to harmless dinitrogen gas (N2). Scientists from the Max Planck Institute for Marine Microbiology have now investigated this process and identified the key players involved.

With heat waves among Europe's deadliest climate hazards, a team of scientists led by CMCC has developed a prediction system capable of providing helpful information four to seven weeks before summer, which gives valuable time to improve preparedness.

In a new study published in Global Change Biology, Prof. Zhang Yuanming's team from the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences has unveiled a previously underestimated factor in greenhouse gas emissions from arid environments: hydroxyl radicals, often dubbed "free radicals."

body {background-color: #D2D1D5;} Research & Developments is a blog for brief updates that provide context for the flurry of news that impacts science and scientists today.

Current emissions trajectories look set to warm the world by as much as 2.8°C (5.04°F) above preindustrial levels by 2100, according to a report released today by the United Nations Environment Programme (UNEP).

While some progress has been made on global emissions cuts, much more ambitious changes are necessary to avoid the worst of climate change’s effects.

The UNEP Emissions Gap Report is an annual stocktake of the gap between countries’ emissions reduction plans and actions needed to keep Earth’s temperature below the 1.5°C (2.7°F) warming limit set by the Paris Agreement, a legally binding international climate change treaty. Limiting warming to 1.5°C (2.7°F) will significantly reduce the losses, damages, and deaths from climate change, according to the UN.

“Years of grossly insufficient action from richer nations and continued climate deception and obstruction by fossil fuel interests are directly responsible for bringing us here.”

This year’s report found that though the predicted global temperature increase has fallen slightly since last year, and the emissions gap has narrowed, improvements were not nearly enough to avoid serious climate consequences. Additionally, the formal withdrawal of the United States from the Paris Agreement in January is expected to wipe out 0.1°C (0.18°F) of projected improvements. 

Even if every pledged country’s plans to reduce emissions (called Nationally Determined Contributions, or NDCs) are fully realized, the world is still projected to warm up to 2.5°C (4.5°F) by 2100.  

The “ambition and action” that was expected from countries’ updated climate pledges this year “did not materialize,” Inger Andersen, executive director of UNEP, wrote in the report.

The report’s findings are “alarming, enraging and heart-breaking,” said Rachel Cleetus, senior policy director for the Climate and Energy Program at the Union of Concerned Scientists, in a statement. “Years of grossly insufficient action from richer nations and continued climate deception and obstruction by fossil fuel interests are directly responsible for bringing us here.”

The report finds that the world is virtually certain to exceed 1.5°C (2.7°F) of warming by 2100 if current policies continue (data suggests it already has, temporarily), and that there’s just a 21% chance of staying below 1.5°C (2.7°F) if current NDCs and net-zero pledges are realized. Keeping average global warming under 1.5°C (2.7°F) remains technically possible, but requires an ambitious global emissions cut of 55% from 2019 emissions levels by 2035, according to the report.

 
Related

•  Read the Emissions Gap Report 2025: Off Target
•  U.N. Sees Slight Progress on Climate Action, Partly Offset by the U.S.
•  Union of Concerned Scientists: UN Report Confirms Planetary Warming Will Breach 1.5 Degrees Celsius, Richer Nations Primarily to Blame
•  1.5°C: What It Means and Why It Matters
•  Get Involved: AGU Science Policy Action Center
 

Current NDCs “have barely moved the needle,” the authors wrote.

The past year was another record-breaking year for the climate, with multiple annual reports on climate change finding concerning climate indicators reaching record-breaking levels. Ocean heat and wildfire-related tree cover loss are at all-time highs, deadly weather disasters have surged, and atmospheric warming is showing signs of acceleration. Global greenhouse gas emissions in 2024 were 2.3% higher than in 2023, more than four times higher than the annual average growth rate.

A Lack of Ambition 

The Emissions Gap Report, along with other climate change reports released in October, is expected to inform discussions at the annual UN Framework Convention on Climate Change Conference of the Parties (COP30), which will begin next week in Belém, Brazil. 

These annual conferences are notorious for falling short of global climate goals, and a challenging geopolitical environment could make ambitious action even less likely. Political will worldwide is lacking—fewer than one-third of parties to the Paris Agreement even submitted their required updates to their emissions reduction plans by this year’s September deadline. 

“This is where the new jobs are, this is where the economy goes…this is where the future lies.”

These new NDCs “have done little to increase ambition,” the report states. Some countries’ newly submitted NDCs are less ambitious than their current policies’ emissions projections.

Still, low-carbon technology, climate governance frameworks, and progress on climate legislation have advanced substantially, and “these developments position the international community far more favourably to accelerate climate ambition and action than a decade ago,” the authors wrote.

While such acceleration is urgent, it also “makes sense,” Andersen said in a press conference. “This is where the new jobs are, this is where the economy goes … this is where the future lies.”

Andersen called on leaders at COP30 to understand that it falls upon them to pick up the work of climate mitigation and deliver on Paris Agreement targets.

—Grace van Deelen (@gvd.bsky.social), Staff Writer

These updates are made possible through information from the scientific community. Do you have a story about science or scientists? Send us a tip at eos@agu.org. Text © 2025. AGU. CC BY-NC-ND 3.0
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A seemingly unending sheet of ice covers most of Antarctica, but there’s a hidden network of liquid lakes lying beneath. These subglacial lakes affect the flow of the Antarctic Ice Sheet, which in turn dictates how rapidly ice enters the ocean and contributes to global sea level rise.

Researchers recently discovered 85 previously unknown subglacial lakes in Antarctica in which water levels are changing. These results, which boost the number of active lakes tabulated under the White Continent by nearly 60%, were published in Nature Communications.

Way, Way Down

“The whole column of ice above the lake needs to go somewhere.”

Subglacial lakes exist at the interface between the bottom of the ice and the continent’s underlying bedrock. The average thickness of the Antarctic Ice Sheet is roughly 4,000 meters, so subglacial lakes in Antarctica are way down there, said Sally Wilson, lead author of the paper and a glaciologist at the University of Leeds in the United Kingdom. “These lakes are really deep.”

Their waters don’t freeze, thanks to gentle frictional heating from the movement of the Antarctic Ice Sheet and also from heat imparted from Earth’s interior.

Wilson and her colleagues recently used satellite data to look for signs of Antarctic subglacial lakes. The researchers mined archival data collected by CryoSat-2, a European Space Agency satellite launched in 2010 to measure changes in the thickness of polar ice sheets. The team looked for changes in the height of the ice surface caused by subglacial lakes either filling or draining. “When they fill, the ice surface above the lake moves up. The whole column of ice above the lake needs to go somewhere,” said Wilson. “It’s kind of like a blister under the ice sheet.”

A Census of Lake Activity

Wilson and her collaborators analyzed CryoSat-2 radar altimetry data collected from 2010 to 2020 over the margins of Antarctica. The vertical resolution of CryoSat-2 data is a few centimeters at best, and the team found 85 regions that changed in height not by centimeters but rather by meters. Those robust signals very likely correspond to active subglacial lakes, the team concluded.

A new study relying on archival CryoSat-2 data identified 85 lakes beneath the Antarctic Ice Sheet. Credit: ESA (Data source: Wilson, S. et al., 2025)/ESA

That makes sense, said Leigh Stearns, a glaciologist at the University of Pennsylvania in Philadelphia who was not involved in the research. “There’s really nothing else that could cause the kinds of elevation changes that they’re seeing.”

Wilson and her colleagues found that 50 of the lakes they discovered exhibited both filling and draining behavior. And 10 of those lakes exhibited a complete cycle of filling and draining. On average, it took several years for lakes to fill and also several years for them to drain, the team noted.

To their surprise, the researchers found that individual lakes didn’t always fill and drain to the same level. The ice above a lake known as Whillans_180 in West Antarctica, for instance, uplifted, then subsided, then uplifted again by roughly 5 meters. However, after this consistent pattern, the ice then subsided only by about half that amount before beginning to uplift yet again, Wilson and her colleagues found.

The team also noted five regions across Antarctica where the lakes they discovered appeared to be connected. The researchers inferred such a connection by observing upstream draining events in some lakes that were nearly contemporaneous with downstream filling events in other nearby lakes.

These observations hint at a complicated hydrological network beneath the Antarctic Ice Sheet, said Wilson. Tracing how water moves under ice has long been a holy grail of polar science, she said. “Identifying the lakes is one thing. But actually tracking the movement of water is an entirely different ball game.”

Have Lakes, Will Lubricate

Water flowing from subglacial lakes can have a significant effect on glaciers in the vicinity. “It can lubricate the bed of the glacier and potentially make it flow faster,” said Wilson. “That contributes to sea level rise.”

“Being able to look at something on the surface to infer what’s happening at the bed is really exciting.”

The freshwater present in subglacial lakes can also change local ocean currents when it eventually drains to the ocean. The mere presence of freshwater can furthermore affect the many marine organisms that live around an ice shelf, said Wilson.

Finding these new subglacial lakes offers a window of sorts into what’s happening deep beneath the Antarctic Ice Sheet, said Stearns. “Being able to look at something on the surface to infer what’s happening at the bed is really exciting.”

An unexpected trove of archival satellite data made this work possible, Wilson and her collaborators noted.

CryoSat-2 in particular has vastly over-delivered—its nominal mission was supposed to be only three and a half years; it’s still going strong, more than 15 years later. “It’s way outlasted its expected mission lifetime,” said Wilson. Such long-term records are particularly valuable because they can be used to trace gradual changes in polar regions, she said.

“We should be putting money and effort into keeping these datasets alive.”

—Katherine Kornei (@KatherineKornei), Science Writer

Citation: Kornei, K. (2025), Satellite data reveal changing lakes under Antarctic ice, Eos, 106, https://doi.org/10.1029/2025EO250412. Published on 4 November 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
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Source: Journal of Geophysical Research: Planets

Trapped in a gravitational push and pull between Jupiter and other Jovian moons, Io is constantly being stretched and compressed. Heat generated by these contortions has melted pockets of the moon’s interior so much that Io is our solar system’s most volcanically active body.

The James Webb Space Telescope (JWST) recently opened up new opportunities to get to know Io. Using data from its Near Infrared Spectrograph—which sees wavelengths corresponding to different compositions and temperatures—de Pater et al. have made new discoveries about Io’s volcanoes and atmosphere.

The researchers first looked at Io in November 2022 and found an extremely energetic volcanic eruption in the vicinity of the lava flow field Kanehekili Fluctus. These observations revealed, for the first time, that some volcanoes on Io emit an excited form of sulfur monoxide gas, confirming the team’s 2-decade-old hypothesis. JWST also detected an increase in thermal emissions at the massive lava lake in Loki Patera, generated by the lake’s thick, solid surface crust sinking into the molten lava beneath.

Nine months later, in August 2023, the researchers had another chance to peer at the same two regions on Io with JWST. Just as in 2022, Io was in Jupiter’s shadow, making it possible to capture emissions at wavelengths that might otherwise be obscured by sunlight.

The new images captured infrared thermal emissions from the same two regions. However, lava flows from the 2022 Kanehekili region’s eruption had spread to cover more than 4,300 square kilometers—about 4 times the area they covered in 2022. At Loki Patera, a new crust had formed and cooled, in keeping with the lake’s behavior over the past few decades.

The new images also captured sulfur monoxide emissions in Io’s atmosphere above Kanehekili Fluctus—as well as above two other regions without a clear volcanic association, which the researchers attribute to “stealth volcanism.” In another first, the 2023 images revealed sulfur gas emissions at wavelengths never before seen in Io’s atmosphere. Instead of being concentrated in patchy spots like the sulfur monoxide was, the sulfur gas was distributed more evenly across part of the northern hemisphere.

The data suggest that these sulfur emissions did not come from sulfur atoms spewed out of volcanoes but were mainly produced by electrons from Io’s plasma torus—an area around its orbit with high levels of charged particles—penetrating Io’s mostly sulfur dioxide atmosphere and thereby exciting sulfur atoms upon impact. The angle at which JWST observed Io, combined with the northern hemisphere’s location relative to the plasma torus, explained why the detected emissions were concentrated over the northern hemisphere. Alongside data from the Keck Observatory and the Hubble Space Telescope, the new findings suggest this plasma torus–atmosphere system remains quite stable over decades. (Journal of Geophysical Research: Planets, https://doi.org/10.1029/2024JE008850, 2025)

—Sarah Stanley, Science Writer

Citation: Stanley, S. (2025), Webb Telescope spies Io’s volcanic activity and sulfurous atmosphere, Eos, 106, https://doi.org/10.1029/2025EO250366. Published on 4 November 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Space Weather

Space weather impacts caused by interplanetary disturbances of solar origin, such as coronal mass ejections, are coupled to Earth’s ionized upper atmosphere by electric currents travelling along magnetic field lines (field-aligned currents). These have historically been difficult to routinely measure with high spatial resolution of global coverage, with the best global monitoring to date from the AMPERE project, driven by IRIDIUM-Next telecommunications satellite data (drawn from six orbital planes).

In recent years, the number of satellites in low-Earth orbit has increased significantly; the OneWeb constellation has seen over 1,300 additional launches from 2019 to 2024. This recent mega-constellation uses 12 orbital planes, with a tighter distribution of satellites along each orbital plane.

By using the engineering data from these satellites, Archer et al. [2025] demonstrate that this data set can be used to derive global field-aligned currents at unprecedented resolution, showing that non-science grade instrumentation and commercial satellites have enormous potential scientific utility. The work performed here also highlights the challenges that need to be addressed with industry partners if the scientific community is to enable further advances with these platforms, and in turn provide datasets for space weather research and operations applications, helping protect critical infrastructure.

Citation: Archer, M. O., Evans, V., Eastwood, J. P., Camus, L.-A., Waters, C. L., Brown, P., & Armogathe, F. (2025). First detection of field-aligned currents using engineering magnetometers from the OneWeb mega-constellation. Space Weather, 23, e2025SW004573. https://doi.org/10.1029/2025SW004573

—Steven K. Morley, Editor, Space Weather

Text © 2025. The authors. CC BY-NC-ND 3.0
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Author(s): S. Isayama, S. Matsukiyo, T. Sano, and S. H. Chen

This study addresses particle acceleration up to relativistic energies via a nonlinear evolution of a large-amplitude Alfvén wave. A multistage process is observed in numerical particle-in-cell simulations. The results provide insights into coherent wave-particle interactions in collisionless plasmas with potential implications for the understanding of high-energy cosmic-ray generation in astrophysical environments such as pulsar magnetospheres, accretion disks, and relativistic jets.

#AdvancingField

[Phys. Rev. E 112, 055201] Published Tue Nov 04, 2025