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SummaryOcean-bottom seismometers (OBSs) are reliable instruments to record ground motions and acoustic signals on the sea floor. Precise timing of the data is essential for most seismological analyses. The internal clocks of the OBSs are not GNSS-controlled, so the clock drift mainly caused by ageing of the quartz crystal and temperature effects must be corrected. As part of the BRAVOSEIS experiment, eight OBSs were deployed in the Antarctic Bransfield Strait for 13 months. All OBSs suffered from a large (-15.3 to 5.4 s) and non-linear (-1.2 to -0.6 s residual to linear drift) clock drift. We used noise cross-correlations to determine the clock drift. The parameters for data pre- and post-processing such as filtering and normalisation had to be selected carefully. Overlapping correlation windows were stacked to derive daily Green’s functions. The time shift between consecutive days was calculated and distributed linearly over the data to obtain a continuous data set without gaps or overlaps. Airgun shots were used to constrain the cumulative clock drift of one station without initial synchronisation. Two onshore stations served as GNSS-controlled reference for four OBSs in the northern part of the Central Bransfield Basin. A different noise regime prevailed in the southern part of the basin; therefore, two already corrected OBSs from the northern part were used as reference stations for the southern OBSs. In this way, the clock drift of all OBSs could be corrected accurately.

SummarySpectral induced polarization (SIP) is a promising technique for detecting microbial activity in porous media, yet its interpretation remains limited by the absence of mechanistic models that account for microbial cell structure. In this study, we present a new semi-analytical model for the electrical polarization of microbial cells that treats both the cell plasma and the surrounding medium as electrolytes, and accounts for the cell membrane as well as the influence of the charged surface structures of the cell. We validate our model through numerical simulations based on the Poisson–Nernst–Planck equations. The model builds upon the membrane capacitance model by Sun and Morgan and integrates surface conductivity effects via the O’Konski model and low-frequency polarization using an adapted Dukhin–Shilov approach. The agreement between the numerical results and our new semi-analytical model is good. The model accounts for three dominant polarization mechanisms: (1) diffuse layer polarization at low frequencies (102–104 Hz), (2) membrane-related capacitive effects at intermediate frequencies (105–107 Hz), and (3) Maxwell-Wagner-type polarization at high frequencies (107–109 Hz). In experimental studies, polarization of bacteria typically appears at frequencies around 0.05 and 20 Hz. As the characteristic frequency of polarization processes usually decreases with increasing polarization length scales, the remaining discrepancy between model and experimental observations suggests that measured signals may be influenced by cell aggregates, biofilms, or metabolic byproducts. Our findings provide a foundation for a mechanistic understanding of microbial polarization and highlight the need for future work to extend the model to conglomerates of microbial cells.

Minerals form the building blocks of almost everything on Earth. They are made up of crystals—regular, repeating atomic structures that fit together like a three-dimensional pattern. When minerals deform, their normally ordered crystal lattices develop linear imperfections known as dislocations. These are small breaks or shifts in the atomic arrangement that allow crystals to change shape under stress. Some deformed crystals contain large numbers of dislocations, while in others they are sparse and searching for them is like looking for a needle in a haystack.

While most of the world's glaciers are retreating as the climate warms, a small but significant population behaves very differently—and the consequences can be severe. A team of international scientists, led by the University of Portsmouth, has carried out a comprehensive global analysis of surging glaciers, examining the hazards they cause and how climate change is fundamentally altering when and where these dramatic events occur.

Publication date: Available online 10 February 2026

Source: Advances in Space Research

Author(s): Khiri Abubakr Khalf, Teoh Ying Jia, Nordiana Mohd Muztaza, Nur Azwin Ismail, Abdulrahman Idris Augie, Abdulrasheed Adamu Hassan, Sirajo Abubakar, Sadiq Bukar Musty

Publication date: Available online 10 February 2026

Source: Advances in Space Research

Author(s): D. Sierra-Porta, Maximiliano Canedo Verdugo, Daniel David Herrera Acevedo

Publication date: Available online 9 February 2026

Source: Advances in Space Research

Author(s): Guoyu Li, Yu Cao, Samantha L. Lima, Hang Chen, Yangfei Huang, Bryan C. Pijanowski

Publication date: Available online 9 February 2026

Source: Advances in Space Research

Author(s): Yanpu Mu, Hao Fu, Yizhen Zheng, Yuefeng Li, Xudong Pan

It is well documented that the Gulf Stream plays a pivotal role in the climate system through its transfer of heat, which ultimately supplies warmth to northern latitudes in the North Atlantic. What remains less well understood is how the Gulf Stream influences the climate system by transporting nutrients and carbon. These materials stimulate plankton growth, which in turn plays a vital role in naturally absorbing carbon dioxide from the atmosphere.

There's been a seismic shift in science, with scientists developing new AI tools and applying AI to just about any question that can be asked. Researchers are now putting actual seismic waves to work, using data from the world's largest repository of earthquake data to develop "SeisModal," an AI foundation model designed to explore big questions about science. The effort, known as Steel Thread, involves researchers from five national laboratories operated by the U.S. Department of Energy.

For obvious reasons, it would be useful to predict when an earthquake is going to occur. It has long been suspected that large quakes in the Himalayas follow a fairly predictable cycle, but nature, as it turns out, is not so accommodating. A new study published in the journal Science Advances shows that massive earthquakes are just as random as small ones. A team of researchers led by Zakaria Ghazoui-Schaus at the British Antarctic Survey reached this conclusion after analyzing sediments from Lake Rara in Western Nepal.

Bright streaks of material trickle down the slopes of many of Mercury’s craters, but scientists have struggled to understand how these geologically young features, called slope lineae, appeared on a seemingly dead world. Now, researchers have used machine learning to analyze more than 400 slope lineae in the hope of understanding the streaks’ origin.

The analysis of images from NASA’s decade-gone MESSENGER (Mercury Surface, Space Environment, Geochemistry, and Ranging) mission showed that lineae seem to stream from bright hollows on the sunward side of crater slopes and mainly appear on craters that punched through a thin volcanic crust to a volatile-rich layer beneath. The lineae, the team theorized, could have formed when that exposed layer heated up and released volatiles like sulfur to drip downslope.

“We have these modern data science approaches now—machine learning, deep learning—that help us look into all those old data sets and find completely new science discoveries in them,” said Valentin Bickel, a planetary geomorphologist at Universität Bern in Switzerland and lead researcher on the study.

Streaks and Stripes

MESSENGER orbited Mercury from 2011 to 2015, and observations from those 4 years remain some of the best data we have on our solar system’s smallest planet.

The images revealed that although there is not a lot of geologic activity happening today, the planet remains chock-full of oddities.

One of those strange phenomena is the existence of slope lineae streaking down from the rims of many of Mercury’s craters. The higher-resolution MESSENGER images show that Mercury’s lineae are made of bright material and are geologically young, with crisply defined edges and no small craters superimposed on top. But planetary scientists had not conducted any systematic analysis of lineae before now, focusing instead on understanding the planet’s similarly bright, but more numerous, hollows.

“The first things we as geologists like to do is put things on a map.”

Bickel and his team sought to fill that knowledge gap. Their machine learning tool looked at more than 112,000 MESSENGER images with spatial resolutions finer than 150 meters (492 feet), identified 402 individual lineae, and cataloged their properties in a uniform way.

“The first things we as geologists like to do is put things on a map,” Bickel said.

Most of MESSENGER’s high-resolution images cover the northern hemisphere, Bickel explained, so most (93%) of the lineae the team cataloged were in the north. Ninety percent of lineae are located within craters. They are hundreds or thousands of meters long, are less than 20 meters (65 feet) tall, and are located on steeper-than-average crater slopes. Most lineae extend from young, bright hollows or hollow-like features.

But the most telling commonality among lineae is that they prefer the side of craters facing the equator, which is the side that receives the most sunlight.

The MESSENGER mission imaged slope lineae in Mercury’s craters on 1 August 2012 (left) and 19 October 2013 (right). Credit: NASA/JHUAPL/Carnegie Institution of Washington

That trend led the researchers to their theory of how lineae form. An impact exposes Mercury’s shallow but volatile-rich bedrock layer. Insolation, or heat from the Sun, draws out volatile gases in those rocks, and those volatiles then slowly drip down the crater wall, leaving bright deposits behind.

“The fact that lineae are on slopes that are facing the Sun implies that insolation might play a role in activating the process,” Bickel said. “And whenever insolation is so prominent, that implies that volatile material is involved. And in Mercury’s case has to come from the subsurface.”

The team published these results in Communications Earth and Environment.

Making a More Complete Map

Susan Conway, a planetary geomorphologist at the French National Centre for Scientific Research (CNRS) in Nantes, France, said planetary scientists have long accepted that Mercury’s hollows are produced by the loss of subsurface volatiles.

“Given that the slope lineae often originate at what appear to be hollows on the crater wall and have the same colour as them, the inference that slope lineae are also linked to volatile loss makes sense,” Conway wrote in an email.

Across the solar system, “slope lineae are pretty common,” added Conway, who was not involved with this research. “Several different kinds have been documented on Mars—slope streaks believed to be dust avalanches, recurring slope lineae whose formation is still debated and could be related to volatiles.” Granular flows on the Moon as well as lineae on Ceres and some icy moons in the outer solar system also resemble those on Mercury.

But a good 10% of Mercury’s known lineae don’t appear within craters, and conversely, there are plenty of craters with hollows that don’t have lineae. Other mechanisms are likely at work there, Bickel said.

“BepiColombo will image the whole surface at a resolution that would enable us to see most slope lineae.”

Thankfully, planetary scientists won’t have to wait long to test this theory. The BepiColombo spacecraft will arrive at Mercury in November and will begin science operations in early 2027. The joint mission from the European Space Agency and the Japan Aerospace Exploration Agency will image more of the planet’s surface than MESSENGER did and at a consistently higher spatial resolution.

Bickel and other Mercury scientists expect that BepiColombo will image more slope lineae across the planet, including smaller lineae, dimmer lineae, and lineae at southern latitudes. It will likely reimage some lineae-dense locations and reveal whether the streaks have changed in the 16 years since MESSENGER’s last images. And it may even capture repeat snapshots of a few locations, allowing scientists to see whether lineae change on short timescales.

“BepiColombo will image the whole surface at a resolution that would enable us to see most slope lineae,” Conway said. “We’ll get a complete picture of their spatial distribution, which will enable us to better test the volatile-driven hypothesis.”

—Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writer

Citation: Cartier, K. M. S. (2026), Oozing gas could be making stripes in Mercury’s craters, Eos, 107, https://doi.org/10.1029/2026EO260052. Published on 12 February 2026. Text © 2026. 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.

Fast ice, also called landfast sea ice, is a relatively short-lived ice that forms from frozen seawater and attaches like a “seatbelt” to larger ice sheets. It can create 50- to 200-kilometer-wide bands that last anywhere from a few weeks to a few decades and act as a site for valuable geochemical processes, breeding grounds for emperor penguins, and a protective buffer between caustic Antarctic winds and waters and inland bodies of ice.

In new research published in Nature Communications, scientists found that buried sediments can track the long-term growth of Antarctic fast ice—and that the ice’s freezing and thawing may be linked to cycles of solar activity. Given that this ice plays a significant role in protecting Antarctica’s larger ice sheets, the research could have major implications for understanding the ongoing impacts of climate change in Antarctica.

“Fast ice, especially in the summertime, is suffering the same fate as overall pack ice,” said Alex Fraser, a glaciologist at the University of Tasmania, who was not involved in the study. We’ve seen a “dramatic decrease” over the past decade, he said. “We’re down to around half of the ‘normal’ [amount].”

“To understand how humans are changing the planet, we first need to know how the planet changes on its own.”

Over the past several decades, the only way for scientists to track fast ice has been through satellite data, which can reveal the ice’s history over only the past 40 or so years. This narrow range has prohibited researchers from understanding the ice’s behavior prior to human-induced climate change.

“To understand how humans are changing the planet, we first need to know how the planet changes on its own,” said Mike Weber, a geoscientist at Universität Bonn in Germany and a coauthor of the study. The new work aimed to establish a “blueprint” for how fast ice behaves in the long term, allowing researchers to better understand how the ice contracts or expands when exposed to greenhouse gas emissions.

Sediment Secrets

To better understand fast ice history, the team turned to sediment cores from Victoria Land in eastern Antarctica. By scrutinizing laminated layers within the cores, the researchers were able to pinpoint key markers that correspond to ebbs and flows in fast ice going back 3,700 years.

The team found that lighter sediment layers formed during summer months marked by prolonged ice loss, whereas darker layers formed during regular seasonal thawing. They also found evidence that different species of small organisms called diatoms grew during summer months versus thawing periods, further enabling the science team to distinguish the cycles. By combining these and other data unearthed from the sediments, the researchers identified recurring periods of open-water and low-ice conditions pinned to solar cycles—called the Gleissberg and Suess-de Vries solar cycles—that occur approximately every 90 and 240 years, respectively.

The link to solar cycling was surprising at first, but the researchers suggested the explanation is straightforward: Solar activity can influence winds over the Southern Ocean, transporting warm air over the Victoria Land coast and leading to ice melt.

“Laminated sediments are always intriguing because you know they’re hiding a message.”

“Laminated sediments are always intriguing because you know they’re hiding a message,” said Tesi Tommaso, a biogeochemist at the National Research Council of Italy’s Institute of Polar Sciences and lead author of the study. “When we realized that over long timescales, this laminated pattern was linked to solar activity, it actually made perfect sense—it was super exciting.”

In future work, the team plans to dig up deeper sediment cores to push fast ice records back even further. The data would be “incredibly informative,” said Tommaso.

“We have finally developed a high-resolution ‘time machine’ for a critical but poorly understood part of Antarctica,” Weber said. “It’s a testament to how interconnected our atmosphere, ocean, and ice really are.”

—Taylor Mitchell Brown (@tmitchellbrown.bsky.social), Science Writer

Citation: Brown, T. M. (2026), Sediments offer an extended history of fast ice, Eos, 107, https://doi.org/10.1029/2026EO260054. Published on 12 February 2026. Text © 2026. 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.

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

Atmospheric conditions over Antarctica affect global climate cycles, and are thus critical for climate assessment. However, studying atmospheric changes in Antarctica is quite challenging as they are driven by a variety of processes at local scale not easily captured by global models. Monitoring seasonal atmospheric pressure changes is one way to keep track of the evolving Antarctic atmosphere.

Because changes in stratospheric conditions influence the flux of cosmic rays reaching Earth’s surface, Santos et al. [2025] use measurements from a water-Cherenkov cosmic-ray detector, to monitor variations in the 100-hPa geopotential height (about 15 kilometers) over the Antarctic Peninsula. After conducting a thorough statistical analysis of the data, the authors develop a simple model linking surface pressure and cosmic ray count data, validating it against observed ERA5 100-hPa geopotential height reanalysis data. The model is especially accurate in (southern hemisphere) spring, but it performs well also at other times of the year.

With their model, the authors demonstrate that water-Cherenkov cosmic-ray detectors can be reliably used as proxies for atmospheric pressure changes, thus adding a new, simple, and effective tool to monitor and study lower stratospheric dynamics over Antarctica.

Citation: Santos, N. A., Gómez, N., Dasso, S., Gulisano, A. M., Rubinstein, L., Pereira, M., et al. (2025). Cosmic ray counting variability from water-Cherenkov detectors as a proxy of stratospheric conditions in Antarctica. Earth and Space Science, 12, e2025EA004298. https://doi.org/10.1029/2025EA004298

  —Graziella Caprarelli, Editor-in-Chief, Earth and Space Science

Text © 2026. 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.

Geologists from St. Petersburg State University, as part of an international scientific team, have analyzed rock data from East Antarctica and determined that the magnetic anomaly in this region resulted from the convergence of continents and the birth of the supercontinent Rodinia approximately 1 billion years ago. The research is published in the journal Polar Science.

AbstractHigh-frequency induced polarisation (HFIP) measurements enable quantification of ground ice content in frozen media by capturing ice relaxation within the frequency range of 1 to 100 kHz. Existing parameterised inversion approaches may bias results by imposing an ice relaxation signature where none exists, assuming a Cole-Cole-type response that may not reflect the true dielectric behaviour of ice, and neglecting low-frequency polarisation. These limitations can lead to high data misfits and ambiguities in interpretation. This study presents an alternative approach that applies independent frequency inversion to directly derive complex resistivity spectra from field measurements, avoiding reliance on predefined models. The resulting inverted spectra provide a representation that more closely captures the true subsurface response. A second, petrophysical, inversion is then performed by fitting a two-component mixture model to the inverted spectra, weighted by the volumetric fractions of its components. One of these components is ice, allowing for the estimation of the volumetric ice content. The approach was applied at Heliport Mire (Abisko, Sweden), a permafrost peatland site, using two complementary profiles: a 50-m 2D profile that captured broad lateral variations of frozen to unfrozen conditions, and an 8-m high-resolution 2D profile that resolved the vertical transition between the upper unfrozen and underlying frozen layers. Independent frequency inversion, across 1 Hz to 57 kHz, successfully produced smooth, coherent spectral responses of true resistivity and phase shift across both profiles. Petrophysical inversion results show diverse conditions along the profile, identifying three distinct zones: ice-rich frozen peat (40-77% ice content), a thawed or degraded peat region (<10% ice content), and unfrozen forest (<5% ice content, effectively representing ice-free conditions). HFIP-derived ice content values were consistent with those derived from laboratory measurements on a permafrost core extracted along the profile. The high-resolution profile distinctly identified the boundary between unfrozen and frozen ground, as confirmed by direct probing measurements. Additionally, the petrophysical model resolves parameters such as shape factor and matrix permittivity, offering further insight into subsurface properties. This methodology advances ground ice characterisation by providing robust quantitative estimates of ice content while retaining spectral information with broader interpretative potential.

Current global climate models (GCMs) support with high confidence the view that rising greenhouse gases and other anthropogenic forcings account for nearly all observed global surface warming—slightly above 1 °C—since the pre-industrial period (1850–1900). This is the conclusion presented in the IPCC's Sixth Assessment Report (AR6) published in 2021.

Geographic information system (GIS) maps help researchers, policymakers, and community members see how environmental risks are spread throughout a given region. These types of interactive, layered maps can be used for storytelling, education, and environmental activism. When community members are involved in their use and creation, GIS maps can also be a tool for equity.

A new study reports that climate warming can increase soil carbon accumulation in boreal Sphagnum peatlands by boosting plant productivity, protecting iron, and inhibiting microbial decomposition. These responses contrast sharply with warming-enhanced soil carbon mineralization—the process by which carbon is released as CO2—in boreal forests and tundra. Together, these contrasting processes highlight the vital yet often overlooked role of Sphagnum peatlands in counteracting boreal carbon loss under future warming.

UK winters are becoming significantly wetter mainly due to warming driven by human burning of fossil fuels releasing greenhouse gases into the atmosphere, a Newcastle University study reveals. The research shows that for every degree of global or regional warming, winter rainfall increases by a compounding 7%, increasing the risk of flooding. And the scientists warn it is happening much faster than most global climate models predict.