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Forecasting volcanic eruptions in time to alert authorities and populations remains a major global challenge. In a study published in Nature Communications, researchers and engineers from the Institut de Physique du Globe de Paris (IPGP) and the GFZ Helmholtz Centre for Geosciences present a new detection method, called "Jerk," using a single broadband seismometer. It is capable of identifying, in real time, very early precursor signals of volcanic eruptions generated by subtle ground movements associated with magma intrusions.

For decades, families in communities around Johannesburg have been living close to huge gold mining waste dumps. For many residents, the dust that is released there is just part of everyday life—but it can contain natural uranium compounds that come to the surface with the mined rock. A new study in the journal Environmental Geochemistry and Health reveals how this exposure is reflected in children's hair.

People living on the low-lying shores of the Bristol Channel and Severn estuary began their day like any other on January 30, 1607. The weather was calm. The sky was bright.

The King's Trough Complex is a several-hundred-kilometer-long, canyon-like system of trenches on the North Atlantic seafloor. Its formation was long thought to be the result of simple stretching of the oceanic crust. An international research team led by the GEOMAR Helmholtz Center for Ocean Research Kiel has now shown that the so-called "Grand Canyon of the Atlantic" was formed about 37 to 24 million years ago through the interplay of a temporarily existing plate boundary and an early branch of the Azores mantle plume. Their findings have been published in the journal Geochemistry, Geophysics, Geosystems.

To reduce air pollution associated with ocean transport, the International Maritime Organization tightened restrictions on sulfur content in ship fuel, resulting in an 80% reduction in emissions by 2020. That shift created an inadvertent real-world experiment in how man-made aerosols influence cloud formation over the ocean.

When most of us look out at the ocean, we see a mostly flat blue surface stretching to the horizon. It's easy to imagine the sea beneath as calm and largely static—a massive, still abyss far removed from everyday experience.

Wetlands make up only about 6% of the land area but contain about 30% of the terrestrial organic carbon pool. Therefore, CO2 emissions from wetlands are central to the global climate balance. In Denmark, the plan is to flood 140,000 hectares of low-lying land such as bogs and meadows as part of the Green Tripartite Agreement. Flooding such areas will slow down the decomposition of organic material in the soil and keep the CO2 in the soil rather than allowing it to be released to the atmosphere and contribute to the greenhouse effect. At least, that has been the rationale until now.

A new study suggests the world's oxygen-depleted seas may have a chance of returning to higher oxygen concentrations in the centuries to come, despite our increasingly warming climate.

The vital role apex predators play in maintaining healthy ecosystems is well-documented, but research published in Scientific Reports suggests predators might also influence the global carbon cycle. The study found that across coastal wetlands in the southeastern United States, soils store more carbon where American alligators are present, linking predator recovery to enhanced carbon retention in some of the planet’s most efficient natural carbon sinks.

Wetland carbon storage (so-called “blue carbon”) is facilitated by wetlands’ waterlogged, oxygen-poor soils, which slow decomposition and allow organic material to accumulate over time. Scientists know that when wetlands are drained or degraded, stored carbon can be released into the atmosphere as carbon dioxide. Less well understood is how biological interactions within these habitats shape carbon dynamics. The new study adds to a growing body of evidence showing that animals—particularly apex predators—can influence vegetation, soils, sediment flows, and nutrient cycles at scales large enough to affect the planet’s carbon budget.

“What we found was a positive correlation between alligator abundance and carbon sequestration in specific habitats,” said Christopher Murray, an ecologist at Southeastern Louisiana University and lead author of the study. “Where we have more alligators, from small populations to much larger populations, we actually see higher carbon sequestration.”

Across the alligator’s native range, wetlands stored an average of 0.16 gram more carbon per square centimeter in the top 10 centimeters of soil when alligators were present.

Murray and his colleagues at Southeastern and the Louisiana Universities Marine Consortium analyzed soil carbon data from the Smithsonian’s Coastal Carbon Network. From that database, the team selected 649 continuous soil cores from tidally influenced wetlands in 13 states. They compared those carbon measurements with data on alligator presence, density, and nesting patterns assembled from state wildlife agencies and long-running monitoring programs.

Across the alligator’s native range, wetlands stored an average of 0.16 gram more carbon per square centimeter in the top 10 centimeters of soil when alligators were present. That surface layer reflects relatively recent carbon accumulation over roughly the past 6 decades. This period overlaps with the recovery of alligator populations following the Endangered Species Protection Act of 1966.  

The researchers attribute the observed patterns to a combination of physical ecosystem engineering and trophic cascades, or actions by predators that reverberate through multiple layers of a food web. As apex predators, alligators may suppress herbivore populations that otherwise damage vegetation and disturb soils, potentially allowing denser plant growth and greater carbon burial. Alligators also modify wetland landscapes directly. By digging dens, carving channels, and creating small ponds, they reshape hydrology, redistribute sediments and nutrients, and create localized microhabitats where organic carbon can accumulate and persist.

Trophic Effects

At a continental scale—spanning a wide range of coastal wetland types across multiple states—the study found no statistically significant difference in carbon storage between sites with and without alligators. The authors suggest that this reflects substantial ecological variability across regions, including differences in vegetation, geomorphology, hydrology, and food web structure, which can mask the influence of any single predator species when ecosystems are analyzed collectively.

An American alligator rests on a fallen tree. Research suggests that wetlands within the alligator’s native range store more carbon in surface soils when alligators are present. Credit: Emil Siekkinen

“Originally, I was surprised by that finding,” said Murray. The team’s original hypothesis predicted higher carbon sequestration wherever alligators were present, consistent with trophic cascade theory. The absence of a clear continental-scale signal, Murray said, made it obvious to him, “later on, that there’s a different apex predator that is working in those habitats.”

When the analysis was narrowed to the alligator’s native range, thereby reducing ecological variability, the pattern became clearer. At these regional scales, wetlands with alligators consistently stored more carbon, suggesting that in ecosystems where they occupy the top trophic position, alligators may exert a detectable influence on wetland carbon dynamics.

“Apex predators like crocodilians have a critical role in the function of our world.”

 “This study is important because it links an apex predator directly to wetland soil carbon stocks, moving beyond theory to show that food web structure can shape carbon outcomes at ecosystem scales,” marine ecologist and Blue Carbon Lab director Peter Macreadie, who was not involved in the study, wrote in an email. “It also challenges prevailing blue carbon approaches by showing that long-term carbon storage depends not only on vegetation and sediments, but on maintaining intact trophic interactions.”

Such trophic effects help explain how sea otters maintain kelp forests by controlling sea urchins and why wolves have been linked to forest regeneration through changes in large herbivore behavior. The alligator study suggests that similar processes may operate in coastal wetlands, where predator presence supports vegetation growth, soil stability, and carbon retention.

The study does not establish causation, and Murray emphasized that long-term exclusion experiments would be needed to directly test how changes in alligator populations affect carbon accumulation over time. Even so, the findings suggest that predator recovery may have consequences for the climate that are rarely considered in conservation planning. Murray said that the implications of this work extend beyond carbon accounting, however. “Apex predators like crocodilians have a critical role in the function of our world,” he said. “And they should be respected rather than feared.”

—Emil Siekkinen, Science Writer

Citation: Siekkinen, E. (2026), Alligators may boost carbon storage in coastal wetlands, Eos, 107, https://doi.org/10.1029/2026EO260038. Published on 29 January 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.

In countries of the far north, a particular kind of natural disaster can strike almost without warning. Quick clay landslides, in which previously solid soil suddenly liquefies, can carry away houses and farms and bury towns and roads. The slides occur when salts leach out from clay soils that were previously beneath sea level, eventually bringing the soils’ stability beneath a critical threshold and making them vulnerable to potential triggering events.

“If we can understand how these salts are doing it, maybe we can find something else that does the same thing.”

Striking examples in Norway include buildings sliding sideways into the sea near the northern town of Alta in 2020 and the Verdal landslide in 1893, in which 3 square kilometers of land broke loose in the central Norwegian municipality, killing 116 people and burying 105 farms. Quick clay (often called sensitive clay in North America) is also found in Alaska, as well as Canada, Finland, Russia, and Sweden, where governments often attempt to stabilize at-risk soils. Doing so can be expensive and environmentally harmful, leading researchers to seek better ways of making quick clay safe again.

In new research published in the Journal of Colloid and Interface Science, Norwegian researchers dove down to the microscopic scale to provide new insights into how different kinds of salts contribute to the mechanical strength of quick clay. The findings could reveal novel ways to make at-risk soils safe from slides, said study coauthor Astrid de Wijn, a materials scientist at the Norwegian University of Science and Technology (NTNU).

“If we can understand how these salts are doing it, maybe we can find something else that does the same thing,” she said.

For Want of Salt

The key statistic for quick clay risk is the marine limit—the line dividing soils that were previously below sea level from those that remained above it. In high-latitude countries like Norway, melting glaciers at the end of the last ice age, around 10,000 years ago, caused a process of unburdening and uplift called isostatic rebound that brought some previously submerged areas above water. The marine limit varies from place to place but can be more than 200 meters above current sea levels in the south of Norway and includes significant portions of the country.

The soil “will behave like sort of a sour cream. It just pours out of the landslide crater.”

Soils beneath the marine limit were infused with salts from the sea, which they’ve gradually lost over time from groundwater leaching. Those salt ions act as electrochemical binders between clay molecules, helping strengthen them, said Jean-Sébastien L’Heureux, a geotechnical engineer and technical expert on quick clay at the Norwegian Geotechnical Institute who was not involved with the research.

Without the salts to hold them, the microscopic particles of clay look more like a house of cards, stacked haphazardly with nothing binding them together. It is in this state that regular clay becomes quick clay, where even small perturbations like minor earthquakes or construction projects can cause devastating landslides. Previously solid soil “will behave like sort of a sour cream,” L’Heureux said. “It just pours out of the landslide crater.”

The main way to prevent such catastrophes is to stabilize the soil, a process that to date has typically involved injecting lime and cement to act as a binder. The technique is effective but environmentally unfriendly because of the large amounts of carbon dioxide (CO2) it creates. Coming up with an equally effective, more sustainable method is the goal of the Sustainable Stable Ground (SSG) project run by NTNU, which de Wijn and her coauthor, NTNU chemist Ge Li, are part of.

Using molecular dynamics simulations that re-create how clay molecules act at the nanoscale, the two researchers were able to compare how different salt cations affected the clay’s strength. The key difference was between divalent cations like magnesium chloride (MgCl2) and calcium chloride (CaCl2) and monovalent ones like sodium chloride (NaCl) and potassium chloride (KCl), Li said. Divalent cations enhance interactions between clay particles to a greater extent and stick out more, increasing friction. That means they enhance clay strength more than monovalent cations do and could offer a blueprint for future chemical stabilizers in quick clay.

In Search of Better Solutions

Finding a truly effective, affordable, and sustainable means of stabilizing quick clay will likely take some time, however. Priscilla Paniagua, a geotechnical engineer at the Norwegian Geotechnical Institute not affiliated with the paper, noted that simply adding more salt, as some projects have attempted to do, is unlikely to be effective, as current technology makes it difficult to scale. What’s more, the salt will simply leach out from the soils again, Li noted.

Some teams have proposed using materials like biochar or ash to stabilize soils, approaches that work well in the lab but have yet to be scaled up, Paniagua said. Another issue is that some proposed stabilization methods would increase only the remolded strength of quick clay, or its strength after it has liquefied and begun moving.

“It means that it won’t be quick [clay], but…you’re not increasing the full stability of the slope,” L’Heureux said. Such approaches would mitigate the impact of a quick clay landslide but wouldn’t prevent it from occurring.

Though challenges remain, Li and de Wijn remain hopeful that a better solution for quick clay is possible. Li said their modeling work is informing small-scale lab experiments testing how various materials affect soil strength. New proposals for stabilizers include polymers that enhance clay binding and even CO2 injected into the soil to help lime solidify, de Wijn said.

Today, better maps of quick clay landslide risk give local governments and developers more information about where it’s safe to build and where it isn’t. But with many soils destabilized, scientists note, the risk of landslides remains.

—Nathaniel Scharping (@nathanielscharp), Science Writer

Citation: Scharping, N. (2026), Insights for making quick clay landslides less quick, Eos, 107, https://doi.org/10.1029/2026EO260040. Published on 29 January 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.

SummaryIn arid and semi-arid climates, it is critical to assess the state of the soil in terms of water content and water salinity. The use of geophysics, and geoelectrical methods in particular, to this end faces the challenge of discriminating between the effects of water content and pore water salinity on soil electrical resistivity, since these two factors are both inversely related to resistivity. The heterogeneity of soils, with its possible varying clay content, makes the interpretation even more complex. We have investigated the combined effect of water saturation, pore water salinity and clay content using Spectral Induced Polarization (SIP) on controlled laboratory samples. The experiments contribute to the development and application of the SIP method in the area of small-scale data acquisition and processing for hydrogeophysical and environmental purposes. In our experimental setup the above-mentioned three variables were gradually modified under controlled conditions. Ca-montmorillonite and very fine to coarse sand were mixed during multiple dry-wet mixing cycles in order to create artificial soil samples that mimic natural soils. In total, 4 samples were used with clay content varying from 2 to 8 mass per cent of clay. The other two variables were changed as well: water saturation ranging from 100 per cent to 10 per cent in 9–15 steps, and electrical conductivity of the pore water ranging from 0.05 to 0.7 S m−1 in 4 steps. The statistical analysis of the results indicates that there is a significant positive correlation between quadrature conductivity and the three variables. The obtained data was fitted using a double Cole-Cole model. The analysis of the obtained Cole-Cole parameters along the three variables shows promising results for the separation between the effects of pore water salinity and water content, thus paving the way for fruitful field applications in arid and semi-arid environments.

SummaryIn the context of detecting shallow, localized seismic velocity variations, we assess the sensitivity of wavefield gradients, specifically normal strain and rotation, relative to traditional seismological observables such as displacement, velocity, and acceleration. We begin with a simple single-scattering analysis of the displacement wavefield and its gradient, and introduce the Proximity Field Test (PFT) as a straightforward and effective tool for subsurface detection. We then perform 3D elastic simulations with SEM46, a spectral-element code modified to directly output strain and rotation, and analyze two case studies involving localized shallow velocity changes in a homogeneous medium. In the first case, P- and S-wave velocities and density are varied by 10 per cent relative to the background, whereas in the second case the local velocity decrease is 70 per cent. By comparing waveforms in the reference medium with those obtained after introducing the heterogeneity, we show that the joint analysis of displacement and gradient measurements enables efficient detection of subsurface anomalies. Finally, we validate the approach with a field experiment combining geophones and DAS measurements, aimed at detecting a buried concrete foundation associated with an approximate 70 per cent positive velocity contrast in the shallow subsurface. The anomaly is clearly identified with minimal processing, demonstrating the practical potential of the proposed method.

A relatively simple statistical analysis method can more accurately predict the risk of landslides caused by heavy rain, according to a study coordinated by Brazilian researchers affiliated with the Institute of Mathematical and Computer Sciences at the University of São Paulo (ICMC-USP) in São Carlos and the National Institute for Space Research (INPE). The researchers have validated their strategy based on a real event.

In a critical advance for climate resilience, researchers from The Hong Kong University of Science and Technology (HKUST) have developed an AI model that can predict dangerous convective storms—including Black Rainstorms, thunderstorms and extreme heavy rainfall like those that have hit Hong Kong—up to four hours before they strike. This world-first technology, developed in collaboration with national meteorological institutions and powered by satellite data and advanced deep diffusion technology, improves forecast accuracy by over 15% at the 48-kilometer spatial scale compared with existing systems. This breakthrough strengthens the overall accuracy of the national weather forecasting system and promises to transform early warning systems for vulnerable communities across Asia.

A team of NASA scientists deployed on an international mission designed to better understand severe winter storms. The North American Upstream Feature-Resolving and Tropopause Uncertainty Reconnaissance Experiment, or NURTURE, is an airborne campaign that uses a suite of remote sensing instruments to collect atmospheric data on winter weather with a goal of improving the models that feed storm forecasts. This combination of instruments will also serve as a proxy to demonstrate the potential to collect similar observations from space.

Deforestation is having a more devastating effect on the Amazon rainforest than earlier data suggested. While cutting down large swaths of trees destroys vital habitats, it also harms the region's ability to generate its own rainfall. According to a new study published in the journal Nature, the Amazon could reach a tipping point and experience major forest dieback (where large areas of the rainforest dry out and turn into a savanna) sooner than previously thought.

Publication date: Available online 21 January 2026

Source: Advances in Space Research

Author(s): Meiling Xing, Bo Li, Wenhao Zhang, Guohong Li, Xiufeng Yang, Qiyue Liu, Qichao Zhao

Publication date: Available online 21 January 2026

Source: Advances in Space Research

Author(s): Yannick Sztamfater Garcia, Boris Krämer, Aaron J. Rosengren, Manuel Sanjurjo-Rivo, Joaquin Miguez

Publication date: Available online 21 January 2026

Source: Advances in Space Research

Author(s): Lei Zhang, Kai Li, Chengpan Tang, Xiaogong Hu, Fengchun Shu, Yan Yang

Publication date: Available online 21 January 2026

Source: Advances in Space Research

Author(s): Wenjie Su, Haichao Gui, Rui Zhong