Feed aggregator

A pair of US researchers have developed a new model to tackle a deceptively simple problem: how a small block of ice melts while floating in calm water. Using an advanced experimental setup, Daisuke Noto and Hugo Ulloa at the University of Pennsylvania have captured the intricate dynamics that underlie this everyday process—work that could ultimately pave the way for more accurate predictions of melting sea ice. The study has been published in Science Advances.

Roughly half a century ago, the burgeoning field of marine cartography revealed a curious sight: Mid-ocean ridges punctuate the seafloor, their geographic highs running over our planet like the seams on a baseball. These features mark where Earth’s tectonic plates are diverging and magma is upwelling.

Researchers sent a remotely operated vehicle (ROV) to a mid-ocean ridge system deep in the Norwegian Sea and discovered unusually high levels of molecular hydrogen dissolved in the hydrothermal fluids there. That hydrogen, which can help fuel microbial activity, is likely arising from the degradation of organic matter, the team concluded. These results were published in Communications Earth and Environment.

Pulling Apart

Many of our planet’s mountain ranges are built by the convergence of tectonic plates. But there are also regions on Earth where tectonic plates are diverging. In those places, magma from the planet’s interior is rising toward the surface. Many of those so-called spreading sites happen to be located in ocean basins, and the result is a mid-ocean ridge: a range of underwater volcanoes.

Thanks to their volcanic origin and underwater locales, mid-ocean ridges are characterized by a chemically potent amalgam of seawater, seafloor sediments, and magmatic material. But relatively few mid-ocean ridge systems have been explored in detail, partly because many lie beneath thousands of meters of water. “There’s still much more to learn about these systems,” said Alexander Diehl, a geochemist at MARUM – Center for Marine Environmental Sciences at the University of Bremen in Germany.

In 2022, a team led by MARUM researchers studied the Knipovich Ridge system off the coast of Svalbard. This mid-ocean ridge is known for being particularly slow spreading—its tectonic plates are diverging at only about 14 millimeters per year. (Fingernails grow about twice as fast.) Slow-spreading sites tend to get less research attention than fast-spreading sites, said Diehl. The reason is the latter tend to have larger supplies of upwelling magma and therefore more hydrothermal venting, he explained.

The 2022 cruise aboard the R/V Maria S. Merian revealed previously unknown fluid escape sites—including iconic black smokers—and an array of microbes that thrived in the utter absence of sunlight. Researchers used an ROV to collect hydrothermal fluids emanating from four vent sites along the Knipovich Ridge. Unfortunately, however, the sampling devices aboard the vehicle were not gas tight, and some of the dissolved gases escaped. “The concentrations of volatiles were not quantified correctly,” said Diehl.

A Second Chance

“They maintain pressure inside the sampler not only during recovery but also in the laboratory.”

But 2 years later, scientists got a second chance to visit the Knipovich Ridge. Diehl was one of the researchers who joined a 2024 cruise, again aboard R/V Maria S. Merian, to revisit the slow-spreading site. This time, the team brought gas-tight devices known as isobaric fluid samplers. “They maintain pressure inside the sampler not only during recovery but also in the laboratory,” said Diehl.

Diehl and his colleagues collected 160-milliliter samples of hydrothermal fluids from several vent sites on the Knipovich Ridge at a depth of roughly 3,000 meters. The team then analyzed the samples on board the R/V Maria S. Merian. The team recorded high levels of silica, alkaline pH levels, and low concentrations of metals like iron and manganese consistent with other hydrothermal systems where fluids circulate through sediments. But to their surprise they also noted unusually high levels of molecular hydrogen. There was more than twice the highest amount that had ever been recorded in any sediment-hosted hydrothermal vent.

Hydrogen is important to many life-forms in the deep ocean that don’t receive sunlight, said Jeff Seewald, a geochemist at the Woods Hole Oceanographic Institution in Woods Hole, Mass., not involved in the research. “A lot of organisms can use it.” (Seewald developed the concept for the isobaric fluid samplers that Diehl and his colleagues used on their 2024 cruise.)

A Double Whammy

Finding so much hydrogen on the Knipovich Ridge baffled Diehl and his team. High concentrations of hydrogen typically arise in hydrothermal systems dominated by ultramafic rocks from the mantle, whereas the vents that Diehl and his colleagues studied were surrounded by terrestrial sediments sloughed off from the fjords of Svalbard.

Diehl and his team ran computer simulations and found that the high concentrations of molecular hydrogen could be explained by terrestrial sediments. The culprit, the researchers concluded, was the degradation of organic matter entrained in those sediments. Those reactions likely played a role in producing much of the hydrogen the team measured.

“You could potentially generate a significant amount of hydrogen, which could then be utilized by microbes.”

The hydrothermal system on the Knipovich Ridge is a powerhouse of hydrogen production, Seewald said. Finding similar systems on ocean worlds could have implications for life beyond Earth, he added. “You could potentially generate a significant amount of hydrogen, which could then be utilized by microbes.”

In the future, Diehl hopes to join another cruise to return to the Knipovich Ridge. It’s a fascinating site to visit, even if only vicariously, he said. “It’s a lot of fun to sit behind the pilots of the ROV.”

—Katherine Kornei (@KatherineKornei), Science Writer

Citation: Kornei, K. (2026), A mid-ocean ridge in the Norwegian Sea pumps out hydrogen, Eos, 107, https://doi.org/10.1029/2026EO260045. Published on 3 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.

Just 1 gram of soil can host billions of microorganisms and thousands of species of bacteria, fungi, and viruses, some of which drive essential processes like nutrient cycling. Because soil is home to nearly 60% of all living organisms, from microbes to mammals, some researchers have described it as the most biodiverse habitat on Earth. Soil microbes can also affect human heath, including by harboring pathogens and contributing to the development of antibiotic resistance.

As the climate continues to change, soil and its many inhabitants are facing changes, too. Yet by some estimates, about 99% of soil microorganisms have not yet been studied.

“Soil is one of the last frontiers on Earth.”

“Soil is one of the last frontiers on Earth,” said biologist Ava Hoffman, a senior scientist at the Fred Hutch Cancer Center in Washington State.

A group of educators, researchers, and students from dozens of institutions have teamed up to create the first-of-its-kind soil microbiome map of the United States. Though the effort is in its preliminary stages, researchers have already cataloged more than 1,000 previously unknown strains of bacteria and other microbes. The team discussed the work in a commentary published in Nature Genetics.

By collecting samples from 40 sites across the country and analyzing them with DNA sequencing tools used in human genomic study, researchers are working to build a broader understanding of the microbial “dark matter” in the soil under our feet. At the same time, the project is connecting faculty and students into a nationwide network of soil researchers.

Soil Brings Us Together

During the early days of the COVID-19 pandemic, when community and connection were lacking, the members of the Genomic Data Science Community Network (GDSCN) met virtually. They wanted to create a research project that would excite faculty and students about genetics and data without requiring too much lab equipment, and they wondered how that might be done.

It would be done by sampling soil, said Hoffman, one of the study’s authors. “It was really a way to get faculty from all over the place involved and able to answer the questions they were interested in.”

The GDSCN created the BioDiversity and Informatics for Genomics Scholars (BioDIGS) initiative to address some of the knowledge gaps in soil biodiversity as well as train students and faculty in genomic data science by including participants from a range of institutions, from research-focused universities to community colleges.

Students at United Tribes Technical College collect soil samples at their campus in Bismarck, N.D. Credit: Emily Biggane

To take part in the project, participants are sent preassembled soil collection kits. Participants obtain permission to sample soil from their chosen sites—such as college campuses, parks, urban corridors, hiking trails, and spaces with local significance—and follow a specific protocol for sample collection. Students and faculty members then capture the GPS coordinates and images from each site and choose 16–24 sampling spots within a 100-meter area.

After collecting the soil, participants send their samples to Johns Hopkins University. From there, the samples are routed to labs at the Johns Hopkins School of Medicine and Cold Spring Harbor Laboratory in New York for genome sequencing and to the University of Delaware for chemical testing. Resulting data are uploaded to national research databases.

“One thing that is important is to bridge that disconnect between a sample as a data point on screen and its place of being: where it came from, how it got to the lab, and its story,” said cellular and molecular biologist Emily Biggane, one of the study’s authors and a research faculty member at the United Tribes Technical College’s Intertribal Research and Resource Center in North Dakota. “That connection is really important for our students. The land is something that’s honored and celebrated. Our students are very interested in learning about the soil that supports us.”

Unearthing Information

The soil sites sampled in the project ranged from the playgrounds and parks of Baltimore to a former Superfund site in Georgia, from urban Seattle to land under development at a college campus in Bismarck, N.D. “Understanding how different clades of bacteria vary across all our sites and how they vary with things like heavy metal concentration and pH and climate—that’s been pretty cool to see,” Hoffman said.

Continued sampling across these sites—and others that may become part of later incarnations of the project, as it continues to grow—can also help researchers understand how soil microbial communities respond to the effects of climate change. “Repeated sampling across sites in North America may help us to discover fragile soil ecosystems where microbial communities are undergoing rapid change,” Marie Schaedel, a soil microbiologist at Oregon State University who was not involved in the research, said in an email to Eos.

“At the end of the day, documenting soil biodiversity is not a problem that a single scientist can solve. We need a ton of people to do this.”

“Citizen science research like this benefits both science and society. It increases the amount of data on microbiomes in diverse soil habitats,” said Schaedel. “It also has the potential to motivate the next generation of researchers by making the research accessible and personal.”

While this project advances understanding of soil biodiversity, education is an important aspect of the work as well. More than 100 students participated in the first round of soil collection and research. Through hands-on sampling, data analysis, and interdisciplinary collaboration, students are gaining an understanding of the ways that ecology, climate, and human health intersect through soil, Hoffman said. The more microbial and bacterial genomes that are assembled, the greater the chance of discovering the next pathogen or the next cure is, she added. “At the end of the day, documenting soil biodiversity is not a problem that a single scientist can solve. We need a ton of people to do this.”

—Rebecca Owen (@beccapox.bsky.social), Science Writer

Citation: Owen, R. (2026), Nationwide soil microbiome mapping project connects students and scientists, Eos, 107, https://doi.org/10.1029/2026EO260046. Published on 3 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: Journal of Geophysical Research: Solid Earth

The deformation of Earth materials can occur either in a “brittle” manner, mediated by fractures whose propagation radiates elastic waves, or through “intracrystalline plasticity,” governed by the motion of crystalline defects and generally considered to be largely aseismic. However, within the “brittle–plastic transition,” these mechanisms are expected to coexist. Moreover, if intracrystalline defect propagation is sufficiently rapid and accompanied by stress release, it may also theoretically generate elastic waves.

O’ Ghaffari et al. [2026] present the first experiments in which optical, mechanical, and acoustic measurements are acquired simultaneously during the propagation of intracrystalline defects (twin boundaries) in calcite single crystals. High-speed imaging, reaching up to 12,500 frames per second, is combined with multiple ultrasonic sensors sampling up to 50 million samples per second, allowing deformation processes to be resolved across a wide range of spatial and temporal scales.

The experiments capture the evolution of both brittle microcracks and crystal-plastic twins as they propagate through the crystal. Direct comparison of image sequences and acoustic records demonstrates that these two deformation mechanisms generate distinct ultrasonic signals. In particular, subtle differences in waveform characteristics are linked to the physical nature of the defect source. This distinction provides a new basis for separating brittle and plastic deformation signals in acoustic emission data. The results have important implications for laboratory studies and for interpreting acoustic monitoring data in geological and other semi-brittle materials.

Citation: O’ Ghaffari, H., Peč, M., Cross, A. J., Mittal, T., & Mok, U. (2026). Brittle and crystal-plastic defect dynamics of calcite single crystals. Journal of Geophysical Research: Solid Earth, 131, e2025JB032846. https://doi.org/10.1029/2025JB032846

—Marie Violay, Associate Editor, JGR: Solid Earth

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.

An unusual failure has occurred on a cut slope adjacent to a key road in Greece.

On 2 February 2026 a major, fascinating landslide occurred on the A5 Ionian motorway between Arta and Amfilochia in Greece. The location appears to be [39.07754, 21.09861]. The news site ekathimerini has a story providing the details, which includes this extraordinary image of the aftermath of the landslide:-

The 2 February 2026 landslide on the Ionian motorway in Greece. Image from ERT via ekathimerini.

I believe that the Google Earth image below shows the configuration of the site in 2023:-

Google Earth image showing the site of the 2 February 2026 landslide on the Ionian motorway in Greece.

So, this is a large cut slope that appears to have been formed in about 2015 (based on Google Earth imagery). The failure is quite complex, with most of the landslide moving as a large block (which has fractured in the late stage of movement). There is a large displacement on the far side of the landslide (in the photograph view), so there has been some rotation around an approximately vertical axis. The landslide does not appear to have been conventionally rotational.

To me, this suggests failure on an existing plane of weakness in the slope. The news report indicate that the landslide occurred after heavy rainfall.

This is a Google Streetview of the landslide site from September 2023:-

Google Streetview image showing the site of the 2 February 2026 landslide on the Ionian motorway in Greece.

It appears that the slope has rockbolts, which suggests that there was an awareness of the potential for instability. Perhaps they were insufficiently long to prevent this failure? The presence of the rockbolts may explain why the landslide moved as a predominantly intact block, though.

The Ionian motorway is now closed. There are similar slopes along the road, so the investigation of this failure may have wider implications.

Return to The Landslide Blog homepage 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.

An agreement on the third implementation phase of Destination Earth (DestinE), the European Commission's initiative to develop a highly accurate digital twin of Earth, has been signed between the European Commission and the European Centre for Medium-Range Weather Forecasts (ECMWF). The third phase will start in June 2026 and end in June 2028.

When extreme weather strikes, the preparations of emergency planners can have life-or-death consequences. In July 2025, central Texas flooded with disastrous consequences, killing more than 130 people.

SummaryLandslide disasters are typically triggered by various environmental factors, making it crucial to understand the interaction between subtle internal changes and these factors for accurate risk assessment. Noise-based velocity change measurement offers a promising tool, yet its widespread application is limited by the inherent instability of noise sources, constraining temporal resolution. Here, we employ an wave-packet-based nine-component spatial stacking approach with a dense seismic array deployed at the Xishan Village landslide. This advancement allows for the extraction of extraction of high temporal velocity change (20-minute) at different frequencies, enabling four-dimensional dynamic analysis of landslide internal changes. Our findings reveal complex spatial distributions of velocity changes influenced by solar thermal radiation and rainfall at different locations and depths. Notably, during rainfall of approximately 20 mm, the observed maximum velocity reduction correlates closely with a fracture zone at ∼8 m depth, suggesting that pre-existing deformation structures significantly enhance local permeability, and promote the now deeper rainwater infiltration. This infiltration leads to increased pore pressure and velocity reduction. These results highlight the ambient noise method potential for urban landslide monitoring, providing technical support for early warning and risk assessment.

A study on tectonic plates that converge on the Tibetan Plateau has shown that Earth's fault lines are far weaker and the continents are less rigid than scientists previously thought. This finding is based on ground-monitoring satellite data. The study, published in Science, includes several high-resolution maps based on data from Copernicus Sentinel-1 satellites. It shows how the region is being stretched and squeezed by Earth's geological movements.

A research team from University of Tsukuba and collaborating institutions has clarified why M9-class megathrust earthquakes recur off the Kamchatka Peninsula with an unusually short cycle of 73 years. By analyzing the rupture process of the 2025 event, the team demonstrated that this earthquake exhibited complex behavior that cannot be explained by conventional seismic-cycle models.

In recent years, numerous landslides on hillsides in urban and rural areas have underscored that understanding and predicting these phenomena is more than an academic curiosity—it is a human necessity. When unstable slopes give way after intense rainfall, the consequences can be devastating, with both human and material losses. These recurring tragedies led us to a simple yet powerful question: Can we build landslide susceptibility maps that are more objective, transparent, and useful for local authorities and residents?

A study in Nature Geoscience reveals that changes in the West Antarctic Ice Sheet (WAIS) closely tracked marine algae growth in the Southern Ocean over previous glacial cycles, but not in the way scientists expected. The key factor is iron-rich sediments transported by icebergs from West Antarctica.

Water vapor (H2Ov) is an essential component of Earth's atmosphere, playing critical roles in climate regulation, weather patterns, and the water cycle. Its sources primarily come from natural processes such as ocean evaporation and terrestrial evapotranspiration. However, during the fossil fuels (e.g., coal, petroleum, natural gas) combustion process, in addition to emitting substantial amounts of CO2, they also generate significant amounts of water vapor as a byproduct (combustion-derived water vapor sources: CDWV).

An ongoing string of more than a dozen earthquakes in less than 90 minutes early Monday ended what had been some recent calm from recent weeks of shaking ground in the region, according to the U.S. Geological Survey.

A study by the Institut Català de Paleontologia Miquel Crusafont (ICP-CERCA) with the involvement of the UAB indicates that between 12.5 and 9 million years ago, in the Vallès-Penedès basin, rainfall was twice as high as it is today, and the climate was subtropical. The research has reconstructed the precipitation and climatic conditions of the past from fossils of small mammals found throughout the area. The research is published in the Journal of Mammalian Evolution.

A research team from the Aerospace Information Research Institute of the Chinese Academy of Sciences (AIRCAS) has developed a new method combining deep learning with physical radiative transfer modeling to improve the retrieval of atmospheric aerosol properties from complex satellite observations, supporting high-resolution, near-real-time monitoring of haze and dust events. The study was recently published in Journal of Remote Sensing.

Some tropical land regions may warm more dramatically than previously predicted, as climate change progresses, according to a new CU Boulder study that looks millions of years into Earth's past. Using lake sediments from the Colombian Andes, researchers reveal that when the planet warmed millions of years ago under carbon dioxide levels similar to today's, tropical land heated up nearly twice as much as the ocean.

A research group has revealed through seismic wave analysis that the oceanic plate beneath the Ontong Java Plateau—the world's largest oceanic plateau—was extensively altered by massive volcanic activity during its formation. The study is published in Geophysical Research Letters.

Dalhousie researchers have revealed how Arctic aquifers—permeable layers of the ground that store and transmit water to rivers, lakes and terrestrial ecosystems—behave today and how these vital resources will change with warming temperatures and sea-level rise.

Earth's ocean absorbs carbon dioxide from the atmosphere, helping to temper the impact of climate change but increasing ocean acidity. However, calcium carbonate minerals found in the seabed act as a natural antacid: Higher acidity causes calcium carbonate to dissolve and generate carbonate molecules that can neutralize the acid.