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SummaryThe joint use of data from GRACE-like gravity missions and various ocean altimetry missions in a global inversion approach allows to quantify the individual contributions to global and regional sea level budgets. However, the contribution from the Antarctic Ice Sheet (AIS) is subject to large uncertainties mainly depending on the applied strategy to account for effects due to glacial isostatic adjustment (GIA). The large uncertainty of GIA affects estimates of AIS contributions as well as other elements of sea level budgets. Here, we investigate strategies to improve the representation of AIS mass changes within an existing global inversion framework. The framework employs pre-defined, time-invariant spatial patterns, so-called fingerprints, for representing the individual sea-level budget components, including AIS contributions. We improve this inversion method by including additional observations of satellite altimetry over ice sheets, and by further developing the parameterization of AIS ice mass changes. We extend from a basin-wise spatial resolution to a parameterization that resolves time-variable ice mass changes at about 50 km, enabling a better localization of the AIS contributions to global and regional sea level change. From real-data experiments, we obtain ice mass balance estimates that are well within the uncertainty bounds of published reconciled estimates utilizing similar datasets. In particular, inclusion of ice altimetry improves the spatial resolution and at the same time keeps the global inversion results in line with those from regional GRACE analyses. We find differences between inversion results with and without including ice altimetry as an additional observation. These differences are smaller for the time period after 2010 with the availability of CryoSat-2 altimetry having improved sensor technology and high-latitude coverage. This indicates that these differences are caused by ice altimetry errors, whose further characterization and consideration within the estimation remains a future task. Furthermore, the spatial distribution of the differences suggests that they are also related to GIA errors. The improved representation of ice sheets in the global framework developed here provides a prerequisite for working towards minimizing GIA-related errors while assessing the ice sheets’ mass balance.

SummaryGiven the scarcity of seismometers in marine environments, traditional seismology has limited effectiveness in oceanic regions. Submarine Distributed Acoustic Sensing (DAS) systems offer a promising alternative for seismic monitoring in these areas. However, the existing machine learning model trained on land-based DAS data does not perform well with submarine DAS due to differences in noise characteristics, deployment conditions, and environmental factors. This study presents a machine learning approach tailored specifically to submarine DAS data to enable automated seismic event detection and P and S wave identification. Leveraging DeepLab v3, a neural network architecture optimized for semantic segmentation, we developed a specialized model to handle the unique challenges of submarine DAS data. Our model was trained and validated on a dataset comprising nearly 57 million manually and semi-automatically labeled seismic records from multiple globally distributed submarine sites, providing a robust basis for accurate seismic detection. The model adapts to a variety of deployment scenarios and can process DAS data from cables with different lengths, configurations, and channel spacings, making it versatile for various ocean environments. We thus provide an adaptable and efficient tool for automated earthquake analysis of DAS data, which has the potential to enhance real-time earthquake monitoring and tsunami early warning in submarine environments.

Africa's coastlines are under growing threat as sea levels climb faster than ever, driven by decades of global warming caused by human activity, natural climate cycles, and warming ocean waters. Between 2009 and 2024, the continent experienced a 73% increase in sea-level rise, according to a recent study published in Communications Earth & Environment.

A new study involving researchers from Oxford's Department of Earth Sciences has finally solved the mystery of what caused the collapse of an Ancient Chinese civilization—finding that widespread flooding was to blame. The findings have been published in National Science Reviews.

Publication date: 1 February 2026

Source: Advances in Space Research, Volume 77, Issue 3

Author(s): Somaiyeh Sabri, Stefaan Poedts

Publication date: 1 February 2026

Source: Advances in Space Research, Volume 77, Issue 3

Author(s): Ayşe Yadikar Habalı, Volkan Bakış

Using advanced computer simulations, researchers from the University of Rhode Island's Graduate School of Oceanography (GSO) have concluded how and why strong ocean currents modify surface waves. "Our primary finding is that hurricane-generated ocean currents can substantially reduce both the height and the dominant period of hurricane waves," said Isaac Ginis, URI professor of oceanography. "The magnitude of wave reduction depends strongly on how accurately ocean currents are predicted. This highlights the importance of using fully coupled wave-ocean models when forecasting hurricane waves."

The western U.S. is a geologists' dream, home to the Rocky Mountains, the Grand Canyon, active volcanoes and striking sandstone arches. But one landform simply doesn't make sense.

Hybrid climate modeling has emerged as an effective way to reduce the computational costs associated with cloud-resolving models while retaining their accuracy. The approach retains physics-based models to simulate large-scale atmospheric dynamics, while harnessing deep learning to emulate cloud and convection processes that are too small to be resolved directly. In practice, however, many hybrid AI-physics models are unreliable. When simulations extend over months or years, small errors can accumulate and cause the model to become unstable.

With the departure of the research vessel Polarstern from Punta Arenas (Chile) scheduled for this weekend, the "Summer Weddell Sea Outflow Study" (SWOS) international expedition will commence. Up to early April, a multidisciplinary international research team will investigate the northwestern region of the Weddell Sea—an area of central importance for the global climate and ocean system, but one that can only be explored on site by research icebreakers such as Polarstern due to challenging sea ice conditions.

When and how quickly can ecosystems "tip" and how will they develop in the future? Researchers from the University of Potsdam, the Potsdam Institute for Climate Impact Research, and the Technical University of Munich have developed a new method for measuring how close an ecosystem is to a catastrophic tipping point. They are applying their findings to predict glacier surges, as well as rapid changes in other ecosystems. They have now published their study in Nature Communications.

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

Students who have applied for the Graduate Research Fellowship Program (GRFP) from the National Science Foundation (NSF) have had their applications returned without review—even though their proposed research appears to fall squarely within the fields of study outlined in the program solicitation.

In response, a group of scientists created a template letter for students to share concerns with their representatives.

GRFP provides 3 years of financial support over a 5-year fellowship program for outstanding graduate students pursuing full-time degrees in science, technology, engineering, or math (STEM), including STEM education. The program solicitation, posted in September 2025, lists the following fields as eligible.

1. Chemistry
2. Computer and Information Sciences and Engineering
3. Engineering
4. Geosciences
5. Life Sciences
6. Materials Research
7. Mathematical Sciences
8. Physics & Astronomy
9. Psychology
10. Social, Behavioral, and Economic Sciences
11. STEM Education and Learning Research

However, at least dozens of applicants in those fields have received emails, obtained by Eos, that stated that their proposals were ineligible.

 Related

•  Thread in the GRFP subreddit
•  Grant Witness Template for Letter to Representatives
•  Get Involved: AGU Science Policy Action Center

 

“The proposed research does not meet NSF GRFP eligibility requirements. Applicants must select research in eligible STEM or STEM education fields,” the email read.

Neuroscience, physiology, ecology/biogeochemistry, and chemistry of life sciences are among the proposal research topics that have been returned without review (RWR), according to posts on Reddit and Bluesky.

One Redditor described the RWR as “soul-crushing.” “The dropdown menu part is what gets me,” they wrote, referring to how they selected a category from a list within the application. “What do you mean I am ineligible in a category that YOU provided?!”

Karolina Heyduk, an ecologist and evolutionary biologist at the University of Connecticut, shared on Bluesky that one of her student’s applications was rejected. Heyduk told Eos over email that she has no idea why, as the research—on photosynthesis in bromeliads—was “clearly within stated fields that are eligible, and had no agriculture, health, or policy angles.”

“The GRFP is an opportunity for new scientists to propose their best ideas and get their first shot at external funding. While not everyone will be funded, there is some expectation of a fair and transparent review process, and that doesn’t seem to be happening this year. For new grad students, or those applying this year, the outright rejection without a clear reason is incredibly discouraging,” she told Eos.

Rejected Appeals

Some applicants have appealed the decision, after having advisers look over their applications, and have received responses, also obtained by Eos, affirming that the decision is final.

“As your application was thoroughly screened based on these eligibility criteria, the RWR determination will stand and there will be no further consideration of your application,” the email text read.

Last March, the New York Times compiled, via government memos, agency guidance, and other documents, a list of words that the Trump administration indicated should be avoided or limited. The list included “climate science,” “diversity,” “political,” and “women.”

On Reddit threads, applicants who received RWR are speculating over whether their applications may have been automatically rejected for the use of so-called banned words. One student used the word “underrepresented” in a personal statement, to reference a program to which they had previously been accepted. Others, applying for neuroscience fellowships that involved studies with rats, wondered whether the word “ethanol” had been flagged. Another said they had tried to avoid using banned words, but that it was “unavoidable.”

“My project is about bears and ‘black’ is a trigger word,” they wrote. “Insane.”

Reaching out to Representatives

The group behind the template letter for students includes Noam Ross, who is among the creators of Grant Witness, a project to track the termination of scientific grants under the Trump administration. The letter notes that, after NSF awarded significantly fewer GRFP awards than usual in the spring, it released its guidance for this year’s application more than a month later than usual—leaving students with much less time than usual to complete their applications, and leaving others ineligible to apply.

“I request that you contact the NSF administrator to ask why eligible GRFP applications are being rejected without review and to ask them to remedy the situation quickly, as review panels are convening imminently,” the letter reads. “We cannot allow the continued degradation of our scientific workforce, and [the cutting] off the opportunities for so many future scientists.”

—Emily Gardner (@emfurd.bsky.social), Associate Editor

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. 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.

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

The solar wind is a continuous stream of charged particles released from the Sun into the solar system. It plays a major role in space weather, which can impact satellites, astronauts, and power systems on Earth. Forecasting the solar wind often depends on detailed maps of the Sun’s magnetic field and complex models of the solar corona, which introduce uncertainty and are not always available.

Owens et al. [2026] present a new approach that uses solar wind measurements near Earth to reconstruct solar wind conditions closer to the Sun. By tracing the solar wind back towards its source, the method provides realistic starting conditions for solar wind models without relying on magnetic maps. The authors show that this approach can produce realistic solar wind conditions while reducing assumptions and sources of error. This simpler set-up allows the method to be applied consistently across different modelling frameworks.

This work represents an important step towards more robust and accessible solar wind modeling. In the long term, it can help improve space weather forecasts and our ability to protect technology and infrastructure in space and on Earth.

Citation: Owens, M. J., Barnard, L. A., Turner, H., Gyeltshen, D., Edward-Inatimi, N., O’Donoghue, J., et al. (2026). Driving dynamical inner-heliosphere models with in situ solar wind observations. Space Weather, 24, e2025SW004675. https://doi.org/10.1029/2025SW004675

—Tanja Amerstorfer, Associate Editor, Space Weather

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.

A UT San Antonio-led international research team has identified chitin, the primary organic component of modern crab shells and insect exoskeletons, in trilobite fossils more than 500 million years old, marking the first confirmed detection of the molecule in this extinct group.

Researchers at Kyoto University have proposed a new physical model that explores how disturbances in the ionosphere may exert electrostatic forces within Earth's crust and potentially contribute to the initiation of large earthquakes under specific conditions. The study does not aim to predict earthquakes but rather presents a theoretical mechanism describing how ionospheric charge variations—caused by intense solar activity such as solar flares—could interact with pre-existing fragile structures in Earth's crust and influence fracture processes.

Earth's surface is covered by more than a dozen tectonic plates, and in subduction zones around the world—including the Japanese Islands—plates converge and dense oceanic plates sink into Earth's interior. These regions, especially plate boundaries, are known for frequent seismic activity.

Southern California's beaches have grown more than 500 acres over the past four decades despite being one of the most heavily urbanized and dammed coastal regions in the world, according to a new study conducted by researchers at the University of California, Irvine, the U.S. Geological Survey and other institutions. The conventional wisdom-challenging revelation about coastal erosion and replenishment is the subject of the study published recently in Nature Communications.

Source: Journal of Geophysical Research: Biogeosciences

From 1948 to 1953, a gold mine called Giant Mine released about 5 tons of arsenic trioxide per day into the environment around Yellowknife, Northwest Territories, Canada. Emissions declined from the 1950s until the mine closed in 2004, but the surrounding landscape remains highly contaminated with arsenic.

Little et al. recently studied how the spring thaw influences arsenic levels in four Yellowknife area lakes and how phytoplankton populations alter arsenic biogeochemistry during this transition period. The researchers sampled each lake twice per year in 2022 and 2023: once in late April, before the beginning of the spring thaw period, and once 7–10 days later, when the thaw had begun but the ice was still thick enough to safely walk on, making sample collection feasible.

Sammy’s, Handle, Frame, and Jackfish lakes spanned a gradient of arsenic contamination levels when measured before the thaw in 2022—from 5.5 micrograms per liter in Sammy’s Lake to 350 micrograms per liter in Frame Lake. In Handle, Frame, and Jackfish lakes, arsenic levels went down as the spring thaw began, but Sammy’s Lake followed the opposite trend. The difference likely lies in how much arsenic the lakes contained to begin with. With Sammy’s Lake starting at such a low level, arsenic from meltwater exacerbated the contamination. In the other three lakes, the concentration of arsenic in meltwater was lower than or similar to the starting concentration in the lake, so meltwater diluted the contamination.

Arsenic exists mostly in two oxidation states: arsenite and the less toxic, less mobile arsenate. Because arsenate is more stable under oxic conditions, the influx of highly oxygenated snow and ice meltwater during the spring thaw period was accompanied by a predictable shift in the predominant form of arsenic in the lakes.

The winter of 2022 was significantly colder than 2023, with the difference reflected in the thickness of the ice: 76–130 centimeters in 2022 compared with 65–72 centimeters in 2023. The warm winter did not alter the final arsenic concentration or speciation in the water at the end of the thaw. However, an increase was observed in plankton communities in more mature life stages and in taxa that are more competitive in warmer conditions. This result is important, the authors say, because late winter and spring thaw plankton community dynamics set the stage for the following open-water season. (Journal of Geophysical Research: Biogeosciences, https://doi.org/10.1029/2025JG009231, 2026)

—Saima May Sidik (@saimamay.bsky.social), Science Writer

Citation: Sidik, S. M. (2026), How the spring thaw influences arsenic levels in lakes, Eos, 107, https://doi.org/10.1029/2026EO260051. Published on 6 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.

Until 1959, nobody on Earth had ever seen our Moon’s farside. Thanks to gravitational tidal forces, the lunar nearside always faces us, so it was surprising for everyone to learn that the other half of the Moon looks strikingly different. Not only that, but subsequent observations showed the lunar farside has a thicker surface than the nearside, and its rocks have different compositions.

And nobody knows exactly why.

However, some scientists think the solution to the mystery involves a site known as the South Pole–Aitken (SPA) basin, which was created by an asteroid impact early in the solar system’s history. A new study published in the Proceedings of the National Academy of Sciences of the United States of America draws from surface samples returned by the Chang’e-6 (pronounced CHAHNG-ua) robotic probe. The samples contain minuscule differences in chemical and isotopic composition that indicate the ancient impact may have vaporized part of the Moon’s interior, enough to account for the differences between the near- and farsides.

“Chang’e-6 currently provides the only samples returned from the lunar far side,” said planetary geochemist Heng-Ci Tian ( 田恒次) of the Institute of Geology and Geophysics at the Chinese Academy of Sciences, Beijing, in an email to Eos. Comparing these samples to those collected by previous Chang’e probes and the Apollo missions, Tian and his colleagues determined the impact did more than just make a big crater: It reshuffled the geological components of the lunar mantle. In particular, they looked at isotopes of moderately volatile substances such as potassium that vaporize at relatively low temperatures, rather than more abundant, low-mass elements like hydrogen and oxygen.

If this hypothesis holds up under further scrutiny, it would not only tell us about our Moon’s history and origins but help us understand planetary evolution in general.

As with Earth, the Moon’s mantle—the relatively plastic layer of minerals between the crust and core—is the source of the magma that once powered volcanoes. The nearside is marked by ancient volcanic flows, known as “mares” (pronounced MAR-ays) or “seas,” which are largely absent on the farside.

“Our study reveals that the SPA basin impact caused [evaporation] of moderately volatile elements in the lunar mantle,” Tian said. “The loss of these volatile elements likely suppressed magma generation and volcanic eruptions on the far side.”

If this hypothesis holds up under further scrutiny, it would not only tell us about our Moon’s history and origins but help us understand planetary evolution in general. After all, Earth’s surface is constantly renewed by plate tectonics and hydrologic processes, but other worlds such as Mars and Venus are less dynamic, and much of what is going on inside is still mysterious.

“There’s so many uncertainties as to really what happened [when SPA formed] and how it would’ve affected the interior,” said Kelsey Prissel, a planetary scientist at Purdue University in Indiana who was not involved in the study. She pointed out that different geophysical processes like crystallization and evaporation lead to different populations of isotopes. The new study, which shows a larger fraction of certain isotopes in the SPA region than on the lunar nearside, therefore provides strong evidence that the farside mantle was partially vaporized long ago.

“Previous studies have shown that impacts alter the composition and structure of the lunar surface and crust, but our study provides the first evidence that large impacts play an important role in planetary mantle evolution,” Tian said.

It Came from the Farside!

The SPA basin is one of the biggest impact craters in the solar system, so huge it doesn’t even look like a crater: It stretches all the way from the lunar South Pole to the Aitken crater (hence the name) at approximately 16°S latitude. Researchers determined it formed about 4.3 billion years ago—not long, in cosmic terms, after the Moon was born. Interestingly, it is also almost directly antipodal to a cluster of volcanoes on the lunar nearside, which suggested to some scientists the features might be related.

However, the farside is harder to study. Humanity’s first view came only in 1959 with the uncrewed Soviet Luna 3 orbiter, and none of the Apollo missions landed there. Robotic spacecraft have mapped the entire Moon in detail, but the Chang’e-4 probe achieved humanity’s first farside landing in 2019. Chang’e-6 landed in the SPA basin on 1 June 2024 and returned the first (and so far only) samples from the lunar farside to Earth on 25 June.

“[If] you looked at this data 20 years ago, [the samples] would all look the same.”

The next phase in the study was comparing the chemical makeup and isotopes in these rocks to their nearside counterparts collected by the Apollo astronauts and the Chang’e-5 mission. In particular, Tian and his colleagues looked at potassium (K), rare-earth elements, and phosphorous, collectively known as KREEP, which are possibly related to mantle composition. As the researchers noted in their paper, if the SPA impact vaporized materials in the Moon’s mantle, it might also have redistributed KREEP-rich minerals from the farside to the nearside. Testing this hypothesis required doing very sensitive laboratory measurements that weren’t possible in the Apollo era.

“Having the far side samples is brand-new no matter what,” Prissel said. “But looking at these really fine differences between isotopes is something we haven’t been able to do forever. [If] you looked at this data 20 years ago, [the samples] would all look the same.”

Prissel’s point highlights the interdependency of different branches of planetary science: Understanding the Moon’s interior requires studying samples, performing laboratory experiments on them (or on analog materials), and running theoretical models. These new results will inform the next set of experiments and modeling, as well as guide future lunar sample return missions.

“We plan to analyze additional volatile isotopes to verify our conclusions,” Tian said. “We will combine these with numerical modeling to further evaluate the global effects of the SPA impact.”

—Matthew R. Francis (@BowlerHatScience.org), Science Writer

Citation: Francis, M. R. (2026), Primordial impact may explain why the Moon is asymmetrical, Eos, 107, https://doi.org/10.1029/2026EO260050. Published on 6 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.

A new study led by Prof. Xiao Wenjiao from the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences sheds light on the ore-forming process and key mechanisms of the gold deposit in the South Tianshan of northwest China. The research was published in the Geological Society of America Bulletin on Jan. 20.