Feed aggregator

Source: Geophysical Research Letters

In magnetic reconnection, adjacent magnetic field lines break and snap together to form new lines. This process converts magnetic energy to both thermal energy, or heat, and kinetic energy, or the acceleration of particles, creating jets of electrons and ions. Magnetic reconnection plays a key role in many outer space events such as solar flares and aurorae, as well as in laboratory methods related to nuclear fusion.

Several years ago, observations of Earth’s magnetic field by NASA’s Magnetospheric Multiscale mission led to the discovery that magnetic reconnection can occur with only electron jets, without also involving the acceleration of ions. These events also have a relatively high reconnection rate, meaning the involved magnetic field lines snap together quickly. Now Fan et al. report the results of new simulations that deepen the understanding of these electron-only events.

The researchers applied a computational method known as particle-in-cell simulation to model the behavior of ions and electrons during magnetic reconnection. They ran 12 simulations to explore what factors might underlie electron-only reconnection.

The simulations revealed that the electron-only status of reconnection occurs when field lines outside of the electron diffusion region do not bend enough, leading to an underdeveloped ion diffusion region. This atypical bending happens in the early stage and may continue throughout the process if the entire system size (the size of the area in which reconnection occurs) is smaller than the radius of the path along which the ions travel.

The team also realized that magnetic reconnection and field line bending may not develop at the same pace. A relatively thin initial current sheet allows the reconnection rate to peak before field lines are fully bent, leading to calculations of high reconnection rates if they are normalized by ion parameters. However, the calculations of the reconnection rate are more typical when they are normalized by electron parameters.

These findings could help clarify the fundamental physics of magnetic reconnection, the authors suggest. (Geophysical Research Letters, https://doi.org/10.1029/2024GL113889, 2025)

—Sarah Stanley, Science Writer

Citation: Stanley, S. (2025), New insights into an enigmatic form of magnetic reconnection, Eos, 106, https://doi.org/10.1029/2025EO250138. Published on 11 April 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Cycles of ice sheet growth (glacials) and intervening warmth (interglacials) in Earth’s past—largely triggered by shifts in the amount of solar radiation (insolation) reaching the planet—have been characterized by major changes in global atmospheric carbon dioxide (CO2) levels, sea levels, and temperatures. Around the time of the Last Glacial Maximum 20,000 years ago, for example, average global temperatures were roughly 6°C (11°F) colder, and sea levels were more than 120 meters (400 feet) lower than today, whereas ice covered about a quarter of Earth’s land surface.

Such changes have had profound effects on ecosystems, particularly coastal ecosystems, including coral reefs. And as CO2 levels, temperatures, and sea levels rise rapidly around the world today, modern ecosystems—humans included—will likely continue to experience major impacts as well.

Coral reef systems are highly sensitive to sea level and climate, and fossil reefs preserve reliable records of past variations.

Yet many unknowns remain about the mechanisms that control climate transitions, particularly during past episodes of rapid warming. These unknowns raise critical questions about present and future warming as well: Are predictions of catastrophic sea level rise—up to several meters—resulting from ice sheet collapse valid? Will the behavior and effects of annual to interannual climate phenomena, such as the El Niño–Southern Oscillation and seasonal rainfall, change as the average global climate changes?

Also uncertain is how coral reefs and coasts will respond to associated environmental stresses. Coral reef systems are highly sensitive to sea level and climate, and fossil reefs preserve reliable records of past variations. Yet our understanding of these variations is severely limited because we lack continuous fossil coral records, particularly from periods of abrupt climate instability. Such records are exceptionally rare given the specific conditions required to build and preserve fossil reef sequences over extended periods and the difficulty of sampling them where they do occur.

In fall 2023, scientists and crew on the International Ocean Discovery Program’s (IODP) Expedition 389 (X389) employed an advanced, remotely operated seabed drilling system to access the interiors of submerged, or “drowned,” fossil reefs off the island of Hawai‘i for the first time (Figure 1). The reef sequences there contain globally unique records of sea level and climate change—and their impacts on reef ecosystems—over the past 500,000 years [Webster et al., 2025].

Fig. 1. A unique sequence of drowned fossil coral reefs was sampled off Hawai‘i during X389. (a) Sampling sites (red markers) are indicated along with their depths below sea level and name (H1, H2, etc.). (b) Sea level changes (blue curve) are shown through the cold glacials (blue shading) and warm interglacials (orange shading) over the past 600,000 years [Rohling et al., 2009; Elderfield et al., 2012; Lambeck et al., 2014]. New preliminary age data (red bars) confirm that reefs H1–H8 (gray bars) span 13 glacial-interglacial intervals (termed marine isotope stages (MIS), numbered boxes), including rapid climate transitions. ka = thousand years ago. Credit: Adapted from Webster et al. [2025], CC BY 4.0 Hawai‘i’s Unique Reef Records

Hawai‘i is geologically special. Located over an active volcanic hot spot, it has been—and continues to be—built up by successive eruptions. As the underlying mantle compensates for the increasing weight of the island, the ocean crust has experienced nearly constant subsidence over the past 500,000 years. This subsidence creates space that accommodates growth and vertical expansions of reefs, which, as they accumulate and fossilize, capture conditions through glacial-interglacial intervals in great detail (Figures 1b and 2). These reefs ring the island, forming a spectacular sequence of increasingly older terraces between 100 and 1,500 meters below present sea level (Figure 1a).

Rapid sea level rises linked to catastrophic ice sheet collapse and abrupt meltwater pulse events during deglaciations cause reef drowning.

The reefs have been the subject of 4 decades of data collection and study involving multiple methods of seafloor imaging (bathymetric, backscatter, and seismic) and sampling (with dredges, submersibles, and remotely operated vehicles), as well as geochronologic methods and numerical modeling [Webster et al., 2009]. These prior data underpin our knowledge of fossil reef development and motivated the scientific rationale and drilling strategy of X389.

As Hawai‘i subsides at a rate of 2.5 millimeters per year, space below the ocean surface is created for reef growth in the near term (Figure 2). But how do large and longer-term sea level changes occurring through glacial-interglacial intervals affect reefs?

Reef growth initiates during sea level highstands and continues during glaciation as sea levels slowly drop. If sea level falls quickly, outpacing the island’s subsidence rate, the living part of the reef dies as it is exposed above the waves. If, on the other hand, sea level rises too quickly and new reef growth—which requires the sunlight available near the ocean surface—fails to keep up, the reef will deepen and ultimately drown.

Fig. 2. This conceptual model illustrates the development and accumulation of drowned fossil coral reefs and other rock facies (e.g., microbialites, volcanic deposits) in different paleoenvironments around Hawai‘i over the past 100,000 years in response to rapid island subsidence, which creates accommodation space (double-headed arrow), and changing sea levels (dark blue curve). ka = thousand years ago; mbsl = meters below sea level. Credit: Adapted from Webster et al. [2025], CC BY 4.0

Rapid sea level rises linked to catastrophic ice sheet collapse and abrupt meltwater pulse events during deglaciations thus cause reef drowning [Sanborn et al., 2017]. Then, during the subsequent warm high sea level stand, a new reef is initiated upslope, and the cycle starts again.

Numerical models of reef growth and demise, forced by changes in sea level, predict that the Hawaiian terraces comprise thicker sequences of fossilized reef—100–150 meters per glacial cycle—compared with those built on stable margins such as the Great Barrier Reef. As such, the Hawaiian expanded sequences hold great promise for providing sea level and climate records of unprecedented resolution and detail.

To sample these Hawaiian reefs across a range of water depths and challenging lithologies (they commonly fragment and break), researchers required a novel drilling system—unavailable to the scientific community until recently—that could penetrate the reef interior rather than just scratch its surface.

The Core of the Matter

The X389 team found the needed technology in Benthic’s fifth-generation portable remotely operated drill (PROD5). This commercial, tethered device can be guided to and secured at seafloor targets as deep as several kilometers, where its automated capabilities allow it to collect long sample cores (up to 73 meters below the seafloor in the case of X389). A major advantage of seafloor drills over ship-based systems is that they’re stationary, which makes it easier to keep constant weight on the drill bit and improves recovery of continuous core segments.

Scenes from X389’s drilling operations show the PROD5 drill (a) being deployed over the side of the MMA Valour and (b) landing on the seafloor, as well as (c) team members processing and archiving a core collected from a well-preserved fossilized massive Porites coral. Credit: Jody Webster

Sailing aboard the MMA Valour, the expedition used PROD5 to obtain reef material from roughly the past 500,000 years to address four major objectives: (1) measuring the extents of past sea level variations, (2) investigating seasonal to millennial climate and oceanic change, (3) assessing coral reef ecosystem responses to abrupt sea level and climate changes, and (4) improving knowledge of the growth and subsidence of Hawai‘i over time.

Over the course of 2 months in fall 2023, we deployed the drill at 16 drowned reef sites offshore Hawai‘i, coring 35 holes at water depths ranging from 132 to 1,242 meters (Figure 1a). A total of 425 meters of core were recovered, comprising both reef (83%) and volcanic (17%) materials. Core recoveries averaged 66%, and numerous intervals of well-preserved reef samples exhibited recoveries greater than 90%, significant achievements compared with recoveries from prior expeditions. For example, core recoveries averaged 27% using a ship-based drilling system during Expedition 325 to the Great Barrier Reef in 2010 [Webster et al., 2011].

The deployments were largely successful, but the expedition was not all smooth sailing.

The deployments were largely successful, but the expedition was not all smooth sailing. Technical issues with the drill, including mechanical breakdowns and difficulties penetrating heterogeneous coral reef material, limited our ability to reach all target depths.

Moreover, the expedition did not adequately engage with community members about the plans and purpose of its research or about concerns it may have posed. This regrettable oversight alienated members of the local and Native Hawaiian communities, some of whom expressed frustration at not being informed or consulted prior to the Valour’s arrival offshore and voiced uncertainties over possible environmental harms.

In addition to damaging the expedition’s relationship with local communities, the lack of timely and vital engagement directly affected the science we could pursue. The concerns raised by community members contributed to the denial of a permit to drill in state waters—a decision received after X389 was already at sea—meaning that we could not sample at some young, science-critical reef sites as originally planned.

Consequently, we pivoted our approach to add more sites in federal waters where we could sample other young reef sequences and to drill transects of shorter, but high-quality, cores to capture small sea level oscillations. Since the research cruise, expedition members have sought to redouble community engagement efforts to redress the offenses and concerns caused by the expedition.

Ancient Anatomy Lessons Fig. 3. Line scan images of two core sections show shallow, in situ reef frameworks characterized by branching Porites coral with well-developed encrusting coralline algae, vermetid gastropods, and microbialite deposits. These cores were collected from the same H2 reef terrace but on opposite sides of Hawai‘i, (a) one near Kawaihae on the leeward, dry side and (b) one near Hilo on the windward, wet side; they are indicative of rapid reef accretion in response to sea level rise and differing riverine inputs. Credit: Adapted from Webster et al. [2025], CC BY 4.0

Analysis of the hundreds of meters of core collected during X389 will reveal, for the first time, the complex internal anatomy and composition of Hawai‘i’s extensive reef packages through the past half million years. Preliminary visual observations have already offered glimpses of exquisite new details, including drowning reef sequences formed during the terminations of glacial periods [Webster et al., 2025]. The building blocks of these drowning reefs include branching, columnar, and massive shallow corals; several types of microbialite; thick crustose coralline algae (Figure 3); lithified and unlithified sediments; and a diversity of volcanic flows and associated sediments.

Observations so far also suggest that our sampling captured distinct shallow, intermediate, and deep reef communities and depositional settings, as well as the first evidence of major lithologic boundaries indicating repeated reef initiation and demise, as predicted by models and previous seafloor observations [Webster et al., 2009] (Figure 2). Furthermore, substantial differences in sedimentary contributions to the reefs between the dry and wet sides of Hawai‘i highlight that variations in precipitation, sediments, and nutrient input might influence reef evolution (Figure 3).

Fig. 4. A suite of nondestructive analytical techniques from across the electromagnetic spectrum was used to investigate fossil coral reef cores collected during X389. Shown here are representative high-resolution images of a robust branching Porites coral and other components from the same core from the H2 reef terrace (dated to between MIS7 and MIS6). The images include (a) a line scan image, (b) an X-ray computed tomography image showing 3D density changes, and hyperspectral images providing mineralogic information such as the (c) aragonite index, (d) calcite index, and (e) minimum wavelength mapping. Credit: Adapted from Webster et al. [2025], CC BY 4.0

Early analyses of the cores have been done using a suite of nondestructive imaging techniques (Figure 4). X-ray computed tomography is providing 3D reconstructions of massive Porites coral specimens, which often provide accurate records of past ocean conditions. In addition, traditional high-resolution line scans integrated with high-resolution hyperspectral scanning of the cores are revealing carbonate and other minerals (e.g., aragonite, calcite, clay, and iron), helping to guide sampling and more detailed analyses of the cores.

Windows into the Past and Future

The material recovered during X389 is between 10,000 and 500,000 years old and includes hundreds of well-preserved samples. These samples will be used to reconstruct the first absolute dating of sea level changes during portions of this time window. Putting absolute dates to these changes will have profound implications for testing theories about the drivers and triggers of past glacial-interglacial cycles and for validating climate and ice sheet models that are critically important for predicting sea level changes resulting from current and future global warming.

Further, the X389 cores include more than 300 Porites coral specimens with annual banding that will provide the first estimates of seasonal to millennial paleoclimate variability in the region. Geochemical analyses can be used to estimate monthly oceanographic variability with respect to temperature, precipitation, nutrient dynamics, carbon chemistry, and pH.

Assessing the nature of variability at different temporal scales will help answer critical questions. For example, were the occurrence and seasonality of extreme climate events in the past dependent on the background average climate state at times when global temperature, Pacific storm tracks positions, solar insolation, and atmospheric CO2 levels were different? The state dependency of high-frequency temperature and hydroclimate variability is a key question today as Earth warms.

The sequences of reef lithologies recovered during X389, including volcanic flows and the diverse variety and shapes of reef-building organisms, will be interpreted to reveal a story of ecosystem response to geological processes and paleoclimatic variations in sea level and oceanographic conditions. This interpretation will inform broader understanding of the factors that control reef growth, reef health, and coastal resilience in subsiding island settings in the face of future changes in hydroclimate, ocean temperature, nutrient availability, sediment supply, and ocean pH.

The X389 science party is working together to continue studying the collected cores in greater detail to address the project’s scientific goals. And we welcome contributions from external scientists as well: Careful sampling of the cores has left much of the material intact, and as of late February 2025, anyone can request X389 samples from the IODP core repository at Texas A&M University. With concerted and collaborative efforts, we can continue the flexible and inclusive approach of IODP—even as the Sun sets over its current phase—to advance knowledge of the paleoclimate over the past 500,000 years and understanding of what conditions Earth may experience in the future.

Acknowledgments

We thank the entire IODP 389 Expedition Science Party, ECORD Science Operator (ESO) support staff, Benthic drilling team, MMA surveyors, and the captain and crew of the MMA Valour for their outstanding work on the offshore and onshore phases of the expedition. IODP Expedition 389 was supported by funding from the various national funding agencies of the participating IODP countries.

References

Elderfield, H., et al. (2012), Evolution of ocean temperature and ice volume through the mid-Pleistocene climate transition, Science, 337(6095), 704–709, https://doi.org/10.1126/science.1221294.

Lambeck, K., et al. (2014), Sea level and global ice volumes from the Last Glacial Maximum to the Holocene, Proc. Natl. Acad. Sci U. S. A., 111(43) 15,296–15,303, https://doi.org/10.1073/pnas.1411762111.

Rohling, E. J., et al. (2009), Antarctic temperature and global sea level closely coupled over the past five glacial cycles, Nat. Geosci., 2(7), 500–504, https://doi.org/10.1038/ngeo557.

Sanborn, K. L., et al. (2017), New evidence of Hawaiian coral reef drowning in response to meltwater pulse-1A, Quat. Sci. Rev., 175, 60–72, https://doi.org/10.1016/j.quascirev.2017.08.022.

Webster, J. M., et al. (2009), Coral reef evolution on rapidly subsiding margins, Global Planet. Change, 66(1–2), 129–148, https://doi.org/10.1016/j.gloplacha.2008.07.010.

Webster, J. M., et al. (2011), Great Barrier Reef environmental changes, Proc. Integrated Ocean Drill. Program, 325, https://doi.org/10.2204/iodp.proc.325.2011.

Webster, J. M., et al. (2025), Hawaiian drowned reefs, Proc. Int. Ocean Discovery Program, 389, https://doi.org/10.14379/iodp.proc.389.2025.

Author Information

Jody M. Webster (jody.webster@sydney.edu.au), School of Geosciences, Geocoastal Research Group, University of Sydney, Australia; and Christina Ravelo (acr@ucsc.edu), Ocean Sciences Department, Institute of Marine Sciences, University of California, Santa Cruz

Citation: Webster, J. M., and C. Ravelo (2025), Unlocking climate secrets of Hawai‘i’s drowned reefs, Eos, 106, https://doi.org/10.1029/2025EO250135. Published on 11 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Past lunar missions have detected evidence of large ice deposits in permanently shadowed regions near the Moon’s south pole. Such ice could provide astronauts with drinking water, oxygen, and rocket propellants, reducing the cost of lunar operations.

But new research has found that astronauts might not have to dig very deep or journey especially close to the Moon’s poles to find water ice. A recent study published in Communications Earth and Environment says the critical resource for future lunar explorers might lurk tantalizingly close to the surface on pole-facing slopes at lower latitudes. The Sun shines at a low angle on such regions, which may allow ice to accumulate just centimeters below the surface, where it would be insulated by lunar regolith.

The Moon’s low axial tilt means that craters and low-lying areas near the south pole never see direct sunlight. This lack of sunlight would allow even surface ice deposits to remain frozen for a long time—perhaps billions of years. Because of the likely presence of ice, both NASA and China’s space agency have announced plans to land astronauts near the south pole and eventually establish permanent outposts there.

The Chandrayaan-2 orbiter photographed the Vikram lander from orbit. Credit: Indian Space Research Organisation

Locations farther from the poles “can also become potential locations for future human habitats, with better illumination and smoother topography than the poles. These regions pose less technical challenges for landing and operations.”

“Our study reveals that the poles are not the only options for future exploration,” said K. Durga Prasad, lead author of the report and a planetary scientist at the Physical Research Laboratory in Ahmedabad, India. Locations farther from the poles “can also become potential locations for future human habitats, with better illumination and smoother topography than the poles. These regions pose less technical challenges for landing and operations.”

“This result is very much consistent with both theoretical modeling studies and observations made by Lunar Reconnaissance Orbiter,” said Timothy McClanahan, an emeritus planetary scientist at NASA’s Goddard Space Flight Center who was not involved with the study.

First Measurements Since Apollo

The new lunar temperature data come from Chandra’s Surface Thermophysical Experiment (ChaSTE), an instrument aboard the Vikram lander, which itself was part of India’s Chandrayaan-3 mission. Vikram touched down on 23 August 2023 at 69° south latitude, the most southerly landing site at that time. (Two subsequent landers, both built by the American company Intuitive Machines, landed farther south, but both tipped over on landing and were unable to achieve all of their science goals.)

ChaSTE collected data continuously from 24 August to 2 September, shortly before the Sun set on the solar-powered lander (a lunar day lasts about 29.5 Earth days). The probe penetrated 10 centimeters into the regolith, with temperature sensors spaced at 1-centimeter intervals. The instrument also heated the regolith to measure its thermal conductivity.

ChaSTE provided the first direct subsurface lunar temperature measurements since the Apollo 15 and 17 missions of the early 1970s. The Apollo heat probes drilled deeper than ChaSTE did but provided fewer measurements of the top 10 centimeters. The Apollo sites also were close to the equator, where temperatures are likely to remain too warm for water ice even well below the surface, Prasad said.

An enlarged version of the Pragyan image of Vikram indicates the location of the ChaSTE instrument, which measured thermal conductivity and temperatures, and the Instrument for Lunar Seismic Activity (ILSA). Credit: Indian Space Research Organisation

Vikram landed on the rim of a shallow crater in a Sun-facing area with a 6° slope. ChaSTE and other instruments aboard the lander recorded a peak daytime surface temperature of 355 K (81.85°C). That was higher than expected on the basis of both models and observations by Diviner, an infrared instrument aboard the Lunar Reconnaissance Orbiter that has compiled temperature maps of much of the lunar surface. (Temperatures at the probe’s maximum depth ranged from 55 K to 85 K colder than surface temperatures, depending on the time of day.)

However, the temperature on a flat area just 1 meter from the ChaSTE site peaked at only 332 K (58.85°C), suggesting that a location’s slope could play a significant role in its subsurface temperatures.

The findings “validated the idea that topographic variation, even toward meter scales, has an important impact on locations where we might expect water ice to occur,” McClanahan said.

Taking the Right Angle

Modeling showed that at high latitudes, poleward-angled slopes of 14° or greater could remain cold enough to preserve ice at depths of just a few centimeters. The Sun would hit such tilted regions at a low angle, minimizing heating, and the fine-grained top layer of the regolith would be an efficient thermal blanket, effectively insulating the shallow subsurface.

“Depending on the slope, you can have a lot of temperature variation even in craters as small as a meter. One side might be quite warm, but…you could have conditions that are suitable for water ice on the poleward-facing slope.”

“Depending on the slope, you can have a lot of temperature variation even in craters as small as a meter,” McClanahan said. “One side might be quite warm, but given the low thermal conductivity of the regolith, you could have conditions that are suitable for water ice on the poleward-facing slope.” The slope angle suitable for hosting ice increases as you move farther from the pole, he added.

The Vikram team is continuing to analyze the ChaSTE observations to learn more about the thermal characteristics of the landing site and of high lunar latitudes in general, Prasad said. In addition, because temperatures are important for any lunar lander, “future missions will definitely carry similar instruments that will also help substantiate our results,” he said.

—Damond Benningfield, Science Writer

Citation: Benningfield, D. (2025), Lunar ice might be easier to reach than we thought, Eos, 106, https://doi.org/10.1029/2025EO250136. Published on 11 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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

Magma transport involves interactions of rocks and volatiles in their solid, fluid, and gas phases that must be captured by physical models across a vast range of scales. What complicates matters further is that eruptions respond to heterogeneous and time-variable source conditions modulated by a crust that experiences hysteresis due to its volcano-tectonic history. Any efforts of interpreting signals such as the multi-decadal unrest at the Campi Flegrei, Italy volcanic fields thus must find the balance between honoring the regional specifics and fundamental volcano dynamics.

Numerical scenario computation illustrating how dike populations may respond to the large-scale caldera stress field. Credit: Buono et al. [2025], Figure 7l

Buono et al. [2025] present a sweeping review that seeks to integrate rock physics, seismic tomography, and mechanical modeling into a systems-level understanding of the Campi Flegrei setting. It appears that the combination of caldera geometry and lithology leads to a crustal stress state that affects volcanic dike ascent which in turn may feed back into crustal deformation behavior. This suggests the importance of a resulting weak crustal layer for subsequent magma and gas pathways and perhaps an evolutionary scenario for similar volcanic centers. While the modeling is suggestive, there are a range of interactions and features left to be explored. However, the range of geophysical and geological constraints that are accessible in well instrumented volcanic systems points toward the potential of future, fully integrated models that might be capable of assimilating time dependent observations for improved, physics-based forecasting of volcanic hazards.

Citation: Buono, G., Maccaferri, F., Pappalardo, L., Tramelli, A., Caliro, S., Chiodini, G., et al. (2025). Weak crust owing past magmatic intrusions beneath Campi Flegrei identified: The engine for bradyseismic movements? AGU Advances, 6, e2024AV001611. https://doi.org/10.1029/2024AV001611

—Thorsten Becker, Editor, AGU Advances

Text © 2024. 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.

Research led by the Union of Concerned Scientists reports that emissions from the world's largest fossil fuel and cement companies have contributed significantly to both present-day and long-term sea level rise. Products from 122 major producers have contributed up to 37% of the rise in global sea level observed through 2022 and may account for an additional 0.26 to 0.55 meters by 2300.

Author(s): Travis Garrett, Anna Janicek, J. Todd Fayard, II, and Jennifer Elle

Ultrashort pulsed lasers can produce thin columns of plasma in the air via femtosecond filamentation, and these plasmas have been found to generate broadband terahertz and radio frequency (RF) radiation. A recent theory argues that the currents driven at the boundary of the plasma excite a surface p…

[Phys. Rev. E 111, 045206] Published Fri Apr 11, 2025

Author(s): R. Sarkis, N. Dumerat, B. Schmid, G. E. M. Tovar, and M. Ramisch

The dynamical interplay between turbulent particle transport (Γ) and Reynolds stress (ℜ) at the edge of toroidal magnetically confined plasmas is experimentally investigated on the basis of the cross-coupling between density and potential fluctuations in drift-wave turbulence. Both Γ and ℜ are found…

[Phys. Rev. E 111, 045207] Published Fri Apr 11, 2025

The Landslide Blog is written by Dave Petley, who is widely recognized as a world leader in the study and management of landslides.

Rail Advent has a very nice article that describes the now completed repair of the Browney Curve landslide on the East Coast Mainline railway line in England. This is a site that is dear to my heart as, for 14 years, I drove across the landslide on my way to work.

There is a Google Earth image from 2020, taken from a low sun angle, that beautifully illustrates the issues at this site:-

Google Earth image from 2020 showing the Browney Curve landslide site. Note the East Coast mainline railway running across the landslide.

The East Coast Mainline is one the most important long distance line the country. Built two centuries ago, the line links London and Edinburgh, via York and Newcastle. The Browney Curve landslide has caused issues for many years. The image below, from Network Rail, shows the scale of the problems:-

The Browney Curve landslide site. Image from Network Rail.

The hummocky terrain seen in the image is characteristic of land that is undergoing movement. The underlying surface geology consists primarily of glacial till, which causes stability issues in many locations in the UK. The embankment supporting the railway line runs below the very clear back scarp of a natural landslide, and there are clear signs of ground deformation on the slopes above and below the track.

The landslide has regularly caused damage to the track and the road, and there were concerns that a major movement could close the line for a protracted period. Prior to the works, the line was being intensely monitored at this location to ensure that the alignment was safe.

Network Rail has a good page detailing the remediation works, which primarily consist of the installation of 529 piles extending up to 25 metres into the ground to anchor the slope, plus extensive drainage works to lower pore water pressures. The gradient of the embankment has also been reduced, and there will be a tree planting programme as well.

Pell Frischmann has a good web page detailing the ground investigation and design works at the site. There is also a very good, very detailed review of the problems and the repairs on Youtube, presented by Pell Frischmann and Network Rail. This is a fantastic resource:-

The works have cost £33 million (US$43 million), representing a significant investment in the safety and resilience of the East Coast Mainline.

Return to The Landslide Blog homepage Text © 2023. 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.

Sustained scientific observations and monitoring are crucial for measuring ocean change, providing valuable data that contributes to a better understanding of oceanography, biodiversity, and the interconnectedness of global systems, and helps inform decisions about conservation and resource management.

What is the role of dissolved organic matter in the deep sea? In a study relating to this question, researchers from the Universities of Bremen and Oldenburg have investigated the composition of dissolved organic matter (DOM) in detail. Their samples were obtained during an expedition to the Guaymas Basin in the Gulf of California.

Nearly three-fourths of Earth is covered by oceans, making the planet look like a pale blue dot from space. But Japanese researchers have made a compelling case that Earth's oceans were once green, in a study published in Nature.

A warm cup of tea could offer some unexpected health benefits.

While steeping, tea leaves soak up lead ions from water, researchers reported in ACS Food Science and Technology. Though the process doesn’t completely purify the water and is not intended for large-scale water remediation, the passive benefit could help explain the correlation between regular tea consumption and lower incidences of heart disease and stroke.

“This idea that the tea bag, or tea within the bag, would absorb something was something nobody thought about.”

Tea is known to release various compounds such as tannins and caffeine into water. But “this idea that the tea bag, or tea within the bag, would absorb something was something nobody thought about,” said Vinayak Dravid, a coauthor of the study and a materials scientist at Northwestern University.

In the lab, Dravid and his research group regularly develop spongelike materials that absorb pollutants. The composition of one of these sponges reminded study coauthor Benjamin Shindel of tea bags, Dravid said. Shindel, at the time a Ph.D. candidate and now a materials scientist contracting with the U.S. Department of Energy, suspected that conditions inside a cup of tea would encourage metals to stick to the tea leaves.

To test the hypothesis, Shindel and his colleagues prepared solutions made of water with different concentrations of lead, ranging from 10 parts per billion—EPA’s trigger level for lead—to highly toxic levels of 10 parts per million. Then they heated the solutions to 85°C (185°F, just below the boiling point of water) and prepared different kinds of teas, including traditional black, green, oolong, and white teas brewed from the Camellia sinensis plant as well as the herbal teas rooibos and chamomile. After steeping the tea leaves for a range of times—anywhere from a few seconds to 4 hours—the researchers measured how much lead was left in each cup.

Spilling the Tea

Black and green teas were the most effective at removing lead, the team found, although the type of tea had less efficacy than the time it steeped. Finely grinding the leaves before steeping slightly improved their performance, likely because the increased surface area left more space for lead atoms to attach to the leaves. Steeping leaves in a cup of black tea for 5 minutes removed about 15% of the lead from the laboratory solutions. White and herbal teas, whose leaves remain smooth as they steep, were less effective.

The wrinkled surface of black tea leaves, seen here under a scanning electron microscope, may contribute to an increased surface area onto which lead and other metal ions adsorb. Credit: Vinayak P. Dravid Group/Northwestern University

The longer the leaves steeped, researchers found, the more lead adsorbed onto them. The longer leaves steep, however, the more bitter the tea becomes.

Tea’s metal-remediating benefits weren’t limited to lead. The team also prepared separate solutions of cadmium, chromium, copper, and zinc. Ions of each adsorbed onto the leaves.

In addition to the leaves themselves, the team also experimented with whether the type of tea bag influenced the amount of metal removed. Though nylon and cotton tea bags didn’t remove any lead, the metal did bind to cellulose (or “wood pulp”) tea bags.

Previous research has shown that C. sinensis can absorb metals from soil and store them in its leaves, so “there is always a risk, and obviously a concern, that you are actually then contributing those heavy elements and heavy toxins into water again when you make tea,” Dravid said.

But the new study suggests that metals will stick with the plant and not be released into the surrounding environment. “What our work showed,” Dravid explained, is that C. sinensis “has an affinity for heavy metals—that even if they exist in the leaf, they actually will remain. And that’s so reassuring.”

Brewing with Perspective

Tea leaves are not a substitute for existing methods of water purification, the authors emphasized. Most of the lead that enters drinking water does so through lead pipes connecting water mains and homes, and many domestic faucets or under-sink filters can remove more than 90% of lead ions.

Instead, tea leaves are “a way of reducing the lead exposure that occurs naturally,” explained Marc Edwards, an environmental engineer at Virginia Tech who was not involved in the study. Tea leaves could help mitigate—though not completely remove—the presence of other metals that enter drinking water either through corrosion (e.g., of copper or zinc pipes) or through erosion of mineral deposits like chromium.

“It’s not going to remove all the metal in the water.…But it is removing a fraction that may be meaningful from a public health perspective.”

“It’s not going to remove all the metal in the water, 99.9% or something like this,” Shindel agreed. “But it is removing a fraction that may be meaningful from a public health perspective.” If brewing tea removes 15% of lead and a person drinks enough tea to account for one fifth of their daily liquid consumption, that consumption could lower their lead intake by 3% compared with someone who drinks no tea.

This passive removal may help explain the observed relationship between tea consumption and a lower incidence of certain health issues such as heart disease, high blood pressure, and stroke, the researchers suggest. All three conditions have been associated with lead intake. But more research is needed to determine whether a direct link exists between tea consumption and metal intake, they said.

Though tea leaves can’t eliminate lead in water completely, their widespread use may help reduce an individual’s lead exposure over time.

Still, there’s no need to oversteep your morning cup, Shindel said. “I don’t think people should be changing their tea consumption patterns, or brewing really bitter tea…so they can get more metals out.”

—Skyler Ware (@skylerdware), Science Writer

Citation: Ware, S. (2025), Tea leaves remove lead from water, Eos, 106, https://doi.org/10.1029/2025EO250134. Published on 10 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

After decades of nondetections and tantalizing maybes, astronomers have definitively detected an aurora on Neptune. Using the James Webb Space Telescope (JWST), researchers detected an infrared auroral glow and the spectral signature of a key tracer of aurorae in Neptune’s upper atmosphere for the first time. The spectrum of this ionized molecule also suggests that Neptune’s upper atmosphere has cooled significantly since Voyager 2’s flyby 34 years ago.

Aurorae have been seen on planets and moons throughout the solar system. Theories predicted that Neptune should have aurorae, too, but previous attempts to detect them failed, said Henrik Melin, a planetary aurora researcher at Northumbria University in Newcastle upon Tyne, United Kingdom (U.K.).

“I’ve spent many, many nights up a mountain trying to detect this stuff using ground-based telescopes. You spend four nights staring at Neptune, and you see nothing,” Melin said.

This auroral detection is “completing the set” of giant planet aurorae, he added. “We have Jupiter, we have Saturn, we have Uranus. We now have Neptune.”

Chilly Aurora

Aurorae occur when charged particles from the solar wind or a nearby volcanic moon, for example, interact with a body’s magnetosphere and upper atmosphere. Some aurorae glow in visible light, like on Earth and some of Jupiter’s moons. Mercury’s aurorae shine in X-ray light.

On planets with hydrogen-dominated atmospheres like Jupiter, Saturn, and Uranus, aurorae typically glow in the infrared or ultraviolet and are traced by the presence of the trihydrogen cation (H3+). Anywhere they occur, aurorae can help scientists understand the inner workings of a planet’s magnetosphere.

“Auroral emissions provide important insight into the space environment of a planet.”

“Auroral emissions provide important insight into the space environment of a planet, and this is particularly important for Neptune, which has a very bizarre magnetic field,” said Jonathan Nichols, a planetary aurora researcher at the University of Leicester in the U.K. who was not involved with the new discovery.

Voyager 2’s brief 1989 flyby suggested that Neptune’s magnetic field is both tilted from its axis of rotation and offset from the center of the planet. The flyby also detected some hints of a possible aurora that astronomers have been hoping to confirm ever since. Models of Neptune’s atmosphere and magnetic field have suggested that Neptune’s aurorae should also be traceable by H3+ and have even predicted the longitudes at which they should appear. But detecting the aurorae proved elusive.

In June 2023, Melin and his colleagues obtained near-infrared JWST spectra of Neptune, originally intending to explore the circulation of Neptune’s middle atmosphere. The observations unexpectedly revealed an infrared auroral glow as well as a shockingly clear infrared spectrum of H3+ emitted by the planet’s upper atmosphere.

The intensity of the H3+ spectrum suggests that the upper atmosphere generating the aurora is 85°C (358 K), a significant cooldown from the 477°C (750 K) temperature measured by Voyager 2.

“It’s great to see this addition to the family portrait of solar system auroras.”

“That was quite a surprise,” Melin said.

Neptune’s seasons are roughly 41 Earth years long, so this dramatic cooling took place faster than the seasonal timescale. The researchers don’t yet understand what might be driving the cooldown, Melin said, though it is likely unrelated to the unseasonably cool summer observed elsewhere in Neptune’s atmosphere.

“The consequence of these really cold temperatures means that the auroral emissions are extremely faint,” Melin said. That explains why Neptune’s aurorae eluded the gazes of ground- and space-based telescopes before. “It was just really, really cold.”

“It’s great to see this addition to the family portrait of solar system auroras,” Nichols said. “Now we know how bright the infrared emission is, we can work out the intensity in other wavelengths such as ultraviolet, and we can run models to see what the upper atmosphere is like.”

The researchers published this discovery in Nature Astronomy.

A Neptunian Day

These JWST data were clear enough to trace aurorae to specific latitudes and longitudes, “producing the first map of the aurora at Neptune,” Melin said.

What’s more, the aurorae appeared at the exact longitudes in the southern hemisphere predicted by long-standing theories.

“This is the tantalizing starting point of really getting to understand Neptune.”

“This was not a given,” Nichols explained, “since the length of the planet’s day was determined more than 3 decades ago, and the uncertainty was such that we were supposed to have lost track of what the time is at any point on Neptune.” (Uncertainty in planetary day lengths is pretty common.)

“But it appears as if it is more accurate than we thought!” Nichols added.

Later this year, the team will point JWST at Neptune several times over the course of a month to learn more about what drives its aurorae and how the planet’s magnetosphere responds to different levels of solar activity.

“By studying the morphology of the aurorae and its changes over time, we can figure out what drives it,” Melin said. The team needs more data to do that, “but this is the tantalizing starting point of really getting to understand Neptune.”

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

This news article is included in our ENGAGE resource for educators seeking science news for their classroom lessons. Browse all ENGAGE articles, and share with your fellow educators how you integrated the article into an activity in the comments section below.

Citation: Cartier, K. M. S. (2025), After 30-year search, scientists finally find an aurora on Neptune, Eos, 106, https://doi.org/10.1029/2025EO250130. Published on 10 April 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Journal of Geophysical Research: Planets

The longer a magma chamber resides in the upper crust, the more likely it will evolve to silica-rich compositions. Volcanism has been active on Mars throughout its history, but there is an apparent lack of widespread evolved magmatism, and the development of magma storage systems has been poorly constrained.

To better understand how crustal depth and temperature profile affect the evolution and growth of magma chambers on Mars, Chatterjee et al. [2025] utilize numerical modeling and compare with recent results from the InSight lander mission. Their models suggest that Mars’ crust is divided into three zones that are consistent with InSight seismic data: (1) the upper crust where small intrusions, such as dikes, dominate the upper crust; (2) the lower crust where larger magma chambers can develop and grow; and (3) a middle zone where magma chambers can occasionally grow and produce dikes that erupt at the surface.

The depths where the three magma storage zones are located depend on the crust’s temperature gradient and this study is the first to model the longevity of magma chambers on Mars as it has gradually cooled over geological time. A higher temperature gradient during Mars’ early history (the Noachian and Hesperian time periods) would have allowed larger, more long-lived upper crustal chambers to develop with the potential to feed eruptions at the surface. Seismic activity in Cerberus Fossae detected by InSight is consistent with magmatism and suggests its continued influence on the structure and make-up of the crust of Mars.

Citation: Chatterjee, A. P., Huber, C., Head, J. W., III, & Bachmann, O. (2025). Magma chamber longevity on Mars and its controls on crustal structure and composition. Journal of Geophysical Research: Planets, 130, e2024JE008798. https://doi.org/10.1029/2024JE008798

—Mariek E. Schmidt, Associate Editor, JGR: Planets

Text © 2024. 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.

Author(s): Srimanta Maity and Garima Arora

High-field terahertz (THz) pulse generation is investigated through the interaction of an intense single-color CO2 laser pulse with helium (He) gas targets. Employing particle-in-cell (PIC) simulations, this study reveals a substantial enhancement in THz generation efficiency, even with a single-col…

[Phys. Rev. E 111, 045205] Published Thu Apr 10, 2025

The Landslide Blog is written by Dave Petley, who is widely recognized as a world leader in the study and management of landslides.

On 8 May 2022, the catastrophic Baiyan rock avalanche occurred in Zhijin County, which is located in Guizhou Province, China. The digital lat/long is [26.63771, 105.69200]. I described this event at the time (on the old AGU blogsite). It destroyed 53 houses, killing three people.

Intriguingly, many of the reports of this event seem to have been removed, such as the 163.com news item and the Youtube video. This is the image of the failure that I posted at the time:-

The 8 May 2022 Baiyan rock avalanche in Bijie, Guizhou. Image from 163.com.

There is a very interesting new paper (He et al. 2025) about this event in the journal Landslides. The aim of the paper is to examine the behaviour of the particles that formed the rock avalanche using a very impressive combination of a drone survey and articial intelligence driven analysis of individual particles. This is fascinating work, which demonstrates that underlying topography plays a large role in determining the runout characteristics of individual blocks.

But along the way, the paper also provides some very interesting information about the Baiyan rock avalanche itself. First, the slope from which this failure occurred had suffered an astonishing total of seven other rock avalanches in the period between 2019 and 2022. The Google Earth image below, from March 2022 (i.e. before the Baiyan rock avalanche) shows the problems that were occurring on the slope:-

Google Earth image of the site of the 8 May 2022 Baiyan rock avalanche in China.

According to He et al. (2025), the Baiyan rock avalanche itself had a volume of 36,000 cubic metres. It had a runout distance of about 560 metres and a vertical height difference of about 455 m. Significant, but not exceptional, rainfall occurred in the days leading up to the collapse.

Tucked away towards the end of the article is a fascinating consideration of the causes of this event, and of the extraordinary cluster of failures that occurred in this area at the time. Underground coal mining was being undertaken directly below this slope – He et al. (2025) show that a panel advanced from the SW to the NE directly below the ridgeline, starting in the southwest in October 2021. In May 2022, the mining activities were occurring directly below the source area of the Baiyan rock avalanche. The implication is clearly that disturbance / subsidence caused fracturing of the rock mass, triggering the failure.

That comparatively shallow coal mining was occurring directly below such a sensitive location is perhaps surprising. This should be a classic case study of the impacts of poorly controlled mining on slope stability. I also wonder why the village was not evacuated before the landslide given the multiple failures that were occurring on the slope directly behind. It would be interesting to know more about the analyses and discussions that were occurring at this location in the early months of 2022.

Reference

He, J., Zhang, Y., Sun, P. et al. 2025. Investigation of deposition characteristics using a novel super-resolution method: a case study of Baiyan rock avalanche in Guizhou, China. Landslides. https://doi.org/10.1007/s10346-025-02512-z

Return to The Landslide Blog homepage Text © 2023. 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.

SummaryLocating earthquakes plays an important role in the study of seismic activity and geological structures. Traditional methods for locating earthquakes mainly rely on waveform matching and travel time fitting. With the development of artificial intelligence technology, machine learning methods have often been applied to locate earthquakes. However, current machine learning approaches may face challenges related to physical constraints. In this study, we build a 3D U-Net network with station distribution constraints to locate earthquakes. To improve the generalizability of the network model, we apply data augmentation techniques, including data shifting, selection, rotation, and fusion. The location results are evaluated using a testing dataset from Oklahoma, showing an average location error of about 5 km. The origin time can be determined based on the earthquake's location and the waveforms recorded by stations through waveform shifting and stacking. This method does not require the complex processing steps of traditional seismic approaches, allowing for rapid earthquake location. Additionally, we apply the network model to data recorded in Southern California through transfer learning for further application. The results show that this new method is stable and generalized, making it applicable to earthquake location problems associated with arbitrary station networks. Furthermore, we discuss the effects of data augmentation, network architecture, and the Gaussian radius of labels on the outcomes. These insights help us better understand machine learning algorithms and improve the application of deep learning in earthquake location.

SummaryEvidence of seismic anisotropy is widespread within the Earth, including from individual crystals, rocks, borehole measurements, active-source seismic data, and global seismic data. The seismic anisotropy of a material determines how wave speeds vary as a function of propagation direction and polarization, and it is characterized by density and the elastic map, which relates strain and stress in the material. Associated with the elastic map is a symmetric 6 × 6 matrix, which therefore has 21 parameters. The 21-dimensional space of elastic maps is vast and poses challenges for both theoretical analysis and typical inverse problems. Most estimation approaches using a given set of directional wavespeed measurements assume a high-symmetry approximation, typically either in the form of isotropy (2 parameters), vertical transverse isotropy (radial anisotropy: 5 parameters), or horizontal transverse isotropy (azimuthal anisotropy: 6 parameters). We offer a general approach to explore the space of elastic maps by starting with a given elastic map T. Using a combined minimization and projection procedure, we calculate the closest Σ-maps to T, where Σ is one of the eight elastic symmetry classes: isotropic, cubic, transverse isotropic, trigonal, tetragonal, orthorhombic, monoclinic, and trivial. We apply this approach to 21-parameter elastic maps derived from laboratory measurements of minerals; the measurements include dependencies on pressure, temperature, and composition. We also examine global elasticity models derived from subduction flow modeling. Our approach offers a different perspective on seismic anisotropy and motivates new interpretations, such as for why elasticity varies as a function of pressure, temperature, and composition. The two primary advances of this study are 1) to provide visualization of elastic maps, including along specific pathways through the space of model parameters, and 2) to offer distinct options for reducing the complexity of a given elastic map by providing a higher-symmetry approximation or a lower-anisotropic version. This could contribute to improved imaging and interpretation of Earth structure and dynamics from seismic anisotropy.

SummaryAutomatic event detection and phase picking are critical for processing the large volumes of data produced by modern seismological instrumentation. Accurate picking is especially challenging in Distributed Acoustic Sensing (DAS) recordings, where data quality can significantly vary along segments of the fiber due to localized environmental noise and coupling issues, reducing signal-to-noise ratios (SNR). Similarly, Ocean Bottom Seismometer (OBS) data quality also suffers from these issues. To improve accuracy under diverse conditions, we developed a novel multiband kurtosis-based picking algorithm, Kurtosis-Value-Picker (KVP), that enhances phase picking for both impulsive and emergent seismic signals. Our approach uses characteristic functions (CFs) calculated with sliding windows across multiple frequency bands. Triggers are identified based on localized kurtosis jumps over a few samples, providing greater sensitivity to emergent signals than traditional finite-difference methods. Each individual CF has its own set of triggers, adding flexibility to phase picking and retaining spectral information. We validate the KVP algorithm using earthquake data recorded with DAS on two land and submarine fiber-optic cables, as well as OBS data. We also compare its performance with a widely-cited, kurtosis-based algorithm, the widely-used FilterPicker algorithm, and the well-known PhaseNet model, using impulsive signals on nearby DAS channels as a ground truth for emergent arrivals. Our results demonstrate that KVP provides accurate picks and is suitable for complex seismic datasets.

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.

The Trump administration has canceled funding used to coordinate the National Climate Assessment, a major, congressionally mandated U.S. climate change report produced through the U.S. Global Change Research Program (USGCRP).

The National Climate Assessment is published approximately every four years and is the United States’ broadest assessment of current climate change impacts and climate science. 

NASA canceled a contract with ICF International, a consulting firm. ICF International was hired by the agency to support USGRCP’s logistical work and help coordinate the expansive assessment, which involves input from 15 federal agencies and hundreds of authors and contributors.

ICF previously supported the development and release of the Fifth National Climate Assessment and the Fourth National Climate Assessment. 

The change likely means the Sixth National Climate Assessment, planned for publication by early 2028, won’t be completed.

I can't say this was unexpected, but it is deeply, deeply disappointing nonetheless. The #NCA6 is now up in the air – at best.Some problems go away on their own. This is not one of them.It is coming. It's already here. You can either be prepared or unprepared.

— Cullen Hendrix (@cullenhendrix.bsky.social) 2025-04-09T16:15:43.477Z

Congress requires the Sixth National Climate Assessment to move forward, but federal officials involved in USGCRP work told Politico that the assessment is likely dead without the support of ICF International staff. Two dozen staff at the USGCRP will lose the funding to support their roles, Science reported.

 
Related

•  Trump Moves to Hobble Major U.S. Climate Change Study
•  Trump Team Takes Aim at Crown Jewel of U.S. Climate Research
•  Trump Administration Fires Staff for Flagship U.S. Climate Assessment
•  Get Involved: AGU Science Policy Action Center
 

The move is not a surprise to those who have been following Trump’s actions on climate change. Russell Vought, the current director of the Office of Management and Budget for the Trump administration, has previously recommended ditching the National Climate Assessment and firing scientists who worked on previous editions of the report.

The cuts come alongside other efforts from the Trump Administration to undermine climate change research including cutting funding to cooperative agreements between U.S. universities and federal agencies to study Earth systems and climate change. 

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

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. Text © 2024. 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.