The morning of 23 July 2024 was like most summer mornings in Yellowstone National Park. Cars vied for parking spaces, bison lounged in meadows, and tourists strolled along boardwalks taking in sights of bubbling springs and spouting plumes of water and steam. All were unaware of the pressure that had built underneath Black Diamond Pool, a thermal spring in Wyoming’s Biscuit Basin about 3.5 kilometers northwest of famed Old Faithful Geyser.

Suddenly, just before 10:00 a.m., jets of muddy, rock-laden water and steam shot from the turbid depths of the pool, building into bursts as high as 400–600 feet (~120–180 meters) that showered the surrounding area and boardwalk with rocks and mud. Water from the pool surged toward the nearby Firehole River, carrying boulders and debris, and a steam plume was visible from kilometers away.

Fifty-five seconds after the explosion began, it was over. Left behind was a roughly 1-square-kilometer debris field, as well as many stunned onlookers, fresh from scrambling away from the unexpected outburst and wondering what had just happened.

Safety was the paramount concern in the immediate aftermath of the event. But scientists also mobilized quickly to monitor for additional activity and to collect timely observations that could help piece together why the explosion happened. On a longer timescale, federal, state, and academic organizations are working together to better understand the dynamics and triggers of hydrothermal explosions to recognize warning signs of future events before they occur.

What Are Hydrothermal Explosions?

Hydrothermal explosions, like the July 2024 event at Black Diamond Pool (Figure 1), occur in many volcanic-hydrothermal areas around the world. When a pressurized hot water reservoir instantaneously decompresses, superheated water violently flashes to steam that has enough energy to break surrounding rock [Muffler et al., 1971; Thiéry and Mercury, 2009; Browne and Lawless, 2001; Montanaro et al., 2022].

Such explosions exist on a continuum from large, destructive events to smaller geyser eruptions that routinely spew water and steam into the air. Geysers are caused by constrictions in hydrothermal plumbing systems that temporarily trap boiling water and steam until the pressure is high enough for the water to erupt. Hydrothermal explosions, on the other hand, occur less frequently. They are primed by the gradual pressure increase in a confined system, followed by rapid decompression caused either by rupturing of a hydrothermal seal or by an external event like a landslide or earthquake. Large geyser eruptions can destroy geysers’ plumbing systems and throw rock and mud like hydrothermal explosions, and small, spontaneously reoccurring hydrothermal explosions may arguably be more consistent with geyser activity.

In Yellowstone National Park, the occurrence of hydrothermal explosions has been recognized for decades. Since the end of the most recent glaciation roughly 14,000 years ago, at least 18 massive hydrothermal explosions have formed craters ranging from 300 to 2,500 meters across, the largest of which—formed about 13,800 years ago—is the biggest explosion crater on Earth [Muffler et al., 1971; Morgan et al., 2009; Christiansen et al., 2007].

More than 2 dozen hydrothermal explosions have been documented within Yellowstone National Park since its founding in 1872 [Christiansen et al., 2007]. One of the best-observed events prior to 2024 was the explosion of Porkchop Geyser in Norris Geyser Basin on 5 September 1989 [Fournier et al., 1991]. That event—witnessed by nine people, none of whom were injured—threw small rocks and debris 60 meters from the vent and left a crater more than 10 meters wide.

Smaller hydrothermal explosions occur more frequently than larger ones (maybe as often as annually), but they usually go unwitnessed because they occur in the backcountry, at night, or during winter months. Hydrothermally active areas around the world sometimes show signs of instability or increases in temperature prior to an explosion; however, there are no known universal precursory signals upon which forecasts can be based.

Keeping Watch over Yellowstone’s Activity

The lack of knowledge about hydrothermal explosion occurrence rates, precursory signals, and triggers motivated the Yellowstone Volcano Observatory (YVO), a consortium of nine federal, state, and academic organizations, to include hydrothermal processes and hazards in its recently developed hazards monitoring plan [Yellowstone Volcano Observatory, 2022]. The plan includes the installation of broadband seismic, infrasound, thermal, and deformation sensors within geyser basins to better detect anomalous hydrothermal activity and investigate the potential to forecast hazardous events.

A prototype hydrothermal monitoring station, installed in Norris Geyser Basin in 2023, immediately paid dividends. The station clearly detected infrasound signals from nearby geyser eruptions and a small hydrothermal explosion that occurred on 15 April 2024—the first hydrothermal explosion in Yellowstone National Park to be documented by instrumental monitoring [Poland et al., 2025].

However, no hydrothermal monitoring station was installed at Biscuit Basin in July 2024, and YVO’s volcano monitoring network barely detected the explosion, even though it was big enough to destroy a section of boardwalk adjacent to Black Diamond Pool. The destructive event—thankfully, no injuries resulted—emphasizes the importance of expanded monitoring in geyser basins of Yellowstone National Park. It also highlights the risk posed by even small explosions that occur when people are nearby.

Much remains unknown about the processes leading to hydrothermal explosions and how best to safeguard the more than 4 million visitors to Yellowstone National Park every year from this underappreciated hazard [e.g., Montanaro et al., 2022]. The goal of postexplosion scientific investigations is to develop understanding that will enable better monitoring, detection, and, potentially, forecasting of future dangerous hydrothermal events.

Black Diamond Pool’s Explosive Past and Present

Explosive activity has recurred sporadically at Black Diamond Pool over its roughly 120-year life. Broken, angular rocks from previous explosions that were cemented back together before being ejected on 23 July 2024 provide evidence of this repeated explosive activity.

According to early geologic maps and photographs, Black Diamond Pool did not exist before 1902. It likely formed dramatically from a hydrothermal explosion sometime between then and 1912. Documents preserved in the Yellowstone National Park archives reference a few short periods of explosive activity that enlarged the new pool and formed two additional springs.

The area was quiet after 1960 until a series of short explosive events of varying intensity (though none approaching the scale of the July 2024 event) reinitiated in 2006. The frequent activity ceased by early 2013, and only three isolated events were reported between then and July 2024.

The 23 July hydrothermal explosion—which occurred during the park’s busiest month—stunned tourists, National Park Service (NPS) officials, and the scientific community. Visitation numbers had peaked a few days earlier, and on the day of the explosion, cameras recorded 209 visitors to Biscuit Basin by 9:00 a.m. Within minutes of the approximately 10:00 a.m. event, law enforcement rangers arrived on the scene and quickly closed the basin to the public to prevent injuries should explosive activity continue.

YVO’s initial response primarily involved communicating to the public and emergency managers about the cause of the event and the potential for additional activity. Observatory scientists also fielded numerous media inquiries.

Coordination of the scientific response began in parallel with these communications activities. YVO scientists and experienced collaborators from other institutions deployed to the field within hours to days to install monitoring equipment and gather time-sensitive data using a variety of approaches.

Fanning Out in Biscuit Basin

Working near an unstable, potentially explosive pool in the immediate aftermath of the explosion was an exercise in situational awareness, but the extensive training and experience of the scientists involved helped to ensure their safety.

Field teams worked in pairs, with one person keeping an eye out for signs of an ensuing explosion while the other collected data. High-temperature areas surrounding the pool suggested the presence of boiling water or steam underneath a thin crust where the ground could easily collapse or another explosion could break out. Near the pool edge, slippery mud and overhangs that could crumble unexpectedly into the pool also posed particular hazards.

The field teams also knew that newly unsealed hydrothermal systems can emit higher-than-normal amounts of hazardous gases. Thankfully, blowing winds following the explosion diluted potentially dangerous concentrations as well as the strong perfume of acid, sulfur, and hydrocarbons, helping the teams get on with their work.

Geology and Mapping. Hydrothermal explosions leave behind debris fields that can be used to discern many properties of the explosions [Breard et al., 2014]. For example, the size and distribution of ballistic blocks around the vent provide clues about the energy of the explosion. This information also enables calculations of ballistic vulnerability—the probability of a human fatality at any given location around the vent in the event of another explosion of similar size. In addition, rocks excavated from the preexisting subsurface hydrothermal system are useful for understanding the pressure and temperature conditions before the explosion and how sealed the system was.

Field teams from Colorado State University, NPS, and the University of California, Berkeley documented the sizes, distribution, and lithology of ballistic blocks thrown by the explosion to begin piecing together what the underlying hydrothermal system looked like before and during the explosion. NPS also used an uncrewed aerial vehicle to collect thermal and structure-from-motion imagery of the deposits and the surrounding area. These images helped identify areas with elevated temperatures and quantify the volume of material ejected by the 23 July explosion.

Near-Surface Geophysics. Dense seismic networks, which can sense the vibrations of bubbles and the brecciation of rock, are powerful tools for resolving subsurface hydrothermal plumbing, detecting small explosions, and helping scientists assess hazards from ongoing activity.

To record seismic signals in the aftermath of the explosion at Black Diamond Pool, the University of Utah deployed a temporary array of 33 seismometers around the pool by 26 July, and the instruments recorded for about 2 months. Four infrasound microphones were also deployed roughly 300 meters northwest of the pool from 19 August to 18 October. These data will be processed to pinpoint and explore signals from geyser activity and subsequent small hydrothermal explosions in Biscuit Basin.

Several weeks after the explosion, field teams from the University of Wyoming and NPS collected nuclear magnetic resonance (NMR), electrical resistivity (ER), and transient electromagnetics (TEM) datasets. NMR data provide estimates of the volume and location of water stored in the subsurface, including in confining, low-permeability zones. ER, which measures resistivity encountered by electrical currents, is ideal for identifying water-saturated subsurface pathways, as hydrothermal waters contain dissolved salts and are electrically conductive. TEM uses pulses of electric current to induce electric and magnetic fields underground. How fast these fields decay is another indication of variations in subsurface resistivity.

Together these techniques paint 3D views of hydrothermal fluids and lithological contrasts in the subsurface—important information for understanding the conditions and characterizing hazard potential in the postexplosion Black Diamond Pool system.

Water and Gas Chemistry. Gas emissions and water chemistry data were collected after the 23 July explosion by the U.S. Geological Survey (USGS), Montana Technological University, and the University of Wyoming to help probe underground processes.

Gridded measurements of carbon dioxide gas efflux, for example, provide information on spatial variations in diffuse gas fluxes at the surface that can be used to map subsurface gas pathways. Simultaneous measurements of isotopes of the short-lived radioactive gas radon in the same samples used for carbon dioxide measurements can help identify the sources of emissions and timescales of gas movement.

The chemical composition of the water in Black Diamond Pool is important because the solubility of different chemical species depends on the temperature at which water and rocks react. Critically, silica solubility decreases with decreasing temperature, and as hydrothermal waters cool, amorphous (noncrystalline) silica precipitates in subsurface flow paths [Fournier, 1985].

Past analyses of water chemistry at Black Diamond Pool have indicated that water and rocks there react at lower temperatures compared with systems farther south in Upper Geyser Basin, including at Old Faithful [Price et al., 2024]. These lower temperatures are more favorable for silica precipitation and may contribute to sealing flow paths and building pressure for hydrothermal explosions in Biscuit Basin.

Early Insights into the 2024 Explosion

The data collected following the explosion of Black Diamond Pool on 23 July 2024 are still being analyzed to provide a detailed account of the conditions preceding and following the event. However, some preliminary insights are available from the initial observations.

Many indicators point to the explosion being caused by self-sealing in the hydrothermal system, with the result that increases in subsurface pressure eventually overcame the strength of the sealing rocks—a common mechanism for hydrothermal explosions globally [Morgan et al., 2009; Montanaro et al., 2022]. The lack of a strong earthquake nearby, either before or during the explosion, indicates it was not seismically triggered.

Furthermore, some of the ejected debris—namely, minimally altered, high-porosity, and high-permeability conglomerates and sandstones—likely contained much of the liquid water that flashed to steam and powered the explosion (Figure 2). On the other hand, completely silicified and intensely altered low-permeability rocks also found in the debris field likely constituted the seal that contained the pent-up pressure before the explosion.

The initial analyses of the seismic and infrasound data, as well as observations from scientists and passing visitors, indicate that small explosions at Black Diamond Pool have continued since 23 July 2024 through to the present, posing an ongoing hazard. Some of these explosions have been accompanied by water surges flowing east into the nearby Firehole River and have been large enough to carry seismic instruments several meters downhill and partially bury others in fine sediment. Two witnessed events were observed to throw water, mud, and small rocks 20–30 feet (6–9 meters) into the air. A webcam installed in mid-May 2025 to better document activity at Black Diamond Pool captured a similar small eruption on 31 May 2025.

Better Science for Better Response

The scientific response to the 23 July 2024 hydrothermal explosion has focused on improving understanding of the event to inform strategies that can be used to detect, and potentially forecast, similar future explosions. New hazard maps and recent geophysical investigations will guide NPS’s response to ensure public safety within Biscuit Basin, helping to address specific questions such as when the basin can be reopened, whether walkways must be relocated, and what the short-term probability of another large explosive event at Black Diamond Pool is. Scientific investigation will also guide YVO’s efforts to deploy targeted monitoring to other hydrothermal areas in Yellowstone National Park.

Hydrothermal explosions in Yellowstone National Park are an underappreciated hazard, and a pressing need exists to better understand where, why, and how often they happen. Filling these knowledge gaps requires multidisciplinary studies that consortia like YVO and its collaborators are well suited to undertake. Ultimately, improved monitoring of hydrothermal hazards will aid risk assessment and mitigation and help park officials and visitors avoid dangerous situations in Biscuit Basin, elsewhere in Yellowstone National Park, and at hydrothermal systems worldwide.

Acknowledgments

We especially thank Jamie Farrell, who assisted with preparation of this article and led the deployment of temporary seismometers and infrasound arrays in Biscuit Basin after the July 2024 explosion. We also acknowledge the many people involved in event response, scientific investigation, and management and policy decisions associated with the 23 July 2024 explosion of Black Diamond Pool. Scientists and personnel from USGS, NPS, Colorado State University, the University of Utah, the University of Wyoming, and Montana Technological University who have contributed include Phillip Kondracki, Alex Hammerstrom, Kiernan Folz-Donahue, Elle Blom, Blaine McCleskey, Sara Peek, Shaul Hurwitz, Steven Rice, Carrie Guiles, Jaclyn Mcllwain, Hillary Robinson, Andy Parkinson, Lexi Peterson, Lisa Morgan, Pat Shanks, Greg Vaughan, Jen Lewicki, Alycia Cox, Michael Loya, Andrew Miller, Katie Copeland, Kallen Snow, and Adaeze Ugwu. We thank Shaul Hurwitz and Patrick Muffler for constructive reviews. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. government.

References

Breard, E. C. P., et al. (2014), Using the spatial distribution and lithology of ballistic blocks to interpret eruption sequence and dynamics: August 6 2012 Upper Te Maari eruption, New Zealand, J. Volcanol. Geotherm. Res., 286, 373–386, https://doi.org/10.1016/j.jvolgeores.2014.03.006.

Browne, P. R. L., and J. V. Lawless (2001), Characteristics of hydrothermal eruptions, with examples from New Zealand and elsewhere, Earth Sci. Rev., 52(4), 299–331, https://doi.org/10.1016/S0012-8252(00)00030-1.

Christiansen, R. L., et al. (2007), Preliminary assessment of volcanic and hydrothermal hazards in Yellowstone National Park and vicinity, U.S. Geol. Surv. Open File Rep., 2007-1071, 94 pp., https://pubs.usgs.gov/of/2007/1071/.

Fournier, R. O. (1985), The behavior of silica in hydrothermal solutions, in Geology and Geochemistry of Epithermal Systems, Rev. Econ. Geol., vol. 2, edited by B. R. Berger, P. M. Bethke, and J. M. Robertson, pp. 45–61, Soc. of Econ. Geol., Littleton, Colo., https://doi.org/10.5382/Rev.02.03.

Fournier, R. O., et al. (1991), Conditions leading to a recent small hydrothermal explosion at Yellowstone National Park, Geol. Soc. Am. Bull., 103(8), 1,114–1,120, https://doi.org/10.1130/0016-7606(1991)103%3C1114:CLTARS%3E2.3.CO;2.

Montanaro, C., et al. (2022), Phreatic and hydrothermal eruptions: From overlooked to looking over, Bull. Volcanol., 84(6), 64, https://doi.org/10.1007/s00445-022-01571-7.

Morgan, L. A., W. C. P. Shanks III, and K. L. Pierce (2009), Hydrothermal processes above the Yellowstone magma chamber: Large hydrothermal systems and large hydrothermal explosions, Spec. Pap. Geol. Soc. Am., 459, https://doi.org/10.1130/2009.2459(01).

Muffler, L. J. P., D. E. White, and A. H. Truesdell (1971), Hydrothermal explosion craters in Yellowstone National Park, Geol. Soc. Am. Bull., 82(3), 723–740, https://doi.org/10.1130/0016-7606(1971)82[723:heciyn]2.0.co;2.

Poland, M. P., et al. (2025), The first instrumentally detected hydrothermal explosion in Yellowstone National Park, Geophys. Res. Lett., 52(11), e2025GL115850, https://doi.org/10.1029/2025GL115850.

Price, M. B., et al. (2024), Historic water chemistry data for thermal features, streams, and rivers in the Yellowstone National Park area, 1883–2021, data release, U.S. Geol. Surv., Reston, Va., https://doi.org/10.5066/P9KSEVI1.

Thiéry, R., and L. Mercury (2009), Explosive properties of water in volcanic and hydrothermal systems, J. Geophys. Res. Solid Earth, 114(B5), B05205, https://doi.org/10.1029/2008JB005742.

Yellowstone Volcano Observatory (2022), Volcano and earthquake monitoring plan for the Yellowstone Caldera system, 2022–2032, U.S. Geol. Surv. Sci. Invest. Rep., 2022-5032, 23 pp., https://doi.org/10.3133/sir20225032.

Author Information

Lauren Harrison (lauren.n.harrison@colostate.edu), Colorado State University, Fort Collins; Michael Poland, Yellowstone Volcano Observatory, U.S. Geological Survey, Vancouver, Wash.; Mara Reed, University of California, Berkeley; Ken Sims, University of Wyoming, Laramie; and Jefferson D. G. Hungerford, National Park Service, Mammoth, Wyo.

Citation: Harrison, L., M. Poland, M. Reed, K. Sims, and J. D. G. Hungerford (2025), Hydrothermal hazards on display in Yellowstone National Park, Eos, 106, https://doi.org/10.1029/2025EO250233. Published on 27 June 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.

Boots On the Ground

“There’s no roads, there’s no helicopters, there’s not even a donkey.”

It’s just another day in the field.

The spartan accommodations available to scientists tracking Uganda’s dwindling glaciers is not universal to geoscience fieldwork, but they’re a good indication of the lengths to which scientists will go—enthusiastically—to discover and document our planet’s particularities. Read all about it in “A New 3D Map Shows Precipitous Decline of Ugandan Glaciers.”

Volcanologists on La Palma, the largest of the Canary Islands, faced a different challenge during their work in the field: an actively erupting volcano. In “Volcanic Anatomy, Mapped as It Erupts,” Vittorio Zanon and Luca D’Auria share how near-real-time petrological analyses can help support the safety of surrounding communities as well as associated scientific efforts.

Scientists on an Antarctic research cruise found themselves stymied by sea ice. But when a Chicago-sized ice shelf unexpectedly calved, the crew quickly pivoted and discovered a surprisingly “Thriving Antarctic Ecosystem Revealed by a Departing Iceberg.”

Far from being stranded, scientists “Tracking Some of the World’s Fiercest Ocean Currents” around the Mozambique Channel found that the eddy-ring dipoles there transport nutrients and biota at a rate of 1.3 meters per second.

Hazards like volcanoes, ice shelves, and ocean currents may ultimately be no match for the “looming catastrophes—funding cuts, software obsolescence, and loss of community support,” however. To this end, the data scientist–authors of “The Valuable, Vulnerable, Long Tail of Earth Science Databases” share research-based recommendations for supporting expert community-curated data resources.

Geoscience fieldwork is globe-spanning and mind-bending, and we hope you enjoy the ride.

—Caryl-Sue Micalizio, Editor in Chief

Citation: Micalizio, C.-S. (2025), Worldwide fieldwork, Eos, 106, https://doi.org/10.1029/2025EO250220. Published on 23 June 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.

Next time you explore a beach or a desert, look down at the sand. You might spot patches of small ripples just a few centimeters tall. Wind can shape these miniature dunes in less than half an hour and blow them away just as quickly. Unlike the processes that form larger dunes that define desert landscapes and shorelines, those that shape mini dunes have been elusive.

“There have been some observations of such small, meter-scale bedforms, but not many quantitative studies,” said Camille Rambert, a doctoral student at École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris and lead author on the new research. “And there have not been any models to explain their formation.”

Recently, a group of researchers used high-resolution laser scanning in the Namib Desert in Namibia to watch how tiny dunes form. Those scans informed dune formation models, which found that the key factor is how sand grains bounce on smooth versus grainy surfaces.

Blowing in the Wind

Although small sand bedforms are a common phenomenon in most sandy places, their ephemeral nature has made it challenging for geomorphologists to decode what makes a small dune form where only flat, featureless sand exists.

A team of researchers, including Rambert, set out to the Namib Desert in coastal southern Africa seeking to understand how these bedforms take shape. The team used a laser scanner sitting on the surface to collect repeated high-resolution topographic maps of nearby flat areas, roughly 5 meters wide × 5 meters long, nestled between larger dunes. The scanner measured the distance from the laser emitter to the ground and also measured near-surface wind speed and direction. The team could detect vertical changes to the surface of about half a millimeter and horizontal changes of about a centimeter.

“From those measurements, we can deduce how bedforms evolve,” Rambert said. “Do they grow and migrate, or do they shrink?”

They developed a mini dune formation model on the basis of well-established physics governing large dune formation, but with a key twist: The small dunes started on consolidated surfaces like gravel or hard-packed sand rather than on an erodible foundation such as loose sand. That difference altered how far wind could transport a sand grain and how the grain bounced or stuck when it landed.

“This difference in surface materials affects the sand transport,” Rambert said. “More sand can be transported on a consolidated surface than on the erodible surface.”

If a grain wasn’t swept away by the next gust of wind, its presence made the surface a little rougher and more likely to trap the next grain of sand—and the next. The gradual buildup of grains into tiny bumps altered near-surface wind patterns, which helped trap even more sand and created distinctive dune patterns in the bedform.

These patches of mini dunes disappeared when a strong enough wind blew the sand grains off the consolidated surface. If the wind had been gentler, those patches might have continued growing.

The team found that their model observations accurately portrayed what they saw in the laser scans from the Namib. They published these results in Proceedings of the National Academy of Sciences of the United States of America.

“This study highlights the importance of bed heterogeneities, such as whether a surface is sand covered or not, in how meter-scale bedforms evolve,” Joel Davis, a planetary geologist at Imperial College London in the United Kingdom, wrote in an email. Davis was not involved with the research. “It’s intriguing [that] those small-scale variations in dynamics…could influence whether these small bedforms become a larger dune field, or simply disappear.”

Dunes Beyond Earth

Scientists have discovered dunes on both Mars and Saturn’s moon Titan, but the instruments that have explored those distant worlds are far less advanced than the laser scanners on Earth.

“Studies like these, on the dynamics of Earth dunes, are particularly useful for investigating dunes in a planetary setting, such as on Mars or Titan,” wrote Davis, who studies Martian dunes.

Some of Mars’s dunes form inside craters, which presumably trap a lot of loose sand, but they are also found outside the craters in less sandy areas. “We don’t really know why they have formed in these locations, but perhaps bed heterogeneities are a control on this,” Davis wrote. “It would be interesting to see if we could identify any metre-scale bedforms in these expansive interdune areas of Mars…similar to the Namibia examples.”

What’s more, Earth’s dunes tend to be either very short (centimeters) or very long (tens to hundreds of meters). Though hundreds of dunes near Mars’s north pole are the same shape as Earth dunes, most of them are 1–2 meters long. Planetary geologists are still puzzling over this.

“This is a hotly debated topic that is rapidly evolving,” wrote Lior Rubanenko in an email. Rubanenko is a planetary surfaces researcher at the Planetary Science Institute in Tucson, Ariz., who was not involved with the new research.

“Mars, and also other planetary bodies such as Titan, are, in a way, laboratories where the physical conditions are different than on Earth­—different atmospheric density, different grain size and material type,” Rubanenko wrote. “This allows us to conduct and observe ‘planet-size’ experiments which challenge our current paradigms.”

“Comparing observations of dunes between these planets can help us better understand the mechanisms that govern sand transport and dune formation,” he added.

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

Citation: Cartier, K. M. S. (2025), Mini dunes form when sand stops bouncing, Eos, 106, https://doi.org/10.1029/2025EO250216. Published on 11 June 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.

Antarctica is Earth’s most remote continent, barely touched by human activities.

It is, however, not immune to the kind of environmental damage that plagues more populated parts of the world. In a new study, researchers found chemicals originating from everyday personal care products (PCPs), such as cosmetics, detergents, pharmaceuticals, and deodorants, in Antarctic snow.

Contaminants in PCPs—loosely defined as semivolatile organic compounds that are industrially produced at a global scale, used in large volumes, and relatively persistent in the environment—are increasingly being recognized as pollutants. Both the Arctic Monitoring and Assessment Programme and the Scientific Committee on Antarctic Research have encouraged further research on PCP ingredients and the creation of monitoring plans for tracking their presence at the poles.

Looking for these pollutants, researchers collected 23 surface snow samples from 18 sites along the Ross Sea coast during the Antarctic summer of 2021–2022. Though some sampling locations were near areas with human activity, including Italy’s seasonally occupied Mario Zucchelli research station, the majority were situated hundreds of kilometers from human settlements.

The scientists reached these remote locations by piggybacking on helicopter rides transporting other teams maintaining weather stations or deploying scientific instruments. “This way we halved the impact of our sampling, because they needed to go there in any case,” said Marco Vecchiato, an analytical chemist at Ca’ Foscari University in Venice, Italy, who led the study.

Back in Italy, Vecchiato and his colleagues analyzed the snow samples under clean-room conditions to prevent contamination.

They found PCP chemicals in every sample, with varying chemical concentrations suggesting different capacities for atmospheric transport. Of the 21 chemicals analyzed, three compound families were particularly notable. Salicylates, commonly used as preservatives in cosmetics (including lotions, shampoos, and conditioners) and pharmaceutical products, were the most prevalent, followed by UV filters associated with sunscreens. Fragrances such as musks were also detected.

Most of these substances were dissolved in the snow. The UV filter octocrylene, however, which has been associated with coral reef damage and banned in places like the U.S. Virgin Islands and Palau, was found bound to solid particles within the snow.

The researchers observed an unexpected seasonal variation in the amount of PCPs within the samples: Samples collected later in the summer had about 10 times higher PCP levels than those collected earlier in the season, though the relative proportions of each pollutant within a sample remained consistent.

Seasonal fluctuation suggests that Antarctic summer air circulation plays a role in transporting pollutants from distant sources to the continent’s interior. During summer, oceanic winds blowing inland dominate over winds originating from the polar plateau, which are stronger during the rest of the year. That shift may push pollutants far inland.

“This very different behavior during the season means that [PCPs] are very sensitive to the environmental conditions,” Vecchiato said.

One of the researchers presented the team’s preliminary findings at the European Geosciences Union General Assembly in May, and the scientists have a more comprehensive analysis currently underway, according to Vecchiato.

A Local or Distant Source

Finding organic pollutants in seemingly pristine polar environments isn’t surprising. In the 1960s, scientists found large concentrations of persistent organic pollutants (POPs), including the widely used pesticide DDT (dichlorodiphenyltrichloroethane), in Antarctica. POPs don’t degrade naturally and travel thousands of kilometers through the atmosphere, with some eventually getting trapped in snow and ice. Permanently frozen places such as glaciers and polar regions become natural traps. Starting in the early 2000s, the United Nations’ Stockholm Convention on Persistent Organic Pollutants established international cooperative efforts to eliminate or restrict the production and use of POPs.

Though they might travel by a mechanism similar to that used by persistent organic pollutants, unlike POPs, PCPs “do break down in the environment,” said Alan Kolok, a professor of ecotoxicology at the University of Idaho. However, “if those fragrances are not coming from the [research] stations themselves,” he asked, “where are they coming from?”

To rule out a local origin for the PCP pollutants, researchers analyzed sewage from the Mario Zucchelli research station. The outpost did contribute some pollution, but the relative abundance of each compound in the sewage differed from that found in the snow, suggesting that the PCPs detected in the broader Antarctic environment likely originated from more distant sources.

“My suspicion is that for these types of compounds—personal care products, pharmaceutical products—there must be a local source,” said Ricardo Barra Ríos, an environmental scientist at the Universidad de Concepción in Chile who has analyzed PCP pollution in Antarctic coastal waters related to research stations. “Thousands of people are currently accessing the Antarctic continent, and my conclusion is that wherever we humans go, we bring contaminants.”

Vecchiato disagreed. In a separate study published earlier this year, he and other colleagues found PCPs, including fragrances and UV filters, in the snows of the Svalbard archipelago in the Arctic. In that study, the researchers linked the presence of these compounds to atmospheric patterns that carried pollution from northern Europe and the northwestern coast of Russia.

“Most of these contaminants should have a limited mobility, but actually, we found them in remote regions,” Vecchiato said. “Does that mean that the models are wrong or that our analysis is wrong?” he asked. “No, probably we are missing a piece [of the puzzle], or maybe the use of these contaminants is so huge that we still have a relevant concentration in remote areas, even if they should not be prone to this kind of transport.”

—Javier Barbuzano (@javibar.bsky.social), Science Writer

Citation: Barbuzano, J. (2025), Is your shampoo washing up in Antarctica?, Eos, 106, https://doi.org/10.1029/2025EO250209. Published on 3 June 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.

Frank Marks remembers the Diet Coke can floating in front of his face as the plane pitched violently. After several attempts to grab it, he gave up and focused on avoiding the other debris ricocheting around the cabin. Then an engine flamed out, and the pilots dumped 15,000 pounds (6,800 kilograms) of fuel in a last-ditch effort to climb to relative safety without overheating the three working engines. The flight miraculously landed safely in Barbados a few hours later.

Rather than swearing off flying forever, many of the flight’s passengers were back in the air 2 days later for another chance to chase the storm that very nearly killed them.

Most pilots give storms a wide berth, but those flying NOAA’s two WP-3D Orion aircraft—known as Hurricane Hunters—head right for them. Those flights yield important data about storm structure and intensity that can help protect people on the ground. “There’s only so much you can learn from remote sensing,” said Todd Lane, an atmospheric scientist at the University of Melbourne in Australia who was not involved in the research. So scientists, pilots, and crew keep flying, despite the risks that severe turbulence poses.

New research published in the Bulletin of the American Meteorological Society shows that Marks’s memorable flight through Hurricane Hugo in 1989 was rightly infamous—it ranks as the most turbulent NOAA Hurricane Hunter mission to date. Data from that and other bumpy NOAA Hurricane Hunter flights could make future trips safer.

The Bumpiest of Them All

Josh Wadler, a meteorologist at Embry-Riddle Aeronautical University in Daytona Beach, Fla., had a wild ride aboard a NOAA Hurricane Hunter aircraft in September 2022. He and his colleagues were flying through Hurricane Ian to study how energy was being transferred from the ocean to the atmosphere and, ultimately, into the hurricane. That Hurricane Hunter flight was by far the bumpiest of the 20 or so he’d been on, with extreme turbulence lasting for an unprecedented 10 minutes or so.

When the team finally emerged into smooth air, Wadler and others on board couldn’t help but wonder how their experience stacked up to the infamous 1989 flight through Hurricane Hugo. Being scientists, they decided to throw data at the question. “We’re scientists—let’s try to figure this out,” Wadler said.

Wadler and his colleagues mined in-flight data collected automatically by onboard navigation systems for every NOAA Hurricane Hunter flight into a tropical cyclone from 2004 to 2023. Those data, recorded every second, were already digitized and freely available online. But amassing data from two earlier flights for comparison—through Hurricane Hugo and another notoriously bumpy storm, Hurricane Allen, in 1980—required a bit more finesse. “There’s no record of them online,” Wadler said. “They’re just on tapes.”

Enter the data-wrangling skills of Neal Dorst, a meteorologist with the Hurricane Research Division of NOAA’s Atlantic Oceanographic and Meteorological Laboratory in Miami. “Back in the day we would record the flight-level data on magnetic tapes,” Dorst said. Reels of magnetic tape sit in a room just down the hall from Dorst’s office. He’s digitizing them all and processed the Hurricane Hugo and Hurricane Allen data out of sequence after a special request for this project.

For each NOAA Hurricane Hunter flight of interest, the team analyzed six different aircraft motions: three translational (forward and back, side to side, and up and down) and three rotational (roll, pitch, and yaw). For every second, the team calculated the aircraft’s acceleration and jerk—that is, the rate of change of acceleration in time—in each of those six dimensions.

Because rotational motion depends on position relative to an axis of rotation, the team also considered a passenger’s seat position when determining what acceleration and jerk someone on board would have experienced. “The farther away from the axis of rotation you are, the more you feel,” Wadler said. “You’re going to feel the rotational motions more in the front or back of the plane.”

When the researchers tabulated a “bumpiness index” that took into account both acceleration and jerk, Wadler discovered that his memorable flight through Hurricane Ian in 2022 ranked second to the flight through Hurricane Hugo. That finding wasn’t wholly surprising, Wadler said. “There’s a lot of folklore about that flight.”

That infamous Hurricane Hugo flight pierced the storm just 1,600 feet (500 meters) above the Atlantic Ocean. That left dangerously little airspace for maneuvering and sent the plane directly into a region of the storm known for its extreme winds. (Nowadays, NOAA Hurricane Hunters fly roughly 6 times higher.)

Different Kinds of Bumpy

The in-flight data also corroborated something that Marks and his colleagues aboard the 1989 flight remember well: Their wild ride was characterized by extreme up and down motions. “Within a minute, we went through these huge three updraft/downdraft couplets,” said Marks, a meteorologist who retired last year from the Hurricane Research Division of NOAA’s Atlantic Oceanographic and Meteorological Laboratory. Wadler’s trip through Hurricane Ian, on the other hand, involved strong turbulence directed largely sideways. “The side to side motions were unique,” Wadler said.

Hurricanes Irma (2017), Sam (2021), and Lane (2018) rounded out the top five positions. Wadler and his collaborators found that turbulence tended to be stronger for large storms that went on to weaken in the next few hours. Bumpiness was also most pronounced near the inner edge of a storm’s eyewall and near features known as mesovortexes, which are basically storms within a storm.

Beyond satisfying a personal curiosity, the finding could help make future NOAA Hurricane Hunter flights safer. “We know what to look for on radar when we’re going into a mission,” Wadler said. He hopes to take this new work in the direction of crew performance and cognition. “Is there a threshold of turbulence where humans are bad at making decisions?” he wondered. But instead of taking willing participants up on flights, Wadler plans to do laboratory experiments mimicking turbulence.

—Katherine Kornei (@KatherineKornei), Science Writer

Citation: Kornei, K. (2025), The wildest ride on a Hurricane Hunter aircraft, Eos, 106, https://doi.org/10.1029/2025EO250194. Published on 21 May 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.

Alex Thomson, an algal ecologist with the Scottish Association for Marine Science, had planned to study coastal blooms of microalgae during his 2023 trip to Robert Island in Antarctica. But after arriving, he and his colleagues made a discovery that would change their mission.

Scientists have known for years that ice in the Arctic is teeming with microscopic algae. But aside from a few scattered observations, nobody knew whether such blooms were widespread in Antarctica’s ice caps (an ice cap is a type of gently domed glacier flowing outward in all directions). Thomson and his colleagues decided to collect a few samples from the Robert Island ice cap while they were there.

When they got the samples under a microscope, it was clear that the ice was a bustling hub of algal activity. “As we started to uncover this during the field season, we shifted our focus and took what was happening on the ice cap more seriously,” Thomson said.

In a study published in Nature Communications, the researchers revealed the extent and diversity of algae they found inhabiting the ice. Their findings warn that algae, whose pigments absorb heat from the Sun, may be accelerating the melting of Antarctic ice at a rate greater than previously thought.

“It’s the first paper quantifying that process in Antarctica,” said Alexandre Anesio, an Arctic algae expert at Aarhus University in Denmark who wasn’t involved in the new study.

Widespread Blooms and Unexpected Diversity

Scientists sampled from 198 locations and examined WorldView-2 satellite images from February 2023, which revealed darkened patches of ice indicative of algal blooms. On the basis of their sampling and the satellite images, the scientists estimated that algal blooms covered around 20% of the ice cap’s surface.

The newly discovered algal communities may represent one of the largest photosynthetic habitats in Antarctica. Researchers had previously estimated that all detectable photosynthetic life in Antarctica covered approximately 44 square kilometers. The ice cap algal blooms on Robert Island alone were equivalent to about 6% of that area.

The scientists also found a diverse range of species in their samples. The most prevalent genus of ice algae, Ancylonema, has an elongated “sausage shape and can form in chains,” Thomson said. “We were seeing this huge morphological diversity, loads of forms of Ancylonema that I’d never seen described in any of the literature.”

Genetic analysis revealed that the Antarctic ice cap contains Ancylonema species that are similar to those found in the Arctic, but also others that were distinct. Some genetic lineages appear unique to Antarctica, suggesting that these communities may have evolved in isolation over millions of years.

Dark Pigments Accelerate Antarctic Ice Melt

Thomson was excited by the diversity of algae, but said the finding could have troubling implications.

When a researcher on the team used a backpack device that Thomson said “looks a bit like a piece of Ghostbusters apparatus” to measure how much light reflected off the ice’s surface, they discovered that areas of ice containing algae reflect significantly less light than areas without algae. The purple pigment within Ancylonema, which it uses as sunscreen to protect itself from ultraviolet radiation, absorbs more energy and heats the surrounding ice.

Through modeling, they found that algae can contribute up to around 2% of the total daily melting on the ice cap. Though the figure isn’t as high as it is in Greenland, where dense blooms can increase melt rates of the ice surface by 13%, scientists are concerned that warmer temperatures may allow more algae to grow, which would cause more heat to be absorbed into the ice caps. “That 2% is probably going to look more similar to Greenland” in the future, Anesio said.

Currently, climate models do not account for microorganisms’ contributions to melting. To Anesio and Thomson, studies like this highlight why that needs to change. “This study gives a big preview of what can happen in Antarctica if you start to have warm summers,” Anesio said.

—Andrew Chapman (@andrewchapman.bsky.social), Science Writer

Citation: Chapman, A. (2025), Newly discovered algae may speed melting of Antarctic ice, Eos, 106, https://doi.org/10.1029/2025EO250174. Published on 9 May 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.

Source: Community Science

Communities on small islands are on the front lines of worsening flood risks—not just from severe storms but from persistent tidal flooding events. Scientists estimate that within 15 years, high-tide flood events could triple for two thirds of communities along the East and Gulf Coasts of the United States.

Sea level rise and tidal flooding can vary depending on local land morphology, offshore bathymetry, and wind direction and intensity. To test how a community science partnership might better determine flooding risks, Bertram et al. focused on Little Cumberland Island, Georgia. The community comprises about 40 residences connected by unpaved roads, though no road connects it to the mainland.

In 2021, island residents agreed to allow faculty and students from the College of Coastal Georgia to conduct field research on the island. They asked the researchers to focus on developing a way to predict the frequency and severity of future floods and ultimately provide insight into how to develop more resilient roads.

For the next 2 years, the researchers visited the island every 1–2 months. Each time, an island resident hosted the team for dinner and shared stories about past flooding events and some of their greatest concerns. The scientists shared research updates with the residents, including water pressure recordings in flood-prone areas and comparisons between wind-enhanced high-tide measurements and predicted tidal flooding.

Residents reported that flooding of low-elevation roads has grown more common over time and that this flooding was worse when winds arrived from the northeast. The researchers’ measurements, which supported these observations, allowed the team to determine how wind velocity affects tidal flooding and to predict future flood frequency.

The researchers suggest that grading roadways so they dip downward on the sides, combined with increasing the size of sediment used for the roads from sand to gravel, could be enough to protect the roads until 2030. However, they predict that by 2040, “nuisance flooding” of 30 centimeters or less will double to triple in frequency.

Considering the findings, the researchers suggest that more permanent changes to the roads, such as building a raised wooden bridge, should be implemented within the next decade. They note that though the project was successful at addressing residents’ concerns and incorporating local knowledge, future work could further involve community members in data interpretation and developing recommendations. (Community Science, https://doi.org/10.1029/2023CSJ000058, 2025)

—Sarah Derouin (sarahderouin.com), Science Writer

Citation: Derouin, S. (2025), Flood prediction could boost road resilience off Georgia’s coast, Eos, 106, https://doi.org/10.1029/2025EO250169. Published on 2 May 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.

Boots On the Ground

Seen from above, the dozens of people trekking through the Rwenzori Mountains might have looked something like an ant farm branching across the landscape, said Klaus Thymann. The expedition into the range on the border between Uganda and the Democratic Republic of the Congo included Thymann, an environmental scientist; Heïdi Sevestre, a glaciologist at the Arctic Monitoring and Assessment Programme; guides from the Uganda Wildlife Authority (UWA); and—predominantly—interested community members there to help with logistics.

The group was there in August 2024 to survey ice on the range’s three tallest peaks and to create the first 3D model of the glaciers on Mount Stanley, whose apex, Margherita Peak, is the third highest in Africa at 5,109 meters (16,763 feet).

“It’s really a team work, and a very good one,” said Thymann, founder and director of Project Pressure, a nonprofit organization focused on environmental issues.

Their newly analyzed data confirmed that Mount Speke, the second-highest peak in the range, no longer hosts a glacier (only static ice) and that Mount Baker, the third highest, is practically ice free. The researchers found that the surface area of the Stanley Plateau glacier fell by 29.5% between 2020 and 2024.

“Glaciers worldwide are shrinking or disappearing, so that’s not a surprise,” Thymann said. “I think what is surprising is how rapid it’s going.”

Jim Russell, a climate scientist and geochemist at Brown University who was not involved in the research, has been making expeditions to the Rwenzori Mountains since 2006. He called these glaciers a “canary in a coal mine.”

“The recent retreat is really significant, and it’s illustrating substantial climate change is happening at high elevations,” he said.

Sleeping Bags, Licorice, and Drones

Aside from essentials, such as sleeping bags and licorice (“It’s all about the amount of flavor you can get with the least amount of volume,” Thymann explained), the crew carried an array of equipment, including a generator, fuel and cables for the generator, three drones, and GPS hardware.

“There’s no roads, there’s no helicopters, there’s not even a donkey,” Thymann said. “Everything has to be carried in, so that makes science challenging because the logistics are difficult.” With the weight of equipment and the need to acclimate to the elevation, it’s a 5-day trek from the entrance of Rwenzori Mountains National Park up through tropical, bamboo, and alpine forests to the Stanley Plateau.

Thymann led expeditions to the area in 2012, 2020, and 2022. In 2020, the team captured images of the plateau with consumer drones, then used photogrammetry to create a digital elevation model of the area.

When they returned in 2024, they went one step further. They used a surveying system to determine the precise GPS coordinates of eight points along the plateau, then set up a brightly colored target on each point. When they flew drones over the area to capture more than 850 photos, they could not only create a model but also anchor it to precise GPS coordinates. They also used the points to retroactively anchor the 2020 model. By comparing the two models, they determined the extent of ice loss on the plateau.

Sevestre, the glaciologist, also used ground-penetrating radar to determine the depth of the glaciers. “If you want to know volume, you have to know three dimensions. You have to know the x, the y, and then the z,” Thymann said. “Nobody knew the z, so nobody knew the depth.”

The researchers expect to publish more detailed findings, including glacier volume, in late 2025.

Russell said he was “amazed” the researchers were able to do this work in this remote area. Though there is no standard way of mapping glaciers, he added that the Rwenzori Mountains’ glaciers have historically been mapped simply by tracing the movement of their edges. The Project Pressure team is “not just tracing the lowest elevation of the glacier,” he said. “They’re also able to kind of see the sides, see how that’s shrinking, potentially see it thinning from the top.”

Protecting the Home of Gods

The dwindling of Rwenzori’s ice may be a bellwether of glaciers’ futures worldwide, but closer to home, its effects are already being felt.

The ice on the mountain range is the highest source of water for the River Nile and holds water that millions of Ugandans rely upon. Trekking tourism to Rwenzori Mountains National Park, a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site, also bolsters the local economy.

“This ice supports the people of the communities living around it, 100%,” said Masereka Solomon, a tour guide in Uganda who began working with Thymann in 2012. Solomon has lived in the area for 34 years—his whole life—and has watched the ice retreat firsthand. For him and other Bakonzo people who live in the foothills of the Rwenzori Mountains, the glaciers also hold a deep religious and cultural significance, as they believe that their gods live in the ice atop the mountains.

“We believe if we protect this mountain, if we fight hard to maintain the small ice, or the small glaciers that [remain], our gods will not be homeless,” Solomon said.

Thymann emphasized the role of the dozens of community members during the expeditions, from helping transport equipment up the mountain to spotting the drones and returning regularly to maintain time-lapse cameras. He and the other Project Pressure researchers analyze the data and share the results with UWA and locals.

He added that though the Bakonzo people understand that the retreating ice is caused by climate change, he hopes that this more detailed data can “empower” the community and that sharing these findings widely will raise awareness of Uganda’s shrinking glaciers.

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

Citation: Dieckman, E. (2025), A new 3D map shows precipitous decline of Ugandan glaciers, Eos, 106, https://doi.org/10.1029/2025EO250126. Published on 3 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.

Boots On the Ground

In mid-January, a team of scientists were sailing aboard a research vessel in frigid Antarctic waters. They planned to investigate an unexplored section of the Bellingshausen Sea and the creatures that live there, but were stymied by more sea ice than they expected.

“We found ourselves restricted to a smaller area,” said Patricia Esquete, a marine biologist at the Universidade de Aveiro in Portugal and expedition co–chief scientist. “Instead of Bellingshausen Sea, we were restricted to the Ronne Entrance.” The team made the most of the situation, and their research vessel, Schmidt Ocean Institute’s R/V Falkor (too), settled in to conduct science operations in front of the ice shelf.

While checking satellite images of sea ice extent, they noticed that a crack had formed along the edge of the George VI ice shelf about 30 kilometers from their location. They jotted it down but didn’t worry about any dangers it posed. Such cracks can take weeks or months to fully force a break from the shelf and form an iceberg, Esquete explained.

But when the next batch of satellite images came through a few days later, the team was surprised to see that a 510-square-kilometer (209-square-mile) iceberg had broken off and was drifting along (and occasionally bumping against) the coast of the Antarctic Peninsula. The departure of the Chicago-sized iceberg, A-84, revealed a patch of polar seafloor that had been covered by ice for years, and possibly centuries.

“As soon as we realized that the iceberg had moved on and left that space for us to sample, we immediately decided to go there and see [what] the seafloor looks like under the ice,” Esquete said. When they arrived, they found a thriving ecosystem rivaling those in nutrient-rich open waters.

Luck and Daring

Before A-84 calved, the team was poised to document the biodiversity of a nearby deep-sea ecosystem, collect sediment samples, study underwater ocean dynamics, and create seafloor maps.

“A holy grail for oceanography is not only mapping the entirety of the deep seabed in high resolution in terms of its shape and structure, but also in terms of specifically what lives there and how,” said Dawn Wright, an oceanographer and chief scientist at Environmental Systems Research Institute (Esri) in Redlands, Calif., who was not involved with this expedition.

Sea ice impedes that goal: Research vessels can’t get too close to the ice shelf, and remotely operated vehicles (ROVs) and autonomous underwater vehicles can travel only so far from the ship to explore under the ice.

The procedures involved in securing funding and scheduling a ship can make seagoing research in the Antarctic a slow process, explained Joan Bernhard, a biological oceanographer at Woods Hole Oceanographic Institution in Massachusetts. Planning an expedition like the one in January can take years or even decades, with few exceptions.

Some expeditions have been able to mobilize when seafloor is newly exposed. After Larsen C calved in 2017, for example, research vessels arrived in the area about a year later—much faster than average. Changes at the surface take time to affect the seafloor, but even with such a quick response time, researchers still missed the opportunity to establish a precalving baseline.

After most calvings, “any newly exposed seafloor will have been subject to open-water conditions for years; currents could import alien species potentially impactful to indigenous taxa,” said Bernhard, who was not involved with the Falkor (too) expedition.

Iceberg A-84 calved on 13 January. Falkor (too) reached the newly exposed seafloor just 12 days later.

After relocating, the researchers conducted the same suite of science observations they had originally planned, just in the newly exposed location. Thanks to the quick pivot, the team was able to observe the area as if it were still covered by the ice—an “incredibly rare” opportunity, Bernhard said.

“In my view, nowhere has serendipity in ocean science proved more critical,” Wright said of the expedition. Operating in those conditions is hard enough, and it’s even tougher to be in the right place at the right time, she added.

Esquete acknowledged the expedition’s fortune. “Good luck played a huge role. We cannot deny that,” she said. “But there’s also value in daring to explore the unexplored.” The team would have missed the opportunity had they not already been exploring one of the most remote parts of the world.

Thriving Beneath the Ice

The researchers collected sediment samples, used lidar to create bathymetric maps, and studied the water column and ocean currents. They are still analyzing those data. They also deployed the ROV SuBastian to document the biodiversity of the deep sea and found a thriving ecosystem spanning the trophic web: corals, sponges, invertebrates, cephalopods, king crabs, and krill, as well as a few unknown species.

“I was excited to see what appeared to be meter-tall sponges, ‘giant’ pycnogonids (sea spiders), and large ophiuroids (brittle stars), all similar to those known from the McMurdo Sound region,” Bernhard said.

“What surprised me was the sheer variety of organisms that were found, as well as the huge sizes of some of the deep-sea sponges that had apparently been growing for hundreds of years under such harsh Antarctic conditions,” Wright said.

What’s more, the team found several species that filled discrete ecological niches, which suggested that the ice-covered ecosystem received a steady, high-level influx of nutrients and may have been there for a while, Esquete said.

“Basically, we found the same type of ecosystems that you can expect in that area of the Bellingshausen Sea,” Esquete said. But unlike the other areas the team studied, this ecosystem thrived “in an area that’s been permanently covered by ice for probably centuries.”

That in itself was surprising, she said. Most deep-sea ecosystems that aren’t covered by thick ice receive nutrients that trickle down from photosynthetic organisms near the surface. Scientists think that nutrients carried on deep-sea currents supply nutrients to benthic ecosystems where ice prevents top-down nutrient delivery.

“I was mildly surprised by the plethora of sea anemones on a boulder adjacent to a barrel sponge because all are filter feeders,” Bernhard said. “Such abundance implies currents are strong enough to transport sufficient organic matter to this area.”

A Future Without Ice

The Falkor (too) researchers returned to the mainland after weeks studying the newly discovered Bellingshausen habitat. They already hope for a return trip to investigate how that patch of seafloor changes now that its icy cover has drifted off. Nutrients trickling down from photosynthetic algae might now be available, but the ecosystem has already adapted to and thrived on a lower nutrient supply.

“Open-water conditions may imperil these ecosystems,” Bernhard said. “More settlement of organics to the seafloor…could cause an ecological imbalance.”

As climate change melts Antarctic ice, this ecosystem could be a bellwether for changes across polar ecosystems.

“The accelerating loss of polar ice that protects these ecosystems, including channeling of nutrient-rich currents to them, does not bode well for their vitality,” Wright said. “But there is so much that we just don’t know. The oceanographic community will be watching the results of this expedition as they become available with intense interest. It has direct bearing on the overall health of the planet.”

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

Citation: Cartier, K. M. S. (2025), Thriving Antarctic ecosystem revealed by a departing iceberg, Eos, 106, https://doi.org/10.1029/2025EO250124. Published on 31 March 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.

The Northeast Greenland Ice Stream is a relatively fast-moving slice of ice. It’s Greenland’s largest ice stream, a frozen tributary that transports roughly 12% of the island’s annual ice discharge into the North Atlantic. That makes it a considerable contributor to sea level rise. But so far, simulations of ice discharge haven’t matched the ice stream’s actual movement. The ice is flowing faster than anticipated.

Seismologists recently made an accidental discovery that may explain the gap. In a new study published in Science, the team detailed how small shifts in the ice are having a big impact on glaciologists’ understanding of ice stream flows.

Quakes in Honey

The results came from the East Greenland Ice-Core Project (EastGRIP), which recently drilled a 2,700-meter borehole directly through the ice stream. On the last day of the 2022 field season, Andreas Fichtner and a colleague were at EastGRIP to set off some explosions, hoping to use the resulting seismic waves to create “an ultrasound image of the ice.” Fichtner is a seismologist at ETH Zürich and lead author of the new study.

The team used a 1,500-meter-long fiber-optic cable to record the waves. They manually unspooled the cable into the borehole, then left to set off their explosives.

Their experiment worked as planned, providing images of the ice stream’s interior. While the cable was installed for 14 hours, however, it recorded other, unexpected seismic signals.

“In between those explosions, we expected nothing to happen,” Fichtner explained. Glaciers are assumed to move like a viscous liquid, a thick honey sliding downhill. And “in honey, you don’t expect things to break,” Fichtner said. But when he and his colleagues looked at the data from the cable, they saw five clear seismic events.

Fichtner started analyzing the data that night, initially thinking the five signals were “rubbish,” just noise. But a closer look showed they were cascades of quakes, occurring when a series of microcracks ruptured the ice as it lurched slightly downhill.

A tiny crack would form, radiating small seismic waves. A few milliseconds later, another rupture would be triggered a dozen or so meters higher in the ice. Then another. And another.

Instead of flowing like honey, the ice was sticking and slipping in small bursts.

The cascades were complex, but two of the five were remarkably similar in depth and duration. “It’s like two people accidentally building the same sequence of dominoes,” Fichtner said of the discovery.

Ash on Ice

Surface seismometers hadn’t recorded these tiny ruptures before. The seismic cascades originated deep in the ice and appeared to stop roughly 890 meters below the surface, a depth immediately familiar to Fichtner’s colleagues with expertise in the local ice cores. The ice at 890 meters is roughly 7,600 years old. That’s when Oregon’s Mount Mazama exploded, creating Crater Lake, now part of Crater Lake National Park. The eruption distributed volcanic ash and glass called tephra over parts of North America and Greenland.

Tephra affects the way ice crystals form, creating a structurally weaker layer. Instead of continuing to cascade vertically to the surface, seismic waves triggered short bursts of horizontal movement along the tephra layer instead.

The researchers found that the cascades had originated at depths in the ice known to contain volcanic sulfate, which also creates structurally weak ice. These sulfate layers can also be pinned to specific eruptions. The finding shows how these centimeter-scale features can affect an ice sheet across kilometers, Fichtner said, and further demonstrates the effect of volcanic remnants on Greenland’s ice flow.

We All Scream for Ice Streams

“It changes the way we think about how ice moves,” said Marianne Karplus, a seismologist and geophysicist at the University of Texas at El Paso, about the results. The research team ruled out several possible sources for the seismic signals, she said, such as waves reflecting off the end of the cable or cracks caused by a change in ice crystal orientation. “It seems like they came up with a very interesting and believable explanation.”

Sridhar Anandakrishnan, a glaciologist at Pennsylvania State University, agreed, noting the results “move us towards a more realistic description of glacier flow.” Models often treat the entire ice sheet as one homogenous block for simplicity’s sake, but “the strain gets concentrated at these layers of the volcanic impurities,” he said.

Anandakrishnan said he’s curious about whether the borehole’s disruption affected the results. But overall, he said, “I think this is really a fantastic result.”

Future ice sheet simulations can incorporate major volcanic events to better understand the movement of flows. That could lead to better predictions of sea level rise.

“We need very accurate representations of the ice if we’re going to make projections for the next 50 or 100 years,” Anandakrishnan said. These new results make it clear: “We don’t know everything that we need to know.”

—J. Besl (@J_Besl), Science Writer

Citation: Besl, J. (2025), Tiny icequakes ripple through Greenland’s largest ice stream, Eos, 106, https://doi.org/10.1029/2025EO250085. Published on 5 March 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.

This is an authorized translation of an Eos article. Esta es una traducción al español autorizada de un artículo de Eos.

Escondidos en montañas remotas, los lagos alpinos parecen prístinos, pero sus sedimentos dicen lo contrario. La arcilla y la arena en el fondo de estos lagos contiene cientos de años de historia, contada por los genes de los pequeños organismos flotantes que los habitaban.

Las huellas de la humanidad llegan a estas grandes altitudes, pero exactamente cómo hemos afectado la vida en los lagos sigue siendo incierto. Sin embargo, al examinar el material genético enterrado en el fondo de los lagos, los investigadores descubrieron que las poblaciones de zooplancton de diversos lagos de las Montañas Rocosas han cambiado en los últimos cientos de años, y que la culpa la tienen las truchas no nativas.

Después de que las truchas fueran introducidas, “vemos cambios en la [diversidad de la] comunidad, pasando de zooplancton grande a zooplancton pequeño”, explicó la primera autora Jordan Von Eggers, candidata a doctora en ecología por la Universidad de Wyoming en Laramie. Una menor diversidad puede hacer que las comunidades planctónicas sean menos resilientes al cambio, explicó, y dicha resiliencia tiene consecuencias de gran alcance, dado que estos microorganismos desempeñan un papel importante en el mantenimiento de la salud ecosistémica del lago.

Von Eggers y sus colegas presentarán su investigación el 13 de diciembre en la Reunión Anual del 2024 de la AGU en Washington, D. C.

Hallazgos Preservados en Capas de Lodo

Los lagos de gran altitud son entornos ideales para estudiar cómo las actividades humanas pueden afectar los ecosistemas lacustres. Muchos lagos alpinos carecen de peces por naturaleza, se calientan con facilidad cuando el aire aumenta de temperatura y sus algas y plantas responden rápidamente a las fluctuaciones de contaminación por nitrógeno. Alaltarles oxígeno, sus aguas frías y profundas son perfectas para preservar el frágil material genético. El lodo se acumula tan lentamente que 30 centímetros (12 pulgadas) de sedimento pueden registrar alrededor de 500 años de historia.

El equipo aprovechó estas condiciones en siete lagos de la Cordillera Wind River y la Cordillera Snowy en Wyoming. Acompañados por tres llamas para transportar el equipo, recorrieron miles de metros para recolectar muestras de núcleos de sedimento. Los investigadores llevaron las muestras al laboratorio para extraer y analizar el ADN.

Esos análisis genéticos revelaron que el principal factor que causaba los cambios en la diversidad del zooplancton no era el incremento de la temperatura del aire o la contaminación por nitrógeno, sino los peces no nativos. A inicios de los 1900’s, pescadores recreativos trajeron de todo el país truchas arcoíris, truchas degolladas y truchas de arroyo, y las introdujeron en los lagos de Wyoming para pesca deportiva.

Los cambios en el ADN sedimentario mostraron que los nuevos peces se alimentaban preferentemente de copépodos de mayor tamaño, los cuales habían sido los dominantes, permitiendo que prosperara el zooplancton de cuerpo pequeño, como la Daphnia.

Von Eggers dijo que estaba sorprendida por el efecto inmediato y consistente de las truchas introducidas en todos los lagos que ella y sus colegas estudiaron. “[Había] este gran copépodo rojo en cada lago en el pasado, y justo cuando los peces se introdujeron, todo cambió”, afirmó.

Es raro ver que el AND sedimentario se utilice de esta manera, dijo Bianca De Sanctis, investigadora posdoctoral en ecología y biología evolutiva de la Universidad de California, Santa Cruz, quien no estuvo involucrada en el estudio. “Es uno de los primeros usos del ADN sedimentario con fines de conservación”, explicó. “No es frecuente que tengamos esto [en el campo]”.

El aprovechamiento de estos conocimientos genéticos ofrece una perspectiva histórica de cómo los patrones de biodiversidad y la salud de los lagos se ven afectados por la intervención humana, de acuerdo con el equipo de investigación. Ellos esperan que sus resultados ayuden a orientar las estrategias de gestión para proteger la variedad de organismos que viven en los lagos más vulnerables y alrededor de ellos. (El Departamento de Caza y Pesca de Wyoming sigue poblando los lagos con truchas).

“Estos lagos de montaña y sus alrededores son sistemas únicos donde sólo ciertas especies pueden vivir”, Von Eggers explicó. “Aprender los impactos de las especies invasoras y lo que pueden hacer es una gran lección”.

—Jasmin Galvan (@jasmin-galvan.bsky.social), Escritora de ciencia

This translation by Nidia Tobon-Velazquez (@ntobon31) was made possible by a partnership with Planeteando and GeoLatinas. Esta traducción fue posible gracias a una asociación con Planeteando y GeoLatinas.

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.

Scientific ocean drilling (SciOD) aboard the riserless drill ship JOIDES Resolution (JR) provided unique opportunities for thousands of scientists and laid career foundations for many early-career researchers (ECRs). Hundreds of JR alumni have continued sailing throughout their careers, thriving in the fast-paced environment, conducting science at sea, and working with collaborators from all over the world.

On 30 September 2024, the contract between the National Science Foundation (NSF) and SEA1 Offshore (the private company that owns the JR) came to an end, with no plan in place for a replacement vessel.

Expedition 403 concluded the scientific work of the JR and was the second-to-last expedition of the International Ocean Discovery Program (IODP), “an international marine research collaboration that explores Earth’s history and dynamics using ocean-going research platforms to recover data recorded in seafloor sediments and rocks and to monitor subseafloor environments.”

The JR drilled its last cores along the western margin of the Svalbard archipelago. The selected sites sit along a major ocean gateway modulating the flow of currents between the North Atlantic and Arctic Oceans. Questions regarding changes in meridional overturning circulation, the climatic evolution of Northern Hemisphere ice sheets, and so much more can now be more fully addressed with 5.5 kilometers of newly acquired marine sediment cores.

Sailing as an ECR on the last expedition of the JR came with heartbreak and longing alongside the excitement. Aside from the cutting-edge science that can be conducted with the newly cored sediments, Expedition 403 was incredibly special to the three scientist-authors on board, as it was led by two women, it contained a very diverse and international group of scientists, and the majority of the U.S.-based science party were ECRs and women.

Here three ECR women share their personal accounts of sailing on the last voyage of the JR. These interviews have been edited for length and clarity.

Who We Are and Who We Were on Board the JR

Adriane Lam: My research lies in three main arenas: paleontology, paleoceanography, and science communication (SciComm). I use fossil marine plankton to investigate evolutionary processes through geologic time, and the chemical signatures of those same fossils help me reconstruct the behavior of surface currents across analogue warm periods. Within SciComm, my colleagues and I study how to best conduct outreach on social media platforms.

However, on Expedition 403, the three of us sailed as sedimentologists.

Gryphen Goss: I am not a sedimentologist—I’m more of an isotope geochemist—but as Adriane said, on Expedition 403 I sailed as a sedimentologist. This role provided me with a whole new skill set (characterizing sediment deposited over millions of years) and a new perspective on marine glacial environments.

For 2 months, each day on the JR involved 12 hours of sediment analysis, one 10-meter section at a time. Analysis included precise identification of lithology (clay, silt, silty clay, sandy mud), color (10R 4/1—know your Munsell color chart), boundary contacts (curved), clasts (how many and what size), and much more. After analyzing a few thousand meters of sediment, one earns the badge “Professional.”

Thankfully, after the day shift and midnight dinner, I could escape to the gym to hangboard or sip tea on the bow.

Nicole Greco: Although I have since transitioned my work more toward science outreach and communication, my background is in glacial sedimentology, where I used particle size as a proxy for meltwater events and bottom current speeds. Although I joined the expedition with experience describing and sampling sediment cores, the pace and number of cores far surpassed anything I had previously done.

Sailing as ECRs

Adriane: Expedition 403 was my third expedition on the JR. I first sailed on Expedition 371 to the Tasman Sea when I was a second-year Ph.D. student in 2017 and participated as a shore-based scientist on Expedition 393 in the southwest Atlantic when I was a postdoc in 2022. Sailing during three phases of my career was amazing, as I became more and more independent and confident during each expedition.

Sailing with IODP literally launched my career, as I was able to grow an international team of colleagues quickly and branched out into other research avenues. Today, I get to train my undergraduate and graduate students to conduct research on SciOD data and samples, and some have even participated on seagoing expeditions and opportunities!

Gryphen: My involvement with the IODP began in August 2021, when I started my Ph.D. My supervisor, Dr. Alan Rooney, handed me more than a hundred sediment samples collected from two sites drilled in the North Atlantic and said “get to work.” After completing my first project investigating the regolith hypothesis using radiogenic isotopes, I requested samples from the Bremen IODP core repository from the Scotia Sea in the Southern Ocean to study how ice sheets in opposing hemispheres evolved at the same time.

As someone who is very much a field scientist, I was itching to do fieldwork and was finally fortunate enough to sail for the first time on Expedition 403.

Sailing as an early-career scientist seemed somewhat counterproductive, however. On one hand, I learned the intricacies of working both on the JR and within the realm of SciOD and connected with incredibly inspirational senior scientists. But at the same time, those skills won’t be fully utilized due to the program being terminated.

Nonetheless, like many who have sailed on the JR, my experience was truly addictive. I would like to return to the same cabin—upper ’tween 4-14—and characterize sediment all day, but unlike those who have sailed in the past, my fellow 403ers and I will not get that chance.

Nicole: Although my involvement with the IODP began in 2019 at the start of my Ph.D., Expedition 403 was my first time sailing. In early 2020, I had secured funding to travel to the Oregon State University Marine and Geology Repository to collect sediment samples from Antarctic cores, an opportunity that I would not get to complete until years later due to the pandemic. This delay resulted in relying on published data and coding throughout the majority of my Ph.D., which was an amazing learning opportunity but not the field or lab work I had envisioned.

Sailing on Expedition 403 was my first opportunity for fieldwork and began less than a month after my graduation. I was driving to my grandparents’ house in south Florida when I received the news that I was invited to sail and was immediately overwhelmed with tears of excitement as I knew I was finally going to step into the shoes that some of my role models, including my graduate adviser, John Jaeger, had filled on past expeditions.

Prior to Sailing

Nicole: As excited as I was to sail, I became so nervous prior to leaving for Amsterdam (our expedition’s departure point) that I almost considered backing out. Life seemed incredibly hectic at the time, having just graduated and knowing I was moving from Florida to California just weeks after returning from the expedition.

My partner convinced me I would forever regret not taking the leap, and I’m so glad I listened to him. As soon as I arrived at the airport and met up with my friend and shipmate Lindsey Monito, I could not have been more excited to get to the JR.

Gryphen: As someone who thoroughly enjoys physically collecting data to then process and analyze, I was very excited to sail into the Arctic. The idea of working 12-hour shifts while possibly seasick, however, wore on me in the days leading up to the expedition. In the end, the feelings of worry were far from necessary. There was no worry, just blissful excitement!

Adriane: I always get super nervous before an expedition, but this was the first expedition I participated in after being diagnosed with depression and anxiety. Being on medication to help manage both conditions was a game changer for me. The over-the-top presailing anxiety was minimal, and as such, excitement about the experience was at the forefront! I also knew this expedition would be heartbreaking, being the last.

Life Aboard the Final Expedition of the JR

Gryphen: The first challenge while sailing, and sailing on the JR specifically, is adjusting to 12-hour shifts and locking in a routine. For me, the gym was truly a lifesaver after midnight dinner. Sailing in the Arctic in 24-hour sunlight made this routine much more manageable.

Getting accustomed to wearing the same two to three outfits every day for 60 days and the slight unpleasantness of the desalinated water from the shower and sink were also a bit of a challenge.

Adriane: The main challenges for me while at sea are always getting to know everyone else (I’m an introvert) and fighting the urge to run to my room after shift instead of socializing.

But these weren’t a huge deal on Expedition 403, as the team was AMAZING and I quickly became close friends with a lot of the other scientists! After friendships were formed, the biggest challenge was trying to not have too much fun so I could get my work done.

Nicole: If you ever wanted to conduct a social experiment to see 25 scientists slowly revert to childlike behavior over a 2-month period, the JR would be a great laboratory. If you’ve had the pleasure of sailing on an expedition, you know how mundane your days can become. No matter how much you love looking at gray mud or small wiggles of data on a screen, it’s difficult to find ways to break up each shift.

The excitement of whales, the midnight Sun, rainbows, sea ice, a new dessert in the mess hall, having enough data to download a new playlist, or an unexpected dance party—any of these incidents was enough to make us all jump up and down like we’d never experienced them before.

The Last Cores

Adriane: The day the JR drilled its last sediment core was honestly the worst day I’ve experienced while at sea. This was the last time the techs would work together to bring a core on deck, the last time the roughnecks would work the drill string, the last time the driller would be in the doghouse.

I outlined my feelings during the last day of coring in a blog entry.

Gryphen: As the final sections of cores were brought aboard the JR, the overall atmosphere on the ship drastically shifted. Reality hit us like a drifting iceberg and the realization that 40+ years of scientific ocean drilling, science that shaped and molded our understanding of the Earth through time, was coming to a cold, hard end at 79°N.

What I found most unexpected was the emotions felt not just by the scientists but by the crew. I was so unaware of the community and relationships that came with being on the JR. Crew members that spent 6 months of every year together aboard the JR, truly a tight-knit family, were now being pulled apart by the expiration of a long-standing contract.

Nicole: There were only two times I cried while on the JR: when I was seasick in the North Sea and thought I might not survive the transit and watching the marine technicians hug after carrying in the final core to the onboard lab. Although it was impossible for the scientists to understand the emotions of the techs and crew—we were only present for a fraction of the time that they spent on board—the day was somber for everyone involved, and it felt like one big family mourning the loss of their home.

What the JOIDES Resolution and SciOD Mean to Us

Gryphen: The mission of the IODP itself—the decades of sheer determination required to explore the world’s oceans every month of every year, to collect kilometers of sediment simply to aid in our understanding of the Earth system—is in itself incredibly motivating.

The program has provided past and future generations with unlimited research potential through repositories filled to the brim with samples that can be delivered to your door. The IODP has made a once-expensive and relatively inaccessible sample collection accessible to any scientist from anywhere.

Nicole: I’ll never forget the day I received the invitation to sail on Expedition 403. It was a once-in-a-lifetime opportunity.

As a glacial sedimentologist, I rely on marine sediment cores as the primary source for reconstructing glacial cyclicity and past climate in polar regions. Collecting new cores is crucial because legacy sediment cores from previous Arctic expeditions contain little to no material spanning the most important climatic periods (warm periods that are analogues to today’s warming scenarios) due to destructive analytical methods and/or degradation with age.

Past ice sheets and the climatic conditions under which they existed can provide a vast amount of information that can be used to make predictions about the future of icy regions under a warming climate. Additionally, due to the danger and remoteness of glacial regions, it is difficult and incredibly expensive to collect near-ice measurements that can tell us about the current stability of ice sheets.

Professional and scientific opportunities provided by the JR will be missed; there are many regions around the globe that have yet to be explored and have the potential to hold key information on climate transitions and glacial changes throughout time, emphasizing the need for scientific ocean drilling to continue.

Adriane: Scientific ocean drilling meant, and still means, everything to my career. I mourn the loss of the IODP for the next generations of ocean scientists, who will never get the opportunity to sail on such an amazing ship.

It is mind-blowing that the United States, which has classified climate change as a national security threat, pulled funding from the single program that has obtained data that are integral for understanding how Earth systems processes can change and operate under conditions of increased atmospheric carbon dioxide. These data can help identify regions that will be most affected by climate change in the future. The decision to not renew the contract between NSF and SEA1 Offshore is the most disheartening and shortsighted decision made by any U.S. funding agency.

The loss of the program is a huge loss for the United States, not just the science community.

Author Information

Adriane Lam (alam@binghamton.edu), Binghamton University, Binghamton, N.Y.; also at Time Scavengers; Gryphen Goss, Yale University, New Haven, Conn.; and Nicole Greco, Arctic Data Center and Learning Hub, National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara

Citation: Lam, A., G. Goss, and N. Greco (2025), Expedition 403: Sailing the last expedition of the JOIDES Resolution, Eos, 106, https://doi.org/10.1029/2025EO250080. Published on 28 February 2025.

This article does not represent the opinion of AGU, Eos, or any of its affiliates. It is solely the opinion of the author(s).

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.

A translation of this article was made possible by a partnership with Planeteando. Una traducción de este artículo fue posible gracias a una asociación con Planeteando.

Tucked away in remote mountains, alpine lakes appear pristine—but their sediments say otherwise. Trapped in the silt and sand at the bottom of these lakes are hundreds of years of history, as told by the genes of the small floating organisms that used to call the lakes home.

Humanity’s fingerprints reach these high altitudes, but exactly how we’ve affected life in the lakes has remained unclear. By examining the genetic material buried in lake bed sediments, however, researchers found that zooplankton populations in several Rocky Mountain lakes have shifted over the past few hundred years, and non-native trout are to blame.

After trout are introduced, “we see changes in the [diversity of the] community from large zooplankton to small zooplankton,” said first author Jordan Von Eggers, a Ph.D. candidate at the University of Wyoming in Laramie studying ecology. Lower diversity can make planktonic communities less resilient to change, she said, and such resilience has far-reaching consequences, as these microorganisms play a significant role in maintaining the health of the lake ecosystem.

Von Eggers and her colleagues will present their research on 13 December at AGU’s Annual Meeting 2024 in Washington, D.C.

Insights Preserved in Layers of Mud

High-altitude lakes are ideal settings to study how human activities can affect lake ecosystems. Many alpine lakes are naturally fishless, they heat up easily when the air warms, and their algae and plant life respond quickly to pulses of nitrogen pollution. Lacking oxygen, their cold, still deep water is perfect for preserving fragile genetic material. Mud accumulates so slowly that 30 centimeters (12 inches) of sediment can record around 500 years of history.

The team took advantage of these conditions at seven lakes in the Wind River Range and Snowy Range in Wyoming. Joined by three llamas to tote equipment, they trekked up thousands of meters to collect sediment core samples. The researchers then brought the samples back to the lab for DNA extraction and analysis.

That genetic analysis revealed that the biggest factor driving changes in zooplankton diversity was not rising air temperatures or nitrogen pollution, but non-native fish. In the early 1900s, recreational fishers brought rainbow trout, cutthroat trout, and brook trout from all over the country and introduced them to the Wyoming lakes for sport fishing.

Changes in the sedimentary DNA showed that the new fish preferentially preyed on larger copepods, which had been dominant, allowing small-bodied zooplankton such as Daphnia to thrive.

Von Eggers said she was surprised by the immediate and consistent effect of the introduced trout across all the lakes she and her colleagues studied. “[There is] this big red copepod in every single lake in the past, and right when fish are introduced, everything changes,” she said.

It is rare to see sedimentary DNA being used in this way, said Bianca De Sanctis, a postdoctoral researcher in ecology and evolutionary biology at the University of California, Santa Cruz, who was not involved with the study. “It’s one of the first uses of sedimentary DNA for conservation purposes,” she said. “It’s infrequent that we get that [in the field].”

Harnessing these genetic insights provides a historical perspective on how biodiversity patterns and lake health are affected by human intervention, according to the research team. They hope their results will help guide management strategies to protect the variety of organisms that live in and around more vulnerable lakes. (The Wyoming Game and Fish Department continues to stock the lakes with trout.)

“These mountain lakes and the surrounding area are unique systems where only certain species can live,” Von Eggers said. “Learning impacts of invasive species and what they can do is a big takeaway.”

—Jasmin Galvan (@jasmin-galvan.bsky.social), Science Writer

Citation: Galvan, J. (2024), DNA in lake sediment reveals the impact of introduced fish, Eos, 105, https://doi.org/10.1029/2024EO240573. Published on 13 December 2024.

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.

Humans plan to return to the Moon later this decade and will do so with a clear goal in mind: long-term lunar habitation. One outcome of that ambitious goal is unintended alteration of the lunar environment, including its thin atmosphere.

When humans touch down on the Moon, particularly in SpaceX’s giant new Starship lander that NASA has contracted for its Artemis program, they will kick a substantial amount of dust into the lunar sky, temporarily thickening the Moon’s atmosphere. Rosemary Killen, a planetary scientist at NASA’s Goddard Space Flight Center in Maryland, and her colleagues have investigated how ongoing lunar activity (not just launching and landing) will also affect the surrounding environment.

Killen’s team found that landing, exploring, and even breathing on the Moon can alter the lunar atmosphere, creating problems for humans and technology on the surface and making key science goals harder to achieve.

Kicking Up Trouble

The Moon is covered in fine dust, or regolith, which formed as a result of countless impacts to the lunar surface over billions of years. The Moon also has a thin atmosphere, its exosphere, with a density of about 100 molecules per cubic centimeter at the surface. The lunar exosphere is thought to originate from powdery regolith being kicked up by impacts and the solar wind.

Compared with the natural processes that gently loft regolith into the exosphere, a Starship landing will be more akin to, well, a rocket launching powder off the Moon’s surface.

Killen estimated that in areas surrounding some human activities on the Moon, the number of atoms in the exosphere could increase 100,000 times compared with what it is now and extend upward in a column of about 80 kilometers. These atoms would then spread out several kilometers over the lunar surface.

“Even after Starship lands on the Moon and the initial plume dissipates, Starship itself [will continue] to outgas,” Killen explained. Examples of outgassing include the evaporation of water or other moisture on the spacecraft’s exterior, evaporation of water from astronauts’ backpacks, and the release of air from airlocks. Regolith kicked up from mining and construction activities will also alter the thin exosphere.

Ultimately, Killen said, human activities might create temporary atmospheres on the Moon. “You [might] have a localized atmosphere around the astronaut, Starship, the rovers,” said Killen, who presented her research on 11 December at AGU’s Annual Meeting 2024 in Washington, D.C.

The creation of these atmospheres will likely present some problems for astronauts and scientists.

One problem is that evaporated water could settle in regions of the Moon as ice. Some of these regions, such as the Moon’s permanently shadowed craters, are where scientists hope to identify and collect pristine samples of ice that have been on the Moon for billions of years. These lunar ice cores could give scientists valuable insight into the origin of water on the Moon—and on Earth.

Water inadvertently introduced by human activity may contaminate the samples. “We’re going to find water,” said Killen, “and it’s going to be us.”

Another issue created by temporary atmospheres is that they could hamper the function of electronics on the Moon. This impediment would complicate the establishment of infrastructure necessary for long-term habitation and would even raise health concerns for astronauts. “It’s a real problem,” said Killen.

“We’re Going to Be Adding Noise to the Background”

If not replenished, atoms introduced to the exosphere quickly fall to the surface. “The lifetime is 6 minutes on average,” said Killen. “But of course the problem is if people stay there.”

These atoms would form what’s called a collisional atmosphere, so named because it is dense enough for atoms to bump into each other.

“One thing we’re really concerned about is that the dust kicked up by rovers and whatnot is going to be charged, so you get what’s called a dusty plasma,” said Killen. “That is going to be extremely toxic to people if it gets into their lungs. It’s like miners who got black lung disease.”

That same dust could also pose problems for machinery. “It can temporarily or permanently disrupt your electronics,” said Killen.

Even when atmospheric particles fall to the surface, they will likely create problems. Any liquid water will stick to the surface of the Moon, but when heated by the Sun, it could be evaporated and transported over the lunar surface, likely settling in cold regions at the poles.

This process “will increase the water in the permanently shadowed regions,” said Killen. “We need to measure the lunar ice before we start adding water from human activities because we’re going to make it very difficult to figure out lunar history.”

Phil Metzger, a planetary physicist at the University of Central Florida who was not involved in the research, agreed that this contamination could make scientific study of the Moon difficult. “If you are continuously generating volatiles at your landing site, it could occur at a sufficiently high density that it prevents you from measuring natural processes on the Moon,” he said.

“The mass of gas that will be blown into the lunar environment by one Starship landing is about 10 times the mass of the entire global atmosphere on the Moon,” he continued. “That’s just from one landing. We want to solve the science as quickly as we can because it’s inevitable that we’re going to be adding noise to the background.”

Lunar Conservation Area

Human activity has already altered the lunar landscape, and introducing change to the lunar exosphere is likely inevitable, Killen admitted.

“Everything is going to outgas,” she said. “The astronauts have to be cooled, and the most obvious way of doing that is water cooling. They need a habitat filled with oxygen and nitrogen, and every time you open the airlocks, some of that is going to escape.”

One suggested way to mitigate the effects of outgassing is to create a lunar conservation area, protected for scientific study. “One proposal is to designate the north pole as a keep-out zone for human activity, except for scientific investigations,” said Killen. “That way you’d have a better chance of determining the history of the Earth-Moon system.”

First, however, “we’re working on understanding the effects” of outgassing from lunar activities, Killen said. Scientists’ second priority is “mitigating the effects for people and instruments. That’s the next step.”

—Jonathan O’Callaghan, Science Writer

Citation: O’Callaghan, J. (2024), Human activities might create temporary atmospheres on the Moon, Eos, 105, https://doi.org/10.1029/2024EO240532. Published on 11 December 2024.

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.

Scientists at the helms of two big climate projects are vying for millions of dollars in NASA funding. One project aims to study tropical forests. The other is focused on research in drylands.

The scientific community has until 5 November to provide feedback on proposals describing each research direction. Early next year, NASA will select one, neither, or elements of both projects to be carried out over the next 6 to 9 years.

Both proposals are “fantastic,” said atmospheric scientist Paul Palmer from the University of Edinburgh, who is not involved in either project. “They’re very complementary, which is going to make them difficult to choose between.”

NASA’s terrestrial ecology program funds field campaigns in which researchers tackle questions about how Earth’s terrestrial ecosystems interact with the atmosphere and hydrosphere and the roles they play in the planet’s biogeochemical cycles.

With a budget of around $100 million and contributions from more than 1,000 scientists, the current campaign—the Arctic Boreal Vulnerability Experiment, or ABoVE—is among NASA’s largest field campaigns to date.

“We really do think [a budget] in that tune or even higher” is necessary for the next campaign to answer fundamental questions about climate change in a timely manner, said environmental scientist Elsa Ordway from the University of California, Los Angeles. She is leading the proposed project focused on the tropics, called the PAN Tropical Investigation of Biogeochemistry and Ecological Adaptation (PANGEA).

Wet and Wild

Tropical forests hold more than 40% of the planet’s biomass, but many are not as lush as they once were. Some fear their degradation could have drastic implications for the world’s carbon budget, biodiversity, and the people who live in these ecosystems. Despite their importance, these regions have “major data gaps,” Ordway said. Data on how the African tropics absorb and emit greenhouse gases are particularly scarce.

Ordway and her colleagues hope to use satellites, airborne instruments, and ground-based measurements to compare how climate change is affecting tropical forests in Africa and the Americas, including their abilities to store carbon. Previous work suggested the two regions react differently to environmental stresses, but both are in danger of switching from carbon sinks to carbon sources.

Unraveling these mysteries is “fundamental, because the uncertainties are very large,” said atmospheric scientist Benjamin Gaubert from the National Center for Atmospheric Research, who is not involved in either of the proposed projects.

PANGEA also proposes to train a future generation of African scientists. “There’s an immense amount of talent and potential on that continent,” Ordway said.

Dry Doesn’t Mean Dead

Many people picture drylands as “blowing sand dunes,” said biogeochemist Sasha Reed from the U.S. Geological Survey, who is leading the proposed Adaptation and Response in Drylands (ARID) project. But drylands are home to about a third of the world’s population, provide 60% of humanity’s food, and hold 52% of Earth’s soil carbon.

Climate models are not well suited to drylands, partly because rainfall changes these landscapes so dramatically, often after a lag of days to weeks. With droughts and fires already hitting this biome hard, the lack of reliable modeling data is “worrisome,” Reed said.

Drylands take up drastically different amounts of carbon depending on precipitation, making them “incredibly important” to carbon budgets, said remote sensing scientist Dominic Fawcett from the Swiss Federal Research Institute WSL.

The ARID team hopes to study how climate change affects the distribution, function, structure, and biodiversity of drylands to understand the role this biome plays in Earth’s carbon cycle and how land managers can mitigate the impacts of climate change. The research would compare the western United States with drylands in Australia, Mexico, southern Africa, and South America.

Hundreds of people and communities contributed to the ARID proposal, including those tasked with protecting U.S. drylands, such as tribal nations and the U.S. Bureau of Land Management.

Community Impact

If only one of the two projects is funded, the chosen research community will receive “an incredible boost,” Reed said. That boost includes more than just funding: Expansive projects prompt scientists to cohere data from fields that are often siloed and create interdisciplinary communities that smooth the path to future discoveries. “That could be one of the key outcomes of the successful project,” Palmer said.

At the same time, “there’s a real urgent need to support elements of both of these [projects] because time is running out, frankly,” Ordway said.

Ordway said that if PANGEA wasn’t funded, the team would try to piece together smaller grants to subsidize the project. Reed said the ARID team will also try to continue their work if their project is not selected but has not made specific plans for how to do so. Working on the proposals has already galvanized work in both ecosystems, and Ordway and Reed both hope to see that momentum continue.

Early-career scientists could be the most affected by NASA’s upcoming decision because the experiences they have while working on field campaigns can be formative for their careers. Climate scientist Jennifer Watts, now at Woodwell Climate Research Center, remembered attending the first meeting of the ABoVE campaign when she was still a graduate student. “It was a small enough group that everyone talked to me, and they started to mentor me,” she said.

—Saima May Sidik (@saimamaysidik), Science Writer

Citation: Sidik, S. M. (2024), Next NASA field campaign could fund projects in drylands or tropics, Eos, 105, https://doi.org/10.1029/2024EO240497. Published on 1 November 2024.

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.