EOS

One Water, Many Solutions

To ensure the availability and sustainability of water resources and sanitation for all (United Nations Sustainable Development Goal 6), water managers and the communities they serve are investing in approaches that are both broad and deep.

The delegations that help drive the One Water approach to water management are wide-ranging and often serendipitous, as Grace van Deelen explains in “Delegations Drive One Water Dialogues.”  “One Water,” van Deelen writes, “treats drinking water, wastewater, and stormwater as a single, interconnected entity…bringing together water utilities, community members, business and industry leaders, researchers, politicians, engineers, and advocacy groups.

A comprehensive framework like One Water may also help address a long-standing injustice: why communities of color are more likely to have higher levels of contaminants in their drinking water.

In addition to applying integrated water management approaches involving at-risk communities, some scientists suggest that unconventional water resources should be explored for their potential to mitigate water insecurity. That’s the thrust of this month’s opinion, “Deep Groundwater Might Be a Sustainable Solution to the Water Crisis.” Contamination and overuse of shallow groundwater supplies are creating a need for in-depth analysis on the health, safety, and financial concerns associated with accessing deep aquifers, argue scientist-authors Claudia Bertoni, Fridtjov Ruden, Elizabeth Quiroga Jordan, and Helene Ruden.

Meeting water challenges requires the twin scientific skills of intersectional collaboration and data-driven research. This month’s stories show how Earth scientists are already pursuing such approaches and how they are looking to further develop the knowledge and networks to create more.

—Caryl-Sue Micalizio, Editor in Chief

Citation: Micalizio, C.-S. (2025), One Water, many solutions, Eos, 106, https://doi.org/10.1029/2025EO250154. Published on 24 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

One Water, Many Solutions

On a summer morning, a storm dropped buckets of rain on the desert outside Tucson, Ariz. Water ran over the dry soil. Most of the water subsequently evaporated, but some parched plants drank their fill. What was left over sank into the ground, percolating into the aquifer below.

A few kilometers down the road, Tucson Water pumped groundwater from the same aquifer to a nearby reservoir, then through its treatment system. A Tucson ratepayer turned on her tap and used a few liters of water to give her dog a bath. The soiled water flowed into Tucson’s wastewater system and once again was treated. A portion of that recycled wastewater was released into the Santa Cruz River, where parkgoers enjoyed watching it flow through the city.

In Tucson, as in the rest of the world, every human interaction with water is connected to a broader water system.

But water practitioners haven’t always treated their work with the same interconnected approach. Instead, many cities and regions divide their water into three silos: drinking water, wastewater, and stormwater, each managed separately.

That approach is not meeting the needs of many communities. And a different approach, called One Water, is beginning to take its place.

One Water treats drinking water, wastewater, and stormwater as a single, interconnected entity and attempts to manage it holistically, bringing together water utilities, community members, business and industry leaders, researchers, politicians, engineers, and advocacy groups.

Recycled water flows into the Santa Cruz River in Arizona as part of the Santa Cruz River Heritage Project. Credit: Tucson Water

In a One Water approach, the Tucson ratepayer, water utility, and parkgoer are equal stakeholders, and water practitioners attempt to create a water system that works well for each of them.

“Partnerships and collaboration are at its core,” said Scott Berry, director of policy and government affairs at the US Water Alliance, a nonprofit membership organization dedicated to advancing a “One Water future for all.”

A holistic, inclusive approach is not without obstacles, though. Different stakeholders bring different priorities and practices and may have cultural, historical regulatory, and organizational barriers that keep them from collaborating effectively.

To navigate such challenges, water stakeholders from varied sectors across the United States come together at an annual conference (soon to be held every 18 months), the One Water Summit, hosted by the US Water Alliance. About 70% of attendees come as part of a delegation, a peer group, typically organized by region, whose members want to work together on U.S. water issues.

These delegations are the lifeblood of the summit and uniquely mirror the One Water approach: They’re meant to be highly collaborative, allowing stakeholders with very different priorities to come together and work toward a common cause. Though the framework is hindered by funding constraints and a lack of engagement from some sectors, delegations have provided a valuable opportunity for sharing knowledge and bringing One Water projects to fruition.

Siloed Systems

In the water sector, siloed systems are the norm. The inertia they engender can be hard to break when trying to build collaborative networks.

In some cases, siloed approaches contribute to unaligned regulations, which can limit a collaboration’s success, explained Caity Peterson, a research fellow at the Public Policy Institute of California’s Water Policy Center.

For example, someone working on a wastewater problem must navigate both environmental and health regulations. A One Water program might involve potable reuse, or recycling wastewater into drinking water by purifying it, filtering it, and diverting it to groundwater or reservoir supplies. Such a project needs to ensure that the recycled water complies with environmental regulations that govern water quality for irrigation and other nonpotable uses. But once that water is destined for a drinking water supply, it must also comply with health regulations. “A little bit of streamlining” of those regulations can bolster collaboration, Peterson said.

Siloed jurisdictions can present another challenge for water practitioners. Though the flow of water respects no political or system boundary, water managers do work within such jurisdictions, said Sarin Pokhrel, a water resource engineer for the Environment and Protected Areas Ministry of Alberta, Canada. (Some local governments within Alberta, such as Edmonton, where Pokhrel is based, use a One Water approach.)

British Columbia, where Pokhrel previously worked, is home to an array of jurisdictions: Municipalities govern water via local bylaws, Indigenous communities manage their own water, and districts follow broader regional plans. Unifying plans under a single framework that all levels of water management can follow is very challenging, he said.

The US Water Alliance added the delegation structure to its annual conference in 2016 as a way for water practitioners to overcome these barriers and move toward One Water ideals. Berry, who leads delegation work at the US Water Alliance, said he thinks of the delegation system as an opportunity for stakeholders to “road test” collaborations.

“It’s a way to test the waters of collaboration away from the normal sphere of influence.”

“It’s this idea of getting a bunch of folks together who may not work together often, or who may even be at odds with one another,” he said. “It’s a way to test the waters of collaboration away from the normal sphere of influence.”

Organizers of the One Water Summit encourage delegations, which can be assembled by anyone with the interest, ability, and time to recruit fellow delegates, to attend. Delegation members can register at a discounted rate, and the summit provides opt-in programming specifically for delegates. Around one thousand people and 20–40 delegations attend each year. Membership in any one delegation has ranged from fewer than 10 to almost 50 people, Berry said.

The first half day of each summit is dedicated to “peer exchanges,” where delegations present their work to each other. These presentations range from showcasing a particular success to workshopping a problem that the delegation is facing, Berry said.

At the 2023 Tucson summit, for example, the Tap into Resilience delegation hosted a peer exchange to brainstorm how to scale up distributed water infrastructure, a type of ultralocal water system meant to be more affordable than conventional water systems. The Climate Action delegation shared strategies for utilities to use capital investments to make progress on their climate plans. And the New Jersey delegates hosted a discussion about how delegations can build relationships with state governments to advance One Water.

At an end-of-summit plenary, delegations are invited to announce “commitments to action” for the coming year.

“The entire plenary, you’re surrounded by all this amazing work that’s going to be happening in all these different places,” Berry said. “You get a sense that you’re not alone and that there are opportunities for collaboration.”

Commitments to action range from informal directives to full proposals. Delegations at the 2023 summit committed to developing new One Water plans for their cities, improving community engagement around water issues, sharing what they’d learned with local leaders and policymakers, and constructing new green stormwater and water treatment facilities. Delegations that return to the subsequent summit are encouraged to share how they’ve progressed on their commitments.

One Water, Many Networks

Water practitioners report a strengthening of the depth and breadth of their collaborations as a result of participating in a delegation.

“I felt like I really got to know people in a different way, not just as colleagues but as friends,” said Rebekah Jones, communications director for the Iowa Soybean Association’s Iowa Agriculture Water Alliance, who attended the 2023 One Water Summit as part of the delegation from Iowa. Jones deepened her relationships with colleagues at the city of Cedar Rapids and Des Moines Water Works and especially enjoyed meeting members of a delegation from Hawaii, who shared how critical water is to Hawaiian culture and livelihoods.

Jennifer Walker of the Texas delegation, director of the Texas Coast and Water Program at the National Wildlife Federation, said she feels the same after attending multiple summits. When a delegation convenes away from their home community, “everybody has a little bit more time to focus on the content, spend some time together, and build relationships,” she said.

“We can come together in ways that would be almost impossible at home.”

Because Texas is such a large state, the delegation venue is crucial for getting Texas stakeholders, including nonprofits, utilities, engineers, consultants, elected officials, and community members in the same room.

The delegations are building relationships among people who don’t work together day-to-day, said Michelle Stockness, executive director of the Freshwater Society, a nonprofit based in Saint Paul, Minn. Stockness attended the 2023 summit as a member of the Minnesota delegation. “We’re building those relationships so that we can talk about hard things a little more easily.”

“We can come together in ways that would be almost impossible at home,” said Candice Rupprecht, a water conservation program manager for the city of Tucson and a member of the Tucson delegation, in a 2019 presentation.

Strengthened relationships have sparked meaningful progress on One Water projects across the country.

At the Tucson, Ariz., One Water Summit in 2023, the Minnesota delegation shared concerns about water quality and distribution. Credit: Michelle Stockness

At the 2023 conference, the Iowa delegation held an educational session for other summit attendees about urban and rural collaboration via an exercise about a fictional town called Farmersville and its picturesque Crystal River. Attendees attempted to fix a water quality problem in Farmersville—a suddenly odorous and murky Crystal River—while playing a role that was different from their real-life job. For example, a water researcher could act as mayor, and a utility staff member could role-play a farmer.

In the scenario, the urban community blamed rural farmers for soil erosion and nutrient pollution, whereas farmers accused the city of industrial pollution and ineffective waste management. Workshop attendees had to navigate these concerns as they developed a plan to improve water quality.

“It got people thinking out of the box about what it’s like to be in someone else’s shoes,” Jones said.

In New Jersey, water practitioners had already formed a coalition of community members, nonprofit organizations, government entities, and utilities when the delegation from the state began attending the summit in 2016. Participating as a delegation supplemented the group’s holistic effort, said Paula Figueroa, director of the Jersey Water Works Collaborative and a former New Jersey delegate. For the New Jersey delegation, the summit is an important source of energy to balance the sometimes draining, difficult work of advancing a One Water approach, she said.

After the 2022 summit, Figueroa noticed that two leaders, one a New Jersey utility staff member and the other an employee of the Jersey Water Works Collaborative, began to collaborate, inviting each other to more events and sharing the other’s work. The new relationship increased the visibility of a shared, primary project: replacing lead service lines across the state.

The summit offers delegations opportunities for interstate cooperation as well. Following conversations between the Pittsburgh and Milwaukee delegations at the 2022 and 2023 summits, delegates from Pennsylvania and Wisconsin held a dedicated learning exchange in Milwaukee the following year.

Some water issues in Pittsburgh would have taken 2 or 3 years each to solve, but as a result of knowledge gained in the Wisconsin exchange, “we were able to complete five or six problems in 2 or 3 years,” said Jamil Bey, founder of the UrbanKind Institute and a longtime member of the Pittsburgh delegation. “That learning exchange model is really powerful.”

The event in Milwaukee helped inform a new approach to addressing stormwater reclamation in Pittsburgh, for instance, said Kelly Henderson, who was part of the Pittsburgh cohort that attended the learning exchange.

One of the locations the group visited was Green Tech Station, a former brownfield site that the Northwest Side Community Development Corporation, a nonprofit in Milwaukee, had transformed into a stormwater reclamation facility. Green Tech Station can capture more than 380,000 liters of stormwater each time it rains—water that is then used to irrigate trees on the site. The facility also includes a prairie ecosystem with native plants, a pavilion to host educational programming, and a collection of artwork.

Shown here is Green Tech Station in Milwaukee, a former brownfield site that was restored as a water reclamation system. In April 2024, members of the Pittsburgh delegation visited Green Tech Station as part of a learning exchange. Credit: Northwest Side Community Development Corporation

Henderson, executive director of Grounded Strategies, a nonprofit focused on community-driven vacant lot reclamation, found Green Tech Station so inspiring that she decided to create something similar in Pittsburgh. Grounded Strategies, along with partners from the Department of City Planning in Pittsburgh and the Pittsburgh Water and Sewer Authority and elsewhere, recently received a $55,000 grant to start the project. As they plan the site, they’ll be in close contact with the group that constructed Green Tech Station, Henderson said.

Delegations can also facilitate cooperation between stakeholders with different immediate interests.

In 2017, for instance, the Tucson delegation committed to a lofty goal: returning perennial water flow to the Santa Cruz River. At the time, the stretch of the river in downtown Tucson flowed only during rainstorms.

Rupprecht, the Tucson Water conservation manager and four-time Tucson delegation member, said delegation members were key to advocating for Arizona’s Drought Contingency Plan, a change in state law that increased recycled water recharge credits. Under the Drought Contingency Plan, Tucson Water can receive credits for 95% of the water released into the Santa Cruz River, then use those credits in the future to secure additional water supply.

Within a year, Tucson Water’s Santa Cruz River Heritage Project had released enough recycled water to the river that it flowed anew for the first time in almost 80 years. The new stretch of perennial river restored plants, revitalized a ciénaga (wetland) ecosystem, and provided new habitat for wildlife such as herons, native toads, coyotes, and dragonflies.

Inclusivity Obstacles

Though many delegations have made tangible progress toward One Water goals, barriers still exist to achieving full cross-sector engagement.

“With something like One Water…if you don’t do a good job of building those relationships and building those ties between sectors, then there’s a risk it could be just some pleasant marketing but not really delivering the outcomes that it’s supposed to deliver,” Peterson said.

One major barrier is money. Attending the summit comes at a financial cost that can be too high for underfunded organizations.“It’s all about money,” said Pokhrel, the Alberta engineer. “Do we have enough budget? Do we have enough resources to fulfill this?”

“Most of the most vulnerable people who are having water issues, they don’t have the resources to participate.”

“Most of the most vulnerable people who are having water issues, they don’t have the resources to participate,” Bey said. “There’s a minimum threshold for organizational capacity that you have to have to connect you to these types of conversations.”

The US Water Alliance tries to help delegates from underfunded organizations attend the summit with a tiered registration fee system. “If you’re a small nonprofit, you’re going to pay less than a private company or a large urban utility,” Berry said. “The people who are more resourced, who can afford to pay more, do pay more, and that helps us subsidize the cost for the folks who are less well resourced.”

A little funding can go a long way to help include historically marginalized voices. With help from a grant from the US Water Alliance, for instance, in 2023 the Minnesota delegation was able to invite representatives from the Indigenous-led nonprofit Honor the Earth, as well as community members from the Environmental Justice Coordinating Council (EJCC). Members of EJCC had previously attended the 2022 One Water Summit in Milwaukee, where they had committed to working on issues of environmental health in Minnesota, particularly the impact of per- and polyfluoroalkyl substances (PFAS) on drinking water.

“Providing funding for community and tribal members was really important to get the people we wanted to be there and have that diverse representation.”

“Providing funding for community and tribal members was really important to get the people we wanted to be there and have that diverse representation of multiple perspectives,” Stockness said.

Delegates from Honor the Earth and EJCC could not be reached for comment in time for publication.

Berry and some past delegates said they feel that the agriculture industry is underrepresented at the summits, too. Agriculture is a huge element of the water system, responsible for about 70% of freshwater use worldwide. The proportion of agriculture practitioners at the summit is “still not as big as it could be, or should be,” said Sean McMahon, a sustainable agriculture consultant who has been involved in coordinating the Iowa delegation for five summits.

City utilities make up the majority of membership in the US Water Alliance, and urban organizations dominate the summit—a dynamic that may make the rural agriculture community feel ostracized, Peterson said. If members of the agriculture community are not engaging in a collaboration, that might mean the benefit of participating is not clear to them.

As in the fictional Farmersville, agriculture communities and urban water suppliers may not always see eye to eye. Farmers may be frustrated with what they see as overly restrictive regulations in an already difficult economic environment, whereas urban utilities prioritize delivering clean drinking water to their ratepayers.

The agriculture sector often gets cast as a villain and may feel that it must defend itself against other water practitioners who aren’t familiar with the hardships of farm operations, Peterson said. Making clear to farmers the mutual benefits of a One Water approach could improve collaboration. For instance, many sustainable agriculture practices both benefit farm finances and improve downstream water quality.

McMahon recommended that delegation leaders reach out to agriculture associations to find champions of improving water quality and water use efficiency. “If you’re framing your proposal like, ‘Come help us talk about these complicated issues from your perspective,’ it’s like a wide-open door to have really powerful conversations,” said Jones.

“The water is the bridge.”

Clare Lindahl, chief executive officer of the Soil and Water Conservation Society, a member of the Soil and Water Conservation delegation, and a board member of the US Water Alliance, said her delegation has had success building relationships across the urban and rural divide by emphasizing the value of water to all stakeholders. “The water is the bridge,” she said.

When a highly diverse group of stakeholders makes it to the summit, collaboration can lead to what Figueroa called a “healthy push and pull”: Everyone sitting around the table may have different expectations, goals, and work practices. Delegations have found that defining common goals and outlining clear responsibilities are the best way around that.

For example, the New Jersey group has centered its conversations around four shared goals: having effective and financially sustainable water systems; empowering stakeholders and ensuring that they are well-informed; building successful, beneficial green infrastructure; and creating smart combined sewer overflow control systems.

“That’s our North Star, and that has helped us,” Figueroa said.

“It’s hard to break down silos if your objectives aren’t clear,” Peterson said. Being “really candid and clear about who’s involved, what the roles are, and what the responsibilities are for the beginning, middle, and end of the project” can help, she said.

Berry said he has high hopes for the future of delegations. He imagines an eventual Colorado River delegation that would include stakeholders from throughout the Colorado River Basin. Other dreams include a Great Lakes delegation and a Mississippi River delegation. “There’s so much ground to cover,” he said.

“It’s both a resources and money question, and it’s a relationship question,” Berry said.

—Grace van Deelen (@GVD__), Staff Writer

Citation: van Deelen, G. (2025), Delegations drive One Water dialogues, Eos, 106, https://doi.org/10.1029/2025EO250155. Published on 24 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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

The massive 2022 eruption of the Hunga Tonga-Hunga Ha‘apai volcano was one of the most powerful explosions ever recorded. It blasted ash and gas high into the sky, reaching heights over 50 kilometers (above most clouds and weather), and sent waves rippling through Earth’s atmosphere. These waves traveled all the way to the upper atmosphere—the netherworld where satellites orbit—causing unexpected disruptions in this region.

Using data from satellites and computer models, Li et al. [2025] investigate why these waves spread so far. They focus on two possible causes: Lamb waves (pressure waves that “hug” Earth’s surface) and secondary gravity waves (new waves created when initial eruption waves break apart higher up). The authors find that secondary gravity waves, with their faster speeds and larger magnitudes, matched the satellite observations best. This means they were the key driver of the upper atmosphere’s dramatic changes.

These findings matter because they reveal how geological events on Earth’s surface, like volcanoes, can “talk” to the edge of space. Understanding this link helps improve satellite safety and weather predictions in space, which is critical as humans rely more on satellites for communication, navigation, and climate monitoring.

The numerical simulations reveal that secondary gravity waves could be responsible for the large scale thermospheric disturbances captured by GRACE-FO satellite associated with the extraordinary eruption of the Tonga volcano on 15 January 2022. Credit: Li et al. [2025], Supporting Information Movie S1

Citation: Li, R., Lei, J., Zhang, S.-R., Liu, F., Chen, X., Luan, X., & Meng, X. (2025). Were gravity waves or lamb waves responsible for the large-scale thermospheric response to the Tonga eruption? AGU Advances, 6, e2024AV001470. https://doi.org/10.1029/2024AV001470

— Binzheng Zhang, Editor, AGU Advances

Text © 2024. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Earth’s oceans are full of plastic. Though the state-sized garbage patches formed by ocean currents are the most visible, just an estimated 1% of ocean plastic lurks on the surface. The other 99% hides elsewhere in the ocean and may be found in the deep sea, mixed in with seafloor sediment. These particles are often in the form of microplastics: fragments of plastic goods degraded to less than 1 millimeter in length.

Scientists know these deep-sea plastics don’t get there by simply sinking from the surface since their distribution doesn’t match the locations of surface garbage patches. Results of laboratory experiments and seafloor sampling campaigns led scientists to suspect these plastic particles instead reach the deep ocean via turbidity currents, gravity-driven cascades of sediment-rich water that flows from rivers over the continental shelf and down to the seafloor. But no one had observed the process until now.

A new study published in Environmental Science and Technology presents the first direct evidence of an underwater microplastics “avalanche,” a turbidity current that transported plastic pollution to the bottom of a deep ocean canyon. The findings raise concerns about how microplastics may be affecting marine organisms because the same turbidity currents foster biodiversity hot spots in the same locations.

“The fact that we captured this in action proves the theory, but it also highlights the threats that microplastics pose.”

“Turbidity currents are an important process that transports sediments and nutrients to the deep sea. The question was: Do they also transport plastics?” said Florian Pohl, a sedimentologist at the University of Bayreuth in Germany who was not involved in the research. Pohl was the lead author on a 2020 study that predicted the existence of these microplastics “avalanches” using laboratory experiments.

“The fact that we captured this in action proves the theory, but it also highlights the threats that microplastics pose,” said Ian Kane, a coauthor of the new study and a sedimentologist at the University of Manchester. “This study is further evidence of the impact that we’re having on the oceans.”

Measuring Microplastics

To observe turbidity currents in action, the research team headed to Whittard Canyon, an undersea canyon in the Celtic Sea nearly 4 kilometers (2.5 miles) deep. They installed sensors in the canyon that could measure turbidity current velocity and detect sediment concentration.

The team also installed a sediment trap just above the seafloor to collect material transported by the turbidity current and drilled cores of seafloor and subseafloor sediment at seven sites at varying depths in the canyon.

Between June 2019 and August 2020, the sensors detected six turbidity currents, the first of which filled the sediment trap. An analysis of flow velocity and sediment grain size showed that the turbidity flow even carried large plastic litter, including segments of plastic fishing line. All sediment trap samples and seafloor sediment cores contained microplastic particles.

The sediment trap, which collected sediment from the first observed turbidity flow, yielded 82 microplastic items per 50 grams of dried sediment. Credit: Peng Chen

Samples of sediment from the cores revealed that the relative proportion of microplastic fragments (tiny plastic “chunks”) to microplastic fibers (from synthetic textiles) increased deeper into the canyon, indicating that fragments and fibers travel differently in turbidity currents. Pohl said he’d like to take a closer look at the fragment and fiber properties (such as the type of plastic they’re made of) to determine why.

Kane was struck by the high concentrations of microplastics found in the sediment, especially because Whittard Canyon is so far from shore—300 kilometers (186 miles). “It’s quite alarming that this material is making its way so far out into ocean basins,” he said.

The microplastics “avalanches” observed in Whittard Canyon likely also happen elsewhere in Earth’s oceans. More than 5,000 similar canyons worldwide could be important conveyors of pollution to the deep sea, the authors wrote. Some of these canyons are fed directly by rivers on land. Seasonal flash floods in Sicily, for instance, have carried large amounts of plastic litter to submarine canyons.

If Whittard Canyon is receiving a lot of plastic, it’s likely that other canyons, especially those more closely linked to rivers on land, are receiving even more, Kane said.

Plastic in the Ecosystem

The new study is a “great first step” in understanding how microplastics reach the deep ocean, Pohl said. “It’s a big piece of the puzzle to understand that these flows do indeed transport microplastics. But now there are follow-up questions, like how much [plastic] do they actually transport? And how does this relate to the overall budget of ocean floor plastics?”

The same turbidity currents that flush microplastics also bring oxygen and nutrients to the deep sea, forming biodiversity hot spots in the same locations where plastic pollution accumulates. That plastic pollution often contains toxic ingredients that are hazardous to marine organisms.

“Magnification through the trophic web is a real danger.”

Filter feeders ingest toxic plastic particles, which accumulate up the marine food chain. “Magnification through the [food] web is a real danger,” Kane said.

Much of the plastic in the ocean enters via waste management systems. Better filtration at wastewater treatment plants could be one important way to reduce the flow of microplastic fibers into the ocean, Kane said, adding that fishing and shipping are also major sources of microplastics to target for mitigation. But microplastic pollution is ubiquitous in the environment, and reducing its presence in the ocean is “a big challenge,” Pohl said.

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

Citation: van Deelen, G. (2025), Avalanches of microplastics carry pollution into the deep sea, Eos, 106, https://doi.org/10.1029/2025EO250153. Published on 23 April 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Geophysical Research Letters Sampling red snow on the Tasman Glacier in the Southern Alps following the 2019-2020 Australian bushfire/dust storm (Photo: J. Hunt 11/02/2020). Credit: Winton et al. [2024], Figure 1d

New research reveals the source of the red dust that blanketed the New Zealand Southern Alps in the summer of 2019-2020 following the severe Australian bushfires. While much attention was paid to ash from the extreme 2019-2020 Australian fires, a surprising discovery is that transport of dust generated from dust storms was also a major contributor to the composition of the atmosphere at the time.

Winton et al. [2024] analyze snow samples from the Fox, Franz Josef, and Tasman glaciers and geochemically fingerprint its origin as southeast Australia where desert dust storms transported massive amounts of red dust across the Tasman Sea. These dust storms were fueled by the same high winds that also drove the bushfires and transported an estimated 4,500 tons of red mineral dust to the snow and ice in the Southern Alps. While the dust storm event lasted only a short time, it could have long-term effects on glacier melting.

Citation: Winton, V. H. L., Charlier, B. L. A., Jolly, B. H., Purdie, H., Anderson, B., Hunt, J. E., et al. (2024). New Zealand Southern Alps blanketed by red Australian dust during 2019/2020 severe bushfire and dust event. Geophysical Research Letters, 51, e2024GL112782. https://doi.org/10.1029/2024GL112782  

—Bin Zhao, Associate Editor, Geophysical Research Letters

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.

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

After 5 years of organizing TierraFest, an annual event that celebrates the Earth sciences in Mexico, one of the things Raiza Pilatowsky Gruner has learned is that when it comes to communicating knowledge about our environment, “we scientists are not the people with the greatest authority. We all live on this planet.”

“There are many other ways to generate knowledge, to validate it and live it.”

She explained this during the event’s press conference, where she also announced the theme for this year’s festival: “Together Against the Storm.” The organizers of TierraFest didn’t want to convey the idea that scientists are the only source of solutions to problems such as climate change, said Pilatowsky Gruner. That’s been a consistent value held at Planeteando, the nonprofit behind TierraFest.

Though the scientific method is valid and important, “there are many other ways to generate knowledge, to validate it and live it,” Pilatowsky Gruner added. She believes that this philosophy has made TierraFest a safe place for diversity in an uncertain political landscape.

This week, Mexico City will host a science fair, live performances, and films for people of all ages to reflect on the relationship we all have with the planet.

Horizontal Learning

One example of the diversity at this year’s festival is its opening event, said Carla Chávez, who started as a social service intern at Planeteando and is now a regular collaborator. On 22 April (Earth Day), TierraFest kicks off with a hike in Los Dinamos National Park, a forest home to the Río Magdalena, the last free-flowing river in the Mexican capital.

“We believe in horizontal learning. We learn from them, and they learn from us.”

Chávez, a biologist at the National Autonomous University of Mexico (UNAM), explained that Planeteando doesn’t want to be intruders in La Magdalena Atlitic, a historic community where the hike will take place. “We believe in horizontal learning,” she said. “We learn from them, and they learn from us.”

During the hike, Marisol Tovar Valentínez and her team of communal monitors—community members who volunteer to take care of their forest—will guide participants through their forest, joined by TierraFest organizers and National Geographic Explorer Daniela Cafaggi.

As part of horizontal learning, communal monitors in training will join the hike to learn from the TierraFest team and practice their skills in guiding groups. They will also share their knowledge of the forest with attendees.

Unlike Pilatowsky Gruner, Tovar Valentínez said she thinks that scientists may, indeed, have an authoritative voice over knowledge about the planet. “But not over wisdom,” she said, describing wisdom as knowledges created and protected in communities like hers. Wisdom is a continuous and living process, she said, although it is in danger of being lost as community elders die.

Tovar Valentínez said she values working with scientists, including Cafaggi, a biologist from UNAM who worked with the Atlihtic community to study bats in their forest.

Uniting Different Perspectives

On 24 April, TierraFest continues with the annual Beers to Cool the Planet event, during which scientists and activists share opinions and perspectives over drinks.

Pilatowsky Gruner explained at the press conference that organizers want to use TierraFest 2025 to highlight the importance of uniting people from different backgrounds, “Together Against the Storm.” Such unity can help individuals and communities face both climate change and global trends like extractivism, both “storms” touching the entire world.

After drinks, the celebration of diverse approaches to Earth’s challenges continues. Chávez will crawl into the skin of Carmilla Desmodus, a drag queen inspired by the iconic lesbian vampire from the book Carmilla by Irish author Joseph Sheridan Le Fanu and Desmodus, the genus of blood-sucking “vampire bats.”

“Drag for the Earth” emerged as an annual event at TierraFest 3 years ago, when drag queen Bia Hollis was invited to perform. Pedro Adad Tristán Flores, the UNAM biologist behind Bia Hollis, was also a social service intern with Planeteando before becoming a regular collaborator. Since then, her collective of drag queens takes inspiration from TierraFest’s theme each year to design their wardrobe and makeup, which they explain during the show.

This year, TierraFest’s LGBTQ+ focused activities will expand to include a playback performance by the collective Xuir, in which audience members will tell personal stories while the performers interpret them live. Organizers will prompt stories about the intersection between scientific work and LGBTQ+ identities.

Showing Attendees the World

On 26 April, TierraFilme will present another edition of films about planet Earth. For the first time, this event will be held at the Papalote Children’s Museum, a space dedicated to science communication for kids, and will kick off with episodes from the National Geographic docuseries A Real Bug’s Life. Attendees will see short films from Mexico and throughout Latin America on topics such as the effect of waste, the loss of Indigenous languages, and the impacts of urban expansion.

Events at TierraFest will wrap up on 27 April, when El Rule Cultural Center, the festival’s longtime home, will once again host the TierraFest Science Fair. Activists and scientists will showcase their work for adults and children in more than 20 workshops on water, air, Earth, and life. From life in Paleozoic seas to contemporary issues like the impacts that an undersea pipeline might have on whales, these Earth scientists are focused on better understanding the planet and sharing that knowledge with all.

—Roberto González (@ggonzalitos), Science Writer

Citation: González, R. (2025), Knowledge flows both ways at TierraFest 2025, Eos, 106, https://doi.org/10.1029/2025EO250158. Published on 22 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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

On 21 April, the Environmental Protection Agency notified hundreds of employees working on diversity, equity, and inclusion and environmental justice issues that they would be fired or reassigned to other positions.

Citing two executive orders that aim to end DEI programs and to implement the Department of Government Efficiency, a notice sent to employees by Travis Voyles, assistant deputy administrator of the agency, said the reduction in force “will directly benefit the American people and better advance the Agency’s core mission of protecting human health and the environment.”

In February, the EPA placed the entire, nearly 200-person Office of Environmental Justice and External Civil Rights staff on leave. The agency then reinstated dozens of the positions in March. As reported by The Washington Post, the new “reduction in force” will cut 105 staffers, effective 31 July, and reassign another 175, effective 29 June.

Earlier in the day on 21 April, EPA administrator Lee Zeldin held a press briefing at EPA headquarters in Washington, D.C. When asked how he would ensure the agency’s work reflected the Trump administration’s priorities, he said he was soliciting input from staff on how they think the agency could operate better.

 
Related

•  EPA to fire or reassign nearly 300 staffers working on environmental justice, DEI
•  EPA begins layoffs of environmental justice staff
•  E.P.A. Set to Cancel Grants Aimed at Protecting Children From Toxic Chemicals
• Get Involved: AGU Science Policy Action Center

“Number one is I think it’s incredibly important for us to fulfill all statutory obligations,” he said. “Two, I do not want to lose one good employee, and we’re going to be very thoughtful and deliberate in how we go forward.”

As reported by The New York Times, the EPA is also planning to cancel tens of millions of research grants researching topics such as the health effects of pesticide exposure, wildfire smoke, and Per- and poly-fluoroalkyl substances (also known as PFAS, or “forever chemicals”).

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

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

From a flurry of executive orders to a new Department of Government Efficiency, the administration of U.S. President Donald Trump has introduced a broad agenda promising to usher in “the Golden Age of America.”

The agenda includes major and minor changes to science policy. Our new tracker lets you sift through chronology and categories critical to the Earth and space sciences:

• Climate & Energy
• Environment & Health
• Federal Workforce
• Universities and Academia

View the tracker in full screen here.

Science and scientists are affected by a much wider range of policies, of course—immigration, trade, social justice. Scroll to the end of this post for a broad list of comprehensive and targeted trackers.

We encourage you to visit these trackers to better understand the scope and sequence of the administration’s actions and statements.

Comprehensive

• Akin: Trump Executive Order Tracker
• AP: Tracking Trump’s Presidential Promises
• CNN: Tracking Trump’s Executive Actions
• Dentons: Trump Administration Tracker
• Forbes: Trump Tracker
• The Guardian: Tracking Trump – updates on the presidency’s first 100 days
• Mayer Brown: Trump 2.0 Executive Order Tracker
• New York Times: All of the Trump Administration’s Major Moves
• Sheppard Mullin: Trump Administration Executive Actions Tracker
• Wall Street Journal: The Trump Tracker

Science, Climate, and Academia

• The Chronicle of Higher Education: Tracking Trump’s Higher-Ed Agenda
• Climate Action Campaign: Trump’s Climate and Clean Energy Rollback Tracker
• Environmental Data & Governance Initiative: Federal Environmental Web Tracker
• Grant Tracker: NIH Grant Terminations in 2025
• Guarini Center: Plastics Litigation Tracker
• Harvard Law School Environmental & Energy Law Program: Federal Environmental Justice Tracker
• Inside Higher Education: International Student Visas Revoked
• Journals No Longer Being Indexed by ERIC
• National Council of Nonprofits: Executive Orders Affecting Charitable Nonprofits
• Sabin Center for Climate Change Law: Inflation Reduction Act Tracker
• Sabin Center for Climate Change Law: Silencing Science Tracker
• Science: Trump Tracker

Government Data, Funding, and Layoffs

• Citizens for Responsibility and Ethics in Washington: Trump Firings Tracker
• CNN: Tracking Trump’s Overhaul of the Federal Workforce
• The Data Rescue Project
• The Impact Project: The Impact Map
• OpenOMB: Tracking apportionments
• Tracking Missing and Modified Government Documents & Information – PILOT

Litigation

• Civil Rights Litigation Clearinghouse: Clearinghouse is tracking Trump Administration litigation and challenges
• Just Security: Litigation Tracker: Legal Challenges to Trump Administration Actions
• Lawfare: Trump Administration Litigation Tracker
• Littler Mendelson: Rescinded Order Tracker
• National Conference of State Legislatures: Congressional Review Act – Overview and Tracking
• New York Times: Tracking the Lawsuits Against Trump’s Agenda
• SCOTUSblog: Emergency Docket 2024-25
• U.S. News & World Report: These Are the Lawsuits Against Trump’s Executive Orders
• Washington Post: Which Trump initiatives have been halted, or allowed, for now

Immigration

• American Immigration Lawyers Association: Tracking Notable Executive Branch Action during the Second Trump Administration
• Immigration Policy Tracking Project

Trade

• Atlantic Council: Trump Tariff Tracker
• Reed Smith Trade Compliance Resource Hub: Trump 2.0 Tariff Tracker
• Tax Foundation: Trump Tariffs

Political Appointees

• AP: Trump Cabinet confirmation status: Which nominees have been confirmed?
• Washington Post and Partnership for Public Service: Political Appointee Tracker

Project 2025

• Project 2025 Tracker

Tracking the Trackers

• Harvard Law School Environmental & Energy Law Program: Trackers from Other Institutions
• UC San Diego Library: U.S. Government Information: Trump Trackers

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

Source: AGU Advances

Enhanced rock weathering (ERW) is a proposed method of carbon dioxide sequestration that involves spreading crushed silicate minerals on soils to drive chemical reactions that form carbonate minerals: Essentially, the idea is to boost the natural process of rock weathering, in which carbon is transferred from the atmosphere into rocks. But few large-scale field studies of ERW exist, making it difficult to determine the technique’s practical feasibility and what factors might limit or enhance its success.

To address this knowledge gap, Anthony et al. conducted a 3-year, ecosystem-scale study to assess ERW in a California grassland environment, as well as the benefits of enhancing applications of crushed rock with organic additives.

The researchers spread finely crushed metabasaltic rocks across test plots in Browns Valley, Calif., in each of the 3 years. Along with the crushed rock, some of the applications included compost or a combination of compost and biochar (in this case, burned pine and fir left over from local logging). Other plots were treated with only compost, and a group of control plots received no treatment. Throughout the year, the team monitored each plot for levels of soil organic and inorganic carbon, pore water dissolved carbon, aboveground biomass, and greenhouse gas emissions.

The results showed that the rock-only plots sequestered only small amounts of carbon, though they helped reduce organic carbon losses compared with the control plots. Combining crushed rocks, compost, and biochar yielded the best results; in addition to sequestering carbon, the mixture both reduced nitrous oxide emissions and increased methane conversion, resulting in increased greenhouse gas mitigation overall.

The researchers estimate that if the combination of all three materials were expanded to cover 8% of California’s total rangelands, it could sequester up to 51.7 million metric tons of carbon dioxide equivalent per year. However, that amount is about a quarter of the theoretical maximum for carbon sequestration from ERW in the area, according to the authors, indicating that achieving theoretical yields may be difficult in practice.

The authors note that their study took place during a drought, which may have decreased sequestration. They also point out that other “life cycle” emissions associated with ERW, such as those generated by producing, transporting, and applying treatments, must be factored into full assessments of the method’s impacts. (AGU Advances, https://doi.org/10.1029/2024AV001480, 2025)

—Nathaniel Scharping (@nathanielscharp), Science Writer

Citation: Scharping, N. (2025), Compost and biochar could boost carbon sequestration by crushed rock, Eos, 106, https://doi.org/10.1029/2025EO250083. Published on 22 April 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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

A clear and consistent framework for the detection and classification of all cyclones — ranging from hurricanes and winter storms to monsoon-related events — is beneficial for the scientific research community because it can aid process-level understanding, enhance the efficiency of operational forecasting, and increase effective communication of risks. Ultimately, such a framework can safeguard lives and infrastructure.

Han and Ulrich [2025] present a novel detection and classification framework called the System for Classification of Low‐Pressure Systems (SyCLoPS). The authors use the data-driven framework to classify 16 different types of low-pressure systems across the world.  SyCLoPS — a suitable designation based on the all-seeing Greek mythical Cyclops — is a fitting designation for a system designed to detect and track all kinds of storms, anywhere in the world.

SyCLoPS was used to identify more than 379 thousand distinct storm tracks through high-resolution global data sourced from the European Center for Medium Range Weather Forecasting’s global data product between 1979 to 2022. The author’s approach — the first to classify all low-pressure systems using a single global dataset — can be applied to any dataset that includes a basic set of atmospheric parameters, enabling consistent characterization and categorization of low-pressure systems. The implications are significant. Why? Because such a framework can use historical data to understand past trends and can be used to perform analysis of future projections, to improve understanding of likely changes.

Maintaining a consistent framework for the detection and classification of all cyclones is essential for improving understanding of how a warming climate may influence their frequency, landfall patterns, and impact zones. These changes could affect both densely populated urban areas and non-urban regions, including key agricultural zones that may become more vulnerable to storm activity. This study represents an important step toward building a unified framework for consistently identifying and linking past and future projections of storm systems.

Citation: Han, Y., & Ullrich, P. A. (2025). The system for classification of low-pressure systems (SyCLoPS): An all-in-one objective framework for large-scale data sets. Journal of Geophysical Research: Atmospheres, 130, e2024JD041287. https://doi.org/10.1029/2024JD041287

—Matei Georgescu, Associate Editor, JGR: Atmospheres

Text © 2024. The authors. CC BY-NC-ND 3.0
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body {background-color: #D2D1D5;} Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today.

The National Science Foundation has cancelled hundreds of grants to researchers working on projects related to diversity, equity, and inclusion, as well as misinformation and disinformation.

In a statement posted on its website, NSF director Sethuraman Panchanathan wrote that the agency’s efforts to promote the progress of science should not preference some people, such as women or those from underrepresented groups, over others.

 
Related

•  NSF starts to kill grants that violate Trump’s war on diversity efforts
•  National Science Foundation cancels research grants related to misinformation and disinformation
•   Get Involved: AGU Science Policy Action Center
 

“Research projects with more narrow impact limited to subgroups of people based on protected class or characteristics do not effectuate NSF priorities,” he wrote. “Awards that are not aligned with NSF’s priorities have been terminated, including but not limited to those on diversity, equity, and inclusion (DEI) and misinformation/disinformation.”

A post on the Department of Government Efficiency’s X account said NSF had cancelled 402 grants, worth $233 million.  

Great work by @NSF canceling 402 wasteful DEI grants ($233M in savings), including $1M for “Antiracist Teacher Leadership for Statewide Transformation”.

See the NSF update below. Grant awards will be based on merit, competition, equal opportunity, and excellence. https://t.co/Zptp92uBkm

— Department of Government Efficiency (@DOGE) April 19, 2025

Funding was cancelled for a range of projects including one studying efforts to limit the spread of inaccurate information online and another using community-based science to research the effects of extreme heat in racially and ethnically diverse communities.

I got an email yesterday afternoon that my NSF SPRF Postdoctoral Fellowship was terminated. My grant focused on testing interventions to address online misinformation and I was 8 months into a two year appointment.

— Maddy Jalbert (@maddyjalbert.bsky.social) 2025-04-19T16:43:38.391Z

The announcement follows a 21 January executive order from President Trump that ordered all executive departments and agencies to terminate all “dangerous, demeaning, and immoral race- and sex-based preferences under the guise of so-called “diversity, equity, and inclusion” (DEI) or “diversity, equity, inclusion, and accessibility” (DEIA).”

I’m so angry & heart broken. My NSF CAREER grant was stolen today; dream project supporting science teachers/students as climate justice action researchers, tackling urban heat. Truly transformative, the culmination of my life’s work, we won’t stop, not in this climate crisis. Gonna fight like hell!

— Tammie Visintainer (@proftv.bsky.social) 2025-04-19T05:37:10.060Z

The NSF statement also cited President Trump’s 20 January executive order (one of 26 signed on his first day in office): Restoring Freedom of Speech and Ending Federal Censorship. “Under the guise of combatting ‘misinformation,’ ‘disinformation,’ and ‘malinformation,’ the Federal Government infringed on the constitutionally protected speech rights of American citizens,” the order read.

Noam Ross, a computational researcher and the director of rOpenSci, and Scott Delaney, an epidemiologist at Harvard, created an Airtable form in which researchers can report their grant cancellations.

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. Text © 2025. AGU. CC BY-NC-ND 3.0
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In 2004, the Indianapolis 500 turned into the Indianapolis 450. Organizers shortened the famous automobile race by 20 laps (50 miles) after a tornado touched down near the Indianapolis Motor Speedway, where more than 200,000 spectators were in attendance. Large outdoor gatherings such as this expose event-goers to the elements, and in some parts of the United States, severe weather can make that pairing deadly.

That’s especially true of the New Orleans Jazz & Heritage Festival in Louisiana, which poses the highest lightning risk of more than 16,000 large outdoor gatherings analyzed by researchers in a recent study. Coors Field in Denver and an amusement park in Arlington, Texas, topped the study’s lists for tornado exposure. The findings increase awareness of weather-related hazards among event attendees and venue managers alike, the researchers suggested.

Only a handful of studies have attempted to quantify weather-related risks at large outdoor gatherings, and even fewer have attempted to do so for a variety of events that occur across a large geographic area.

Stephen Strader, a hazards geographer and atmospheric scientist at Villanova University in Pennsylvania, and Jack Deppman, a doctoral student in geospatial analytics at North Carolina State University in Raleigh, recently did just that. Strader and Deppman focused on two forms of extreme weather—tornadoes and lightning—and determined risk indices for large outdoor gatherings across the United States.

The researchers started by mining tornado and lightning data. They analyzed a NOAA dataset of tornadoes that touched down between 1954 and 2020 and a dataset of cloud-to-ground lightning strokes pinpointed by the Earth Networks’ Total Lightning Network from 2012 to 2020. For each type of hazard, the researchers calculated the average number of occurrences each month within grid cells measuring 80 × 80 kilometers.

Follow the Crowds

Strader and Deppman next assembled a list of large outdoor gathering spaces. The public venues tabulated in the Department of Homeland Security’s Homeland Infrastructure Foundation-Level Data dataset served as a basis, and the researchers supplemented that listing with other locations such as football stadiums, concert venues, and horse racetracks.

For each location, Strader and Deppman determined the dates of events that occurred primarily outdoors and each event’s maximum seating capacity. To do that, they mined sources ranging from reports to venue websites to news articles. Amassing all that information took about a year.

After limiting their final list of events to those that could accommodate at least 10,000 people, the researchers identified 16,232 unique events held at 477 venues. “It’s a lot of data,” said Deppman.

Next, the team determined risk indices for each event. Strader and Deppman’s calculations took into account an event’s maximum seating capacity, its frequency in terms of number of days per month, its seasonality, and the tornado and lightning climatology of its location. “We needed to capture all of those elements,” Strader said.

Strader and Deppman calculated one lightning risk index and two tornado risk indices for each event. It was important to consider the risk of experiencing any tornado, independent of magnitude, and also the risk of experiencing a more damaging tornado, Strader said. That’s because though more than four out of five tornadoes are classified as EF0 or EF1 on the Enhanced Fujita damage intensity scale, the vast majority of tornado-related fatalities occur during tornadoes rated EF2 or higher. “They’re responsible for 99% of deaths,” Strader said.

Music, Baseball, Roller Coasters, and More

When the researchers ranked the events, they found that the New Orleans Jazz & Heritage Festival topped the list for potential lightning exposure. “That stuck out like a sore thumb from the lightning standpoint,” Strader said. This event, which draws roughly half a million attendees annually over a week and a half, occurs in April–May, which is when the risk of cloud-to-ground lightning peaks in southern Louisiana. All of the other events in the top 10 for lightning exposure were at amusement parks in Florida.

“Amusement parks dominate the scores because they’re open so many days per year.”

Coors Field in Denver in June topped the list for exposure to EF0–EF5 tornadoes. Other venues on the top 10 list included the New Orleans Jazz & Heritage Festival; several amusement parks in Texas, Florida, and Missouri; and the State Fair of Texas in Dallas.

When the team limited their analyses to more damaging tornadoes registering EF2–EF5, the Six Flags Over Texas amusement park in April was ranked first. Other amusement parks in Ohio, Florida, and Texas joined the top 10 list, as did Globe Life Field, a Major League Baseball stadium in Texas; the State Fair of Texas in Dallas; the Texas Grand Prix; and the Indianapolis Motor Speedway.

“Amusement parks dominate the scores because they’re open so many days per year,” Strader said. The team’s results were published in Weather, Climate, and Society, and the full ranking of events is available upon request from the authors.

It’s important for the operators of venues to look at these results, said John Jensenius, a meteorologist and lightning safety specialist and a member of the National Lightning Safety Council, who was not involved in the research. But event attendees also have responsibility for their own safety, he added. With weather apps widely available, people can make educated choices about whether to attend a particular event. “Avoidance is always the best answer if you think there’s going to be lightning at an event,” Jensenius said.

“Venues need to be, and generally are becoming, better prepared for these types of events.”

Some venue managers and event organizers are already taking weather-related risks seriously. Last year, a football game between Penn State and West Virginia universities was interrupted by lightning, and officials opted to evacuate Mountaineer Field at Milan Puskar Stadium, an outdoor space capable of holding roughly 60,000 fans. “Venues need to be, and generally are becoming, better prepared for these types of events,” said Roger Edwards, who retired last year as a meteorologist and lead forecaster at NOAA’s Storm Prediction Center in Norman, Okla. Edwards was not involved in the research.

Strader is now thinking of ways to expand the team’s database. There’s plenty of other forms of extreme weather that could wreak havoc on a large outdoor gathering, he said. “What about wind, hail, flash flooding?”

—Katherine Kornei (@KatherineKornei), Science Writer

Citation: Kornei, K. (2025), Large outdoor gatherings expose event-goers to severe weather, Eos, 106, https://doi.org/10.1029/2025EO250152. Published on 21 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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

Los castores construyen presas en los ríos. Las hormigas construyen montículos y excavan túneles. Los peces que buscan alimento desplazan partículas en los lechos de los ríos. El ganado doméstico compacta el suelo bajo sus pezuñas. Durante décadas, los investigadores han documentado las formas en que diversas especies modifican sus ambientes. Sin embargo, aún no está claro cuál es el impacto de todo este movimiento de tierra.

“La biología compite con las fuerzas geofísicas en la transformación de los paisajes”.

Una nueva investigación estima que los animales silvestres invierten anualmente 76,000 gigajulios de energía en la transformación de los paisajes terrestres, una cantidad equivalente a la de cientos de miles de inundaciones extremas. La contribución energética del ganado excede esta cifra en tres órdenes de magnitud.

“Existe la idea de que estos son procesos curiosos, únicos o inusuales”, señaló Gemma Harvey, coautora del estudio y geógrafa física en la Universidad Queen Mary de Londres, Reino Unido. Los investigadores frecuentemente piensan que el impacto geomorfológico—o moldeador del paisaje—de los animales es interesante, pero no particularmente significativo, explicó. Sin embargo, la nueva investigación demuestra que “la biología compite con las fuerzas geofísicas en la transformación de los paisajes”.

Harvey y sus colegas se sumergieron en la literatura científica en busca de estudios sobre las acciones geomórficas de los animales. Basados en investigaciones en inglés sobre ecosistemas terrestres y de agua dulce, el equipo identificó 500 especies que realizan actividades como mezcla del suelo, excavación, construcción de madrigueras, pisoteo del terreno y edificación de montículos y presas.

Más de una cuarta parte de estas especies están amenazadas, en declive o presentan tendencias poblacionales desconocidas de las que los científicos saben poco o nada. “Sus procesos geomórficos podrían desaparecer de los paisajes antes de que comprendamos su importancia”, advirtió Harvey.

Los investigadores calcularon cuánta energía invierten estas 500 especies en la transformación de los ecosistemas terrestres y de agua dulce. Según Harvey, los datos sobre la energía que gastan las criaturas en actividades biomórficas son escasos. Los valores existentes varían desde menos del 1% del gasto energético diario hasta más del 40% en especies como las lombrices de tierra, que pasan mucho tiempo excavando. Para 495 especies de fauna silvestre y cinco tipos de ganado (bovinos, caballos salvajes, cabras, ovejas y yaks), el equipo estimó la energía geomórfica colectiva considerando la abundancia global de cada especie y asumiendo que el 1% de su presupuesto energético total se destina a la modificación del suelo.

“Y aun usando ese valor conservador, la magnitud de la contribución de los animales es impresionante”.

“Utilizaron un valor muy sólido y conservador”, afirmó Clive Jones, ecólogo del Instituto Cary de Estudios de Ecosistemas en Millbrook, Nueva York, quien no participó en la investigación. “Y aun usando ese valor conservador, la magnitud de la contribución de los animales es impresionante”.

Los 76,000 gigajulios que los animales silvestres invierten anualmente en la remodelación de la superficie terrestre equivalen a 200,000 temporadas de monzones o 500,000 inundaciones extremas de ríos. Y esta cifra ni siquiera contempla los océanos o las zonas costeras.

El ganado gasta un estimado de 34.5 millones de gigajulios—450 veces más que los animales silvestres—en procesos geomórficos incluyendo el pisoteo del suelo.

Es probable que la estimación de los animales salvajes subestime su impacto total, ya que muchas especies que remueven la tierra, especialmente insectos, aún no han sido descubiertas (Las acciones de animales de gran tamaño, como la excavación de osos o el hozamiento de jabalíes, están bien documentadas). Además, los datos sobre puntos críticos de biodiversidad, como los trópicos, son más escasos en comparación con los de entornos templados del hemisferio norte.

Los investigadores publicaron sus resultados en Proceedings of the National Academy of Sciences of the United States of America.

Características de las criaturas

Ha existido un debate constante entre los geomorfólogos sobre la importancia real de las acciones de los animales, señaló Jones. “¿Se puede medir un efecto neto?” Hasta ahora, la cantidad de datos no es lo suficientemente extensa para responder a esa pregunta, agregó, pero este nuevo estudio representa “una forma muy legítima e innovadora de comenzar a abordar este problema”. Una de las dificultades para contabilizar los efectos de los animales es que la variedad de acciones que realizan supera con creces el número de procesos geomórficos físicos, explicó.

Un análisis completo del impacto de los animales debería incluir los ecosistemas costeros y marinos, donde organismos que van desde gusanos y crustáceos hasta marsopas y peces alteran los sedimentos del fondo marino. De hecho, la Gran Barrera de Coral es la mayor estructura zoogeomórfica de la Tierra, excluyendo aquellas construidas por humanos, señaló Ilya Buynevich, geólogo de la Universidad de Temple en Filadelfia, quien no participó en el estudio.

Los investigadores también podrían analizar cómo diferentes organismos interactúan en ciertos entornos y generan efectos en cascada, sugirió Harvey. Por ejemplo, las actividades de algunos herbívoros modifican la fauna del suelo subterráneo. Otras especies pueden afectar sus ambientes solo cuando alcanzan un umbral poblacional. Los anfípodos que habitan en aguas subterráneas, por ejemplo, pueden mantener la porosidad de los sedimentos de los acuíferos, pero solo si su densidad poblacional es lo suficientemente alta, explicó Harvey. La nueva investigación se centró casi exclusivamente en los efectos de los animales dentro de su rango de distribución natural; futuros estudios podrían considerar los efectos de especies invasoras o introducidas.

Para la mayoría de los científicos, incluso los ecólogos, los procesos no biológicos suelen considerarse “fundamentales”, señaló Buynevich. Sin embargo, el papel de los animales en la transformación del paisaje debería tomarse en cuenta en iniciativas de conservación, como la reintroducción de especies y la restauración ecológica. Además, estos procesos no suelen estar representados en los modelos de evolución del paisaje. Los científicos de la Tierra que buscan las fuerzas que han modelado los entornos a menudo no consideran lo que los animales podrían haber hecho, afirmó.

Por ejemplo, Buynevich investiga los procesos geomórficos en entornos costeros donde los científicos suelen atribuir ciertas formaciones a tormentas intensas o tsunamis para explicar las características que observan. Sin embargo, advirtió, “hay una gran posibilidad de que esas anomalías que observo en playas milenarias… sean nidos de tortugas marinas”. Los científicos deberían, al menos, considerar la posibilidad de que algunas estructuras sean de origen biológico, concluyó.

—Carolyn Wilke (@CarolynMWilke), Escritora de ciencia

This translation by Saúl A. Villafañe-Barajas (@villafanne) was made possible by a partnership with Planeteando and Geolatinas. Esta traducción fue posible gracias a una asociación con Planeteando y Geolatinas.

Text © 2025. The authors. CC BY-NC-ND 3.0
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The cold outer reaches of the solar system are home to a plethora of small worlds, many of which have moons of their own. For a few, the moon is massive enough to make the pair into a binary; the Pluto-Charon system is the most famous of those. And a small icy body named Lempo is a trinary: three objects of comparable mass in mutual orbit.

Now astronomers have identified another possible trinary object, a very distant world known as Altjira (al-TCHEE-ruh), named to honor the creator deity in Arrernte Australian cosmology. Observers discovered Altjira in 2001 and its as yet unnamed moon in 2006. With data accumulated over the past 2 decades, researchers determined the path of the moon doesn’t match what would be expected if it were orbiting a spherical (or mostly so) world.

“Our modeling tells how squished the central object is.”

“When we take images [of Altjira], we just see two objects, and we can track those two objects gravitationally,” said Benjamin Proudfoot, an astronomer at the Florida Space Institute who led the observational part of the project. “We can see that the orbit precesses, and precession is caused by the nonspherical shape of one of the objects. Our modeling tells how squished the central object is.”

In fact, the analysis showed the central object was too squished to be one single body: It is almost certainly two, making Altjira the second known trinary beyond Neptune. And that’s a big deal.

“One of the primary goals of planetary science is kind of understanding how things formed,” Proudfoot said, noting that these trans-Neptunian objects (TNOs) are remnants of the earliest days of our solar system. One major theory explaining the formation of the solar system, known as streaming instability, predicts the formation of a number of trinaries.

“Finding triples like Altjira is really important for telling us how we got here,” Proudfoot explained. “Although this icy debris is in the outer solar system, this was the first step into forming the planets that we have today.”

Proudfoot and his colleagues published their results in The Planetary Science Journal.

One Lump or Two?

Binary systems are common throughout the known cosmos: two objects of comparable mass orbiting each other, such as Pluto and Charon or even Earth and the Moon.

A similar type of system exists where three bodies of comparable mass mutually orbit each other: a hierarchical triple. Lempo, Hiisi, and Paha (named for figures in Finnish mythology) are such a trinary: Lempo and Hiisi form a close pair, with Paha orbiting both in a wider path. Altjira is 44 times farther from the Sun than Earth is; if it is a hierarchical triple, it is too far away, and its inner pairing is too tight for even the most powerful telescopes to resolve. Upcoming observations with NASA’s James Webb Space Telescope (JWST) are unlikely to provide direct evidence, though they will help the indirect case.

Without direct observation, indirect measurements showed Altjira’s companion has a precessing orbit, meaning it traces a sort of spirograph pattern rather than a circle or ellipse. That indicates Altjira must actually be two objects, either in mutual orbit like Lempo and Hiisi or stuck together, like the TNO Arrokoth.

To model the shape and nature of Altjira, Proudfoot and his coauthors—including Maia Nelson, who at the time was an undergraduate student at Brigham Young University in Utah—used detailed motion of the object’s companion and worked backward.

“The most likely thing is [Altjira] is a triple system,” Proudfoot said. “Slightly less likely, but not unreasonable, would be something like Arrokoth with a moon.”

The existence of hierarchical triples helps reveal how the solar system formed from its primordial protoplanetary disk of dust and gas. According to the streaming instability theory, a sort of gravitational drag slowed the larger molecules in that disk, allowing them to clump together into larger aggregates. Some of those objects grouped into binaries, and others grouped into hierarchical triples. But the question remains how stable these trinaries would be over billions of years because many things can separate the outermost member of the triad, including the simple passage of time.

“We don’t have money to send spacecraft to all the objects we think are interesting.”

“A trinary configuration like Lempo favors the streaming instability theory,” said Flavia Luane Rommel, an astronomer at the University of Central Florida who has previously worked with Proudfoot but was not part of the Altjira study. One trinary could be a special case, she noted, but the confirmed identity of two triples means there are likely more that have yet to be detected—lending strong support to the streaming instability theory.

More direct evidence of Altjira’s nature requires further observations.

Although JWST will provide some data, “we don’t have money to send spacecraft to all the objects we think are interesting,” Rommel said.

To study such objects, astronomers in her area of research often use stellar occultations: a sort of miniature eclipse in which the object they want to study passes in front of a star. If Altjira is a trinary, an occultation would result in one eclipse for each object blocking the star. “The thing is, stellar occultations are not in our control, they don’t happen when we want them to,” she said.

Proudfoot noted that Altjira’s unnamed moon could provide data similar to those supplied by stellar occultations, however, because the moon’s orbit takes it between Earth and Altjira’s mysterious inner body, an event called a mutual planetary occultation or, simply, a mutual event.

Watching a mutual event’s subtle fluctuations in reflected light could reveal whether the object is a pair or a lumpy single object like Arrokoth. Mutual events are how scientists measured the properties of the binary asteroids Didymos and Dimorphos before sending the Double Asteroid Redirection Test (DART) mission.

“That is imminently doable,” Proudfoot said. “I am working on getting telescope time right now to observe a mutual event in October of this year.”

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

Citation: Francis, M. R. (2025), Distant icy twins might actually be triplets, Eos, 106, https://doi.org/10.1029/2025EO250149. Published on 18 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Source: AGU Advances

As the climate warms, drought conditions are intensifying in many parts of the world. The effects of hydrological drought on water levels in rivers and other waterways are especially crucial to monitor because they can affect regional agriculture, energy production, economic stability, and public health.

Historical rainfall and river flow data exist from only as far back as a few decades to 200 years, depending on the location, time spans too short to assess long-term hydrological behavior accurately. Climate change adds more uncertainty, as historical data are less likely to correlate with potential future conditions. Tree ring widths, which reflect the dry or wet conditions affecting tree growth annually, provide valuable proxy climate data from before historical recordkeeping began.

Guo et al. combined limited historic river flow observations, climate model simulations, and paleohydrologic reconstructions from tree ring proxy data to examine how hydrological drought has evolved since 1100 CE—and how it may continue changing until 2100 CE—in northern Italy’s Po River basin. This basin supports about 40% of the country’s gross domestic product and 45% of its hydropower, and it has a known history of worsening drought conditions since 2000.

The work revealed agreement between paleohydrologic reconstructions and climate model simulations of past droughts, including some during the Medieval Climate Anomaly (900–1300 CE) and the Little Ice Age (1350–1600 CE). Those droughts lasted nearly 40 years and appeared to be much more extreme than modern droughts. The agreement between the reconstructions and modeling of past conditions provided support for the team’s projections of future drought, according to the authors.

These projections indicated alarming trends, such as river flow possibly dropping below levels seen during those historically dry periods: The team’s models suggested a 10% drop in annual average flow of the Po in the 21st century compared to the average levels recorded between 1100 and 2014. Also, though the models suggested fewer droughts will occur in the 21st century, those that do occur will be 11% longer and 12% more severe as climate change reduces water availability and human activities demand more water.

The researchers note that their findings may help this Alpine region and others like it to adapt to the dryer conditions to come. (AGU Advances, https://doi.org/10.1029/2024AV001393, 2025)

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

Citation: Owen, R. (2025), Modeling the past, present, and future of drought, Eos, 106, https://doi.org/10.1029/2025EO250148. Published on 18 April 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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

Warm western boundary currents play a role in lateral transport of heat, salt, and biogeochemical tracers, including nutrients. When these poleward western boundary currents separate from the coast to the east, they seem to drag biologically productive water from near shore regions to offshore. Cross-shelf lateral flows have, therefore, been considered a cause of offshore phytoplankton blooms. However, these currents generate and interact with mesoscale eddies after they separate from the coast.

Chapman et al. [2025] conduct a series of high-resolution observations to investigate the importance of vertical water motions induced by meso- and sub-mesoscale flows associated with these mesoscale eddies. The results suggest that secondary circulation caused by eddy flows near fronts along the East Australian Current induces the offshore phytoplankton bloom over 100 kilometers. 

Citation: Chapman, C. C., Sloyan, B. M., Schaeffer, A., Suthers, I. M., & Pitt, K. A. (2024). Offshore plankton blooms via mesoscale and sub-mesoscale interactions with a western boundary current. Journal of Geophysical Research: Oceans, 129, e2023JC020547. https://doi.org/10.1029/2023JC020547

—Takeyoshi Nagai, Editor, JGR: Oceans

Text © 2024. The authors. CC BY-NC-ND 3.0
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body {background-color: #D2D1D5;} Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today.

NOAA has quietly reported that they will soon decommission 14 datasets, products, and catalogs related to earthquakes and marine, coastal, and estuary science. According to the list, these data sources will be “decommissioned and will no longer be available” by early- to mid-May.

Though NOAA regularly evaluates its data products to ensure they are still relevant, data sources are usually merged with or replaced by other products rather than outright removed. The agency did this just 7 times in 2024 and 6 times in 2023.

 
Related

• NOAA’s Notice of Changes (16 April 2025)
•  Environmental and Science Groups Sue Trump Admin for Deleting Environmental Justice and Climate Information From Federal Agency Websites (EcoWatch)
•  Get Involved: AGU Science Policy Action Center
 

On social media, scientists are urging their colleagues to access and download these data before they are removed so that scientific analyses can continue and the value of the data is not lost.

The announcement of the removals comes days after environmental and science groups sued the Trump administration for the removal of climate and environmental justice websites and data.

“The public has a right to access these taxpayer-funded datasets,” Gretchen Goldman, president of the Union of Concerned Scientists, said in a statement about the lawsuit. “From vital information for communities about their exposure to harmful pollution, to data that help local governments build resilience to extreme weather events, the public deserves access to federal datasets. Removing government datasets is tantamount to theft.”

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

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. Text © 2025. AGU. CC BY-NC-ND 3.0
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In a few weeks, Earth scientists will launch a satellite that will provide unprecedented, high-resolution coverage of some of the most remote and rapidly changing parts of the world. The NASA-ISRO Synthetic Aperture Radar (NISAR) satellite, a joint mission between NASA and the Indian Space Research Organisation (ISRO), will scan nearly the entire globe twice every 12 days to measure changes in Earth’s ecosystems, cryosphere, and land surface.

“In my eyes, it’s orbiting magic,” said Alex Gardner, a glaciologist at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., and a member of NISAR’s cryosphere science team. NISAR will provide high-resolution radar imagery that will enable scientists to track glaciers and ice, biodiversity, soil moisture and water placement, and land displacements from events like earthquakes and landslides.

“When there’s an earthquake, and you can see displacements from 500 kilometers up that you wouldn’t even be able to notice if you were standing on the ground…that’s orbiting magic,” Gardner said.

Double Radar

NISAR is currently anticipated to launch in June from the Satish Dhawan Space Centre in India. It will be the largest, but not the first, satellite collaboration between NASA and ISRO, explained Paul Rosen, NISAR project scientist at JPL. “We had some other collaborations in both planetary and Earth science, but not at this level of magnitude,” he said.

The satellite will host two synthetic aperture radar (SAR) systems that operate at different microwave wavelengths, one longer (L band, at a wavelength of 24 centimeters) and one shorter (S band, at a wavelength of 10 centimeters). SAR is a technique used to create high-resolution images from lower-resolution instruments. The instruments emit continuous pulses of microwave radiation and use the light that bounces back, as well as the time delay, to create backscatter images.

“We made sure that the two radars could work together,” Rosen said. “They’re highly in sync, and we can turn them on together or operate them separately.”

“It’s got a lot to deliver on, but I don’t feel that nervous about it.”

Unlike visible-light imaging, SAR is not limited by the time of day or the weather, explained Deepak Putrevu, an engineer and colead of NISAR’s ISRO science team at the Space Applications Centre in Ahmedabad, India. “It uses microwaves for imaging, so that that makes it able to penetrate the clouds and to image even during the nighttime.…The SAR technology enables us to have day and night coverage and all-weather imaging capability.”

NISAR’s orbit will cause it to pass over the same locations every 12 days. Because SAR can map an area both as it approaches (ascending orbit) and departs (descending orbit), NISAR will be able to scan each area twice every 12 days. Each space agency provided one of the radar systems, as well as other components of the satellite, the launch system, and the data management infrastructure.

“We jointly operate the mission and jointly do the science,” Rosen added.

“It’s got a lot to deliver on, but I don’t feel that nervous about it,” Gardner said. “Aspects of these technologies have flown before,” he added. For example, the European Space Agency’s Sentinel satellites carry SAR instruments that have helped scientists understand the cryosphere, Earth surface processes, and ecosystems. But NISAR’s dual radar frequency bands are a first for Earth-observing satellites. The systems will be able to detect changes at different physical scales—L band for large structures and S band for smaller ones—as well as provide higher-resolution images together than can be achieved individually.

Global Surface Changes

One of NISAR’s primary science objectives is to observe changes to the cryosphere and glaciers around the world. That’s Gardner’s wheelhouse.

“Glaciers are just these really fantastic living creatures,” he said. NISAR will monitor seasonal growth and retreat patterns of glaciers around the world, with a special focus on those of the West Antarctic Ice Sheet like Pine Island and Thwaites.

On 23 January, a large iceberg broke away from Antarctica’s Brunt Ice Shelf. NISAR’s orbit will help glaciologists monitor Earth’s rapidly changing cryosphere. Credit: Contains modified Copernicus Sentinel data (2023), processed by ESA, CC BY-SA 3.0 IGO

“They just have such large societal consequence that there’ll be a lot of attention there,” Gardner explained. More broadly, he said, those seasonal patterns can be a good predictor of long-term changes in the cryosphere.

NISAR will also be able to observe the vertical displacements of ice sheets, which Gardner said will allow cryosphere scientists to map where floating ice sheets meet grounded ice, a boundary called the grounding line.

“It’s really hard to measure, and it’s been done locally but not really at large scale,” he said. “We can watch that position of that grounding line change with time, which is an indicator of vulnerability” to warming temperatures.

NISAR will also measure global biodiversity and soil moisture. The two radar frequency bands will be especially helpful with this, Putrevu explained. “With forest biomass, the L-band system will be able to see the dense forest with more sensitivity. But when we use the S-band system, you can use it for sparse vegetation, as well.”

The SAR systems will be able to see through crop cover and measure soil moisture, Putrevu added, which will provide key information for farmers and agribusiness. He also highlighted the importance of closely monitoring changes in land deformation, which might suggest imminent earthquakes or landslides.

“All the applications have a societal benefit attached,” Putrevu said. “It gives a great deal of satisfaction that this will actually be useful for society.”

NISAR will map Earth’s global land biomass twice every 12 days. Credit: NASA/JPL-Caltech, Public Domain A Data Deluge

After launch, it will take 90 days for the satellite to conduct its commissioning tests and reach its science orbit. “But as we progress, we’re going to get little peeks behind the curtains that we are going to be so enthusiastic about as we see the imagery start to really mature, and the data processing mature, the data acquisition mature,” Gardner explained. “There’ll be a progression from a first light image to science ready data.”

Every pass of the satellite will provide an order of magnitude more data than past satellites have delivered. Much of the final preparation before launch has involved developing the infrastructure needed to efficiently receive, process, and make available such large quantities of data.

“The sheer volume of new data that we’re going to be dealing with requires the development of novel tools.”

“Once NISAR comes online, the sheer volume of new data that we’re going to be dealing with requires the development of novel tools,” Gardner said. “NISAR is really leaning into cloud architecture” for data storage, availability, and computing, so that users don’t have to download massive quantities of data to individual servers. “Moving data around is one of the largest bottlenecks with missions like this.”

“We have been preparing for the last couple years to get all of our algorithms working really efficiently in the cloud,” Gardner said, “so that when the fire hose of data comes online, we can get in there, plug into that data stream, and benefit from it really early on.”

Putrevu said that scientists and students across India have been participating in workshops since 2014 to learn how to access, process, and produce science from NISAR’s data. “That shows how the community is getting geared up to use the data,” he said. “Everyone is eagerly looking forward to [launch] day.”

Because the volume of information requires such novel processing tools, Gardner cautioned that it might be a year or two before NISAR data yield new scientific outcomes. The mission’s nominal lifetime is 3 years, and once the analysis gets up to speed, discoveries derived from those data will likely continue for decades.

“Without a doubt, it will be a legacy dataset,” Gardner said. “It’s going to be transformational.”

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

Correction 22 April 2025: NISAR’s launch date has been updated.

Citation: Cartier, K. M. S. (2025), “Transformational” satellite will monitor Earth’s surface changes, Eos, 106, https://doi.org/10.1029/2025EO250140. Published on 17 April 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
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From cracking mud to thawing permafrost, fractured terrain is common on Earth and many planetary surfaces. And the geometry of those fractures is influenced by both the presence of water and how long it’s been around, according to researchers. A team has now proposed a model to predict the evolution of fractured terrain through time. These new findings could be used to unravel the history of water on other worlds.

Since the 1960s, spacecraft and landers have been beaming back observations of various solar system bodies, returning hundreds of thousands of images. “The amount of data coming in is overwhelming, and it is mostly pictures,” said Gábor Domokos, an applied mathematician at the Budapest University of Technology and Economics in Hungary.

“From the moment that materials solidify, they start falling apart.”

Many of those images show a process now known to be ubiquitous across the solar system: disintegration. “From the moment that materials solidify, they start falling apart,” said Doug Jerolmack, a geophysicist at the University of Pennsylvania in Philadelphia. The study that Domokos and Jerolmack and their respective graduate students Krisztina Regős and Sophie Silver recently published in the Proceedings of the National Academy of Sciences of the United States of America reflects that sentiment in a poetic first line: “Things fall apart.”

The researchers analyzed images of fractured terrain on Venus, Mars, and Jupiter’s moon Europa and manually traced fractures visible in each. The team focused on 15 images: 4 of Venus, 9 of Mars, and 2 of Europa.

From above, the fracture networks look like mosaics of convex polygons. Those polygons can be characterized by simple geometric properties, including their number of vertices and the number of cracks that meet at each of those vertices (or “nodes”). The team did just that, and there was nothing particularly complicated about that work, Domokos said. “We are just counting.”

Of the more than 13,000 nodes that the researchers tabulated, more than 95% consisted of the meeting of two, three, or four cracks. Previous work in geomorphology has referred to those intersections as T, Y, and X junctions, respectively, on the basis of the letters that they often resemble.

Three Letters, Three Processes

T junctions were the most prevalent in the imagery. That result is consistent with investigations of fractures on Earth and not surprising, Jerolmack said, because these junctions form from a basic process: a newer crack running into an older crack and stopping. “This is the most common pattern of something that just breaks and breaks and breaks,” Jerolmack explained. A mud plain that was once wet and then dried over time would be dominated by T junctions.

Y junctions, on the other hand, were less common and tended to occur in landforms that had experienced alternating periods of drying and wetting, the team showed. Laboratory results support that finding: In 2010, another research group published time-lapse photography of clay undergoing repeated cycles of drying and wetting and uncovered T junctions evolving into Y junctions.

The propagation of a crack through partially, but not fully, healed T junctions tends to produce rounded corners, said Lucas Goehring, a physicist at Nottingham Trent University in the United Kingdom and the lead author of that study. “Over time, that corner will be dragged into a shape that is like a Y.”

Though Y junctions do not necessarily imply the presence of water—these features also form in basalt columns, for instance—they hint that a landscape might have experienced a sustained presence of water, according to the researchers.

X junctions proved to be the rarest of the three. The team spotted X junctions—in which a newer crack runs right through an older crack—only on Europa. “Normally, a crack cleanly separates two surfaces,” Goehring said. But an X junction is evidence that a previous crack healed, thereby allowing a younger crack to propagate across it largely unimpeded. “It’s behaving as if that old crack isn’t there,” Jerolmack said.

Water ice is one such material that heals itself, and Europa is known to be covered in a shell of the stuff. Spotting X junctions implies the presence of frozen water, the researchers concluded.

Making Movies

“We don’t have these kinds of movies, not even on Earth.”

Domokos, Jerolmack, and their students next constructed a geometrical model of fracturing. The goal was to develop mathematical expressions encoding the physical processes involved in forming T, Y, and X junctions and then, on the basis of a single image of a planetary surface, model how an ensemble of fractures would evolve over time.

Playing such a movie back might reveal something about the geological processes underlying crack formation, Domokos said. That’s powerful for understanding not only our own planet but other worlds as well. “We don’t have these kinds of movies, not even on Earth.”

The researchers showed that their model could accurately reproduce the entire range of fracture mosaics they observed. That’s critical to verifying the utility of this model, Jerolmack said. “We built a toy model of the universe of fracturing. The actual universe of crack patterns seems happy to comply.”

Testing this model will require more experimental data showing how real fractures evolve, however, Goehring said. Collecting such data isn’t technically challenging, but it can be laborious: Goehring and his team spent several months observing how clay fractured in response to 25 cycles of drying and wetting. “It’s quite a tedious experiment to do,” he said.

But such a model could shed important light on the solar system’s past, said Nina Lanza, a planetary scientist at Los Alamos National Laboratory in New Mexico who was not involved in the research. For instance, getting a handle on whether water persisted somewhere for a long time says something about the geological environment, she said. “Now we’re getting a more complex picture of a planet over time.”

Domokos, Jerolmack, and their students analyzed all of their fracture mosaics manually. However, future investigations could rely on artificial intelligence and machine learning, which would make it possible to probe not just a handful of fracture mosaics but, instead, thousands.

—Katherine Kornei (@KatherineKornei), Science Writer

Citation: Kornei, K. (2025), Cracks on planetary surfaces hint at water, Eos, 106, https://doi.org/10.1029/2025EO250146. Published on 17 April 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
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Source: Tectonics

Identifying long-term seismic activity patterns is crucial for understanding how fault systems evolve, as well as for estimating the probability of future earthquakes. But seismic records date back only hundreds of years—1,000 years at the most—not long enough to fully understand any given fault’s history. Furthermore, because faults can experience times of high activity alternating with quiet periods lasting millennia, seismic forecasts extrapolating from short time spans may greatly over- or underestimate a fault’s rate of activity.

One approach for studying longer-term seismic activity on a fault, chlorine-36 (36Cl) cosmogenic dating, is used to recover histories that can span more than 10,000 years. As slip along a fault progressively exposes rocks, cosmic radiation interacts with carbonate rocks on the fault surface to form atoms of 36Cl, an isotope of chlorine. Concentrations of the isotope reveal approximately how long different rocks have been exposed, a proxy for when earthquakes happened.

Sgambato et al. used 36Cl cosmogenic dating to assess seismic activity over millennia on three faults in Italy’s southern Apennines, where some of the country’s strongest earthquakes have occurred. They then compared the data with other paleoseismic estimates derived from excavating trenches along a fault and tracing markers to measure its displacement. The researchers also calculated slip rates and related annual earthquake probabilities.

The authors found that all three faults experienced periods of both high seismic activity and dormancy in the past 30,000 years and that estimates of earthquake activity from trenching generally agreed with those derived from 36Cl dating. They noted that their results may help show whether these faults are connected to others in the region.

Their research further indicates that slip on a single fault can account for all the regional extension in a given year. This may indicate that strain can be localized to individual faults at certain times. Because their work uncovered a longer record of the clustering of earthquake activity along these faults, it also has implications for seismic hazard forecasting. (Tectonics, https://doi.org/10.1029/2024TC008529, 2025)

—Nathaniel Scharping (@nathanielscharp), Science Writer

Citation: Scharping, N. (2025), Isotopes unearth history of earthquakes in the Apennines, Eos, 106, https://doi.org/10.1029/2025EO250147. Published on 17 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.