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  • ✇Eos
  • Managed Agriculture Hinders Predictability of Critical Zone Features Alberto Montanari
    Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances The critical zone (CZ) refers to the layer of Earth extending from the bedrock up to the vegetation canopy, including interconnected systems such as river and floodplain corridors, the active soil and root zone, and the near-surface environment where plants interact with the atmosphere. The conservation of the CZ requires a detailed understanding of how it evolves under anthropogenic impacts,
     

Managed Agriculture Hinders Predictability of Critical Zone Features

1 May 2026 at 13:32
Sunrise over a crop field and a small lake.
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: AGU Advances

The critical zone (CZ) refers to the layer of Earth extending from the bedrock up to the vegetation canopy, including interconnected systems such as river and floodplain corridors, the active soil and root zone, and the near-surface environment where plants interact with the atmosphere. The conservation of the CZ requires a detailed understanding of how it evolves under anthropogenic impacts, such as intensive agriculture.

Goodwell et al. [2026] use a data driven approach to relate shifts in the critical zone to indicators of human impact. Their findings deliver innovative knowledge on transitions, drivers, and predictability in many contexts, and support better prediction and management of the critical zone under environmental change.

In particular, the authors find evidence of abrupt shifts in the variability of key features like stream and soil chemistry, land-atmosphere interaction and so forth, which can be attributed to intensive management, for instance due to mechanized planting and harvesting. These human-impacted and naturally appearing regimes in the dynamics of critical zone have implications for understanding processes and making predictions of the status of the critical zone under environmental change.

Data-driven methods include grouping of time-series data with clustering to detect regimes, dimensionality reduction to simplify system dynamics and identify main sources of variability. Credit: Goodwell et al. [2026], Figure 1

Citation: Goodwell, A. E., Saccardi, B., Dere, A., Druhan, J., Wang, J., Welp, L. R., et al. (2026). Detecting regimes of critical zone processes, drivers and predictability with a data-driven framework. AGU Advances, 7, e2025AV002098. https://doi.org/10.1029/2025AV002098

—Alberto Montanari, Editor-in-Chief, AGU Advances

The logo for the United Nations Sustainable Development Goal 15 is at left. To its right is the following text: The research reported here supports Sustainable Development Goal 15. AGU is committed to supporting the United Nations 2030 Agenda for Sustainable Development, which provides a shared blueprint for peace and prosperity for people and the planet, now and into the future.
Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  • ✇Eos
  • Chemical Companies Are Churning Out New PFAS. Where in the World Are They Ending Up? Grace van Deelen
    Seeking Solutions to PFAS Pollution Chemical Companies Are Churning Out New PFAS. Where in the World Are They Ending Up? The Persistence of PFAS A Peculiar Polymer Paired with Sunlight Could Remove PFAS Tracing the Path of PFAS Across Antarctica Pollution Is Rampant. We Might As Well Make Use of It. On a rocky archipelago in the North Atlantic Ocean, staff at the Faroese Environment Agency and the Faroe Marine Research Institute regularly sample tissues from the North At
     

Chemical Companies Are Churning Out New PFAS. Where in the World Are They Ending Up?

1 May 2026 at 03:55
A large fjord with rocky, snow-covered mountains in the background

On a rocky archipelago in the North Atlantic Ocean, staff at the Faroese Environment Agency and the Faroe Marine Research Institute regularly sample tissues from the North Atlantic long-finned pilot whales that roam the waters around the islands. The archive of these samples stretches back to the 1980s and has helped researchers determine the reach of human-made contaminants in the remote marine environment.

Jennifer Sun is one of those researchers. Sun studies PFAS—per- and polyfluoroalkyl substances, commonly known as “forever chemicals”—at Harvard University and is the lead author of a recently published study that analyzed how these toxic chemicals have accumulated in pilot whale tissue over the past 2 decades.

Using samples of whale tissue collected between 2001 and 2023, Sun and her colleagues measured a parameter called bulk extractable organofluorine, which shows the overall amount of organofluorine-containing chemicals (including PFAS) in the tissue. They then used a more targeted analysis able to confirm the identity of 28 specific chemicals out of thousands of possible PFAS formulations.

Three chunks of red and pink whale tissue on a white plastic surface
The pilot whale tissue showed an expected decrease in the concentrations of older PFAS but an unexpected scarcity of newer PFAS chemicals. Credit: Jennifer Sun

The study’s results showed an expected decrease in the concentrations of older PFAS but an unexpected absence of newer PFAS chemicals. This anomaly could be indicative of an emerging question in PFAS research: Where are the newest PFAS going?

Prolific PFAS

There are two general categories of PFAS. The first includes legacy PFAS such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). Chemical manufacturers produced these compounds in the 1970s, 1980s, and 1990s for products including nonstick cookware and food packaging and in industries such as fabric waterproofing, industrial manufacturing, and firefighting.

Legacy PFAS were phased out in the early 2000s, and novel PFAS were made to replace them. The term “novel” is independent of chemical properties and instead refers to when the chemicals’ production began, though novel PFAS typically have formulations meant to reduce their persistence in the environment. For example, many novel PFAS molecules have shorter chains of fluorinated carbons than their legacy counterparts.

Novel PFAS include possibly millions of different chemical structures, and their production and use are increasing globally.

A diagram shows the general structure of a PFAS molecule, which includes a “head group” connected to a chain of fluorinated carbon atoms.
A generic PFAS molecule includes a compound head connected to a tail of fluorinated carbons. Older PFAS generally have longer tails (seven or eight carbons) than newer ones. Credit: Mary Heinrichs/AGU, after https://bit.ly/pennstate-ext-pfas

In the United States and elsewhere, regulatory structures that limit PFAS production target specific chemicals, such that every new formulation by a company must be tested individually before restrictions are put in place. With companies continually conjuring new PFAS formulations—which environmental advocates often call “regrettable substitutions” for their sometimes harmful effects—understanding the fate and transport of novel PFAS is difficult and time-consuming. Research on the behavior of specific PFAS may be a drop in the bucket when millions of potential PFAS, with millions of potential behaviors, pose current and future risks to people and the environment.

Scientists like Sun are determined to untangle how the fate of these new chemicals differs from their predecessors. As Sun expected, the phaseout of legacy PFAS was reflected in the pilot whale tissue she tested. These results are good news; they clearly show that the bans on legacy PFAS are working.

“We’re still finding [older] compounds, but clearly, they are no longer as abundant in the environment as they used to be, which is a positive,” said Bridger Ruyle, an environmental engineer at New York University who studies PFAS and assisted Sun and her coauthors in deciding which methods to use for the new study.

But Sun and her colleagues also expected an overall increase in concentrations of novel PFAS—after all, production of these chemicals is higher than ever, and researchers finally had the analytical tools to catch them.

“The inference is, if it’s not in the whales, and it’s not in the ocean…where is it?”

That wasn’t what they found. Instead, all but two of the emerging PFAS they tested for were virtually nowhere to be seen in the whale tissue, leaving the scientists leading the study to wonder where novel PFAS were accumulating or if instrumentation was limiting their detection.

“We do know that the novel PFAS are being produced, which means they’re going somewhere. Where they are, and how exposed people and other wildlife are, is not as clear,” Sun said.

“The inference is, if it’s not in the whales, and it’s not in the ocean…where is it?” asked Elsie Sunderland, an environmental scientist at Harvard University and coauthor of the new study.

Sun and Sunderland’s question—asking where novel PFAS are going—is one scientists are probing from multiple angles. Those who study particle transport are asking how novel PFAS might travel through Earth’s water and air. Those on the chemistry side of the investigation are deducing how novel PFAS might break down. And those who monitor environments are looking for traces of novel PFAS in various corners of Earth.

The answers to their questions have direct, practical implications for human and environmental health and could indicate whether a growing proportion of harmful PFAS may be ending up in close proximity to humans—where we work and eat and breathe.

A Toxic Legacy

The chemical properties of PFAS have made the chemicals useful since the 1940s. These same properties also make them highly persistent—the most durable types may not break down in the environment for several thousand years.

PFAS are linked to certain cancers and other human health harms. Much of the available data linking PFAS to poor health come from analyses of legacy PFOA and PFOS. They show an association between increased exposure to these chemicals and altered immune and thyroid function, liver and kidney disease, reproductive system disruptions, and more.

Chemical manufacturers phased out production of legacy PFAS after scientific evidence emerged associating PFAS and human health harms, businesses began to lose money in massive lawsuits, and regulations tightened. Novel PFAS were intended to show properties similar to legacy PFAS but were meant to break down more easily in the environment (lower persistence) and accumulate less easily in living tissue (lower bioaccumulative ability), though studies have shown mixed results about whether novel PFAS are actually safer for humans or break down more easily.

Because PFAS production data are often proprietary, scientists who study PFAS, like Sun, must rely on partial inventories of PFAS production or reverse-engineer those numbers from observations in the environment.

“We call it chemical Whac-A-Mole.”

Without a clear list of the chemical structures of novel PFAS, scientists don’t always have the analytical standards necessary for routine detection. And once scientists do understand the behavior of a PFAS chemical, it may be quickly replaced by another, unknown alternative. “We call it chemical Whac-A-Mole,” Sunderland said.

Legacy PFAS tend to have a high affinity for water and typically end up in the ocean, the place scientists refer to as the chemicals’ “terminal sink.” Many legacy PFAS also entered the ocean through atmospheric transport such as rain or snow. But because of the sheer number of chemical formulas and the chemical differences between legacy and novel PFAS, the pathways that novel PFAS take through the environment are less clear.

Tracking the movement and accumulation of novel PFAS in the environment is crucial for understanding how these chemicals may affect ecological and human health.

Still, the science is inconclusive about whether novel PFAS are moving or accumulating differently than their legacy counterparts, whether they have a different terminal sink, and where that terminal sink may be.

Close to Home

One possible answer to the question of the missing novel PFAS may have to do with geography. The chemicals may not have reached pilot whales in the Faroes because something about the new chemistry has led them elsewhere in the environment. To Sun, evidence suggests “that a lot of these novel PFAS, which we know are being produced, may not be transporting out into this more remote environment either at all or as quickly.”

Novel PFAS might be accumulating closer to their sources—and closer to us. “It may simply be that some of the replacement PFAS don’t make it all the way out into the open ocean. But if they are still in the terrestrial environment and the near-coastal environment, then wildlife and people who live close to the sources can be exposed, said Frank Wania, an environmental chemist at the University of Toronto Scarborough.

For example, one study monitored PFAS in coastal beluga whales in Canada’s St. Lawrence Estuary, relatively close to human communities and PFAS manufacturing sources. The study showed increasing concentrations of unregulated novel PFAS in whale tissue from 2000 to 2017, while concentrations of legacy PFAS declined.

The suggestion that novel PFAS are accumulating close to human communities is supported by measurements of PFAS in human tissue, too. Studies show that a high proportion of detectable organofluorine chemicals in human tissue are increasingly unidentifiable, suggesting that some of the novel PFAS production “is in us,” Sunderland said.

Far and Away

Though there are some indications that novel PFAS may be retained closer to human communities, there are also reasons to think some novel PFAS chemistries have resulted in substances that can actually travel farther and more easily than their legacy counterparts.

Anna Kärrman, an environmental chemist at Örebro University in Sweden, said that some novel PFAS may be more easily transported in the environment: “The more novel chemistries are increasing the properties of being very mobile in water, very mobile in the atmosphere, and not necessarily very bioaccumulative.”

The mobility of novel PFAS was on full display in a 2020 study that Sunderland coauthored, in which researchers reported detecting hexafluoropropylene oxide-dimer acid, a novel PFAS chemical more commonly known as GenX, in the Arctic for the first time. GenX, produced by chemical manufacturer Chemours, was meant to replace the legacy compound PFOA. The 2020 study suggested GenX “has already moved quite a bit,” said Rainer Lohmann, a marine geochemist who leads the STEEP (Sources, Transport, Exposure and Effects of PFAS) Center at the University of Rhode Island.

A pulley system mounted on a red beam pulls a small envelope filled with water along a string.
A pulley system mounted on a red beam pulls a small envelope filled with water along a string. Credit: Thomas Soltwedel

The 2020 study also found higher concentrations of PFAS in the Arctic Ocean’s surface water, suggesting that the atmosphere was a particularly important transport pathway for chemical transport. This idea is supported by studies of High Arctic ice caps, which experience contamination only from atmospheric sources, and polar bear tissue. Atmospheric transport of novel PFAS is a subject “at the edge” of PFAS research, Sunderland said.

Wherever researchers look, they’re finding that atmospheric transport is an important pathway by which some PFAS, especially PFAS precursors—chemicals that break down in the environment and become PFAS (either novel or legacy)—move. One idea called the PAART (precursor atmospheric and reaction transport) theory was developed by Scott Mabury, an environmental chemist at the University of Toronto, and others. The PAART theory proposes that many of the harmful PFAS that end up in the most remote parts of Earth are the result of the breakdown of volatile precursor PFAS that have traveled in the atmosphere.

According to Lohmann, atmospheric transport means the ocean remains a terminal sink because many novel PFAS transported in rain or snow will ultimately be deposited in the ocean.

In this scenario, the question of why novel PFAS are not bioaccumulating in Faroese pilot whales remains a mystery. While Lohmann suggests the novel compounds simply don’t accumulate in living tissue, Sunderland isn’t sure that’s the whole story: “As apex predators, the whales are sentinels for what is available and being taken up from the ocean,” she wrote in an email. “Since we don’t see [novel PFAS], it seems unlikely there are large quantities of these chemicals present.”

Profuse PFAS

Another possible explanation for the surprising results of Sun’s whale study could be that there’s just a lag; that is, novel PFAS will end up in Faroe Island pilot whales someday but haven’t yet. Chemicals that could eventually end up in the ocean may be temporarily trapped in soils or recycled back into terrestrial ecosystems via sea spray aerosols, for example.

“The delay we are seeing in the ocean response may in fact be [PFAS] precursors being retained in source zones,” Sunderland wrote in an email. These chemicals may be “taking a really long time to be transformed into more mobile compounds.”

In their pilot whale study, Sun and her colleagues modeled the transport of PFAS to the subarctic and found a 10- to 20-year lag existed between the production of a legacy PFAS compound and its detection in whale tissue. We’re still within that range for many novel PFAS. Sun said she would have expected them to show up in pilot whale tissue by now if they behaved like their legacy counterparts, though it’s possible that it has taken time for the volume of novel PFAS production to ramp up, increasing the time it would take for the substances to be detected in tissues.

A group of whales’ fins breach the surface of the water.
The anomaly documented in the pilot whale study has led researchers to call for more investigation (and perhaps greater regulation) of novel PFAS. Credit: Bjarni Mikkelson

Still, the number of possible novel PFAS chemistries—again, there could be several million different compounds—makes it difficult to generalize how these new substances are, as a group, moving through the environment. “Because the exact structures of all [novel] PFAS remain unknown, some compounds may simply not be captured by the methods used,” Heidi Pickard, an environmental engineer at the consulting firm Ramboll and coauthor on the new whale study, wrote in an email.

Another reason novel PFAS are harder to study is that companies release lower concentrations of more kinds of the chemicals, rather than the “monstrously high” emissions of some legacy PFAS in the 1970s–1990s, noted Mabury, who was not involved in the new pilot whale study.

A New Regulatory Approach

According to Sun and Sunderland, cataloging differences between novel and legacy PFAS misses the broader point: We simply need to produce less PFAS. We’ve known for decades that PFAS harm human health, and some scientists have even argued that humans’ continual production and release of novel chemical compounds could drive Earth beyond a “safe operating space.”

“Researchers are critical for exposing the problem. But that, to me, is not the central issue here. The central issue here is a societal issue.”

Where scientists probe next may be less urgent than how policymakers decide to tackle the PFAS problem, Sunderland said: “Researchers are critical for exposing the problem. But that, to me, is not the central issue here. The central issue here is a societal issue.”

Chemical manufacturers are actively creating novel PFAS all the time. Kärrman, for example, has noticed patent applications for PFAS compounds with chemistries that “are nothing like we have seen before” that may start entering our environment in 5 or 10 years.

To Kärrman, that’s a reason for governments to push for chemical regulation based on properties such as persistence and bioaccumulation, rather than the chemical-by-chemical formula used in most countries, including the United States.

Such an approach has gotten traction in Europe via a proposal by the European Chemicals Agency to restrict the entire class of PFAS chemicals. The proposal is still under evaluation, and a final decision is expected by the end of the year.

In the United States, PFAS regulation and remediation are a key aspect of the Trump administration’s Make America Healthy Again movement, according to the EPA, and the federal government and some states already limit the concentrations of individual PFAS in drinking water. However, the EPA also said it planned to weaken some of those limits last year.

“We’re in a cycle of picking these regrettable alternatives [to legacy PFAS] and then figuring out that it was regrettable decades later,” Sunderland said. “We’re never going to catch up using this chemical-by-chemical approach.”

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

Citation: van Deelen, G. (2026), Chemical companies are churning out new PFAS. Where in the world are they ending up?, Eos, 107, https://doi.org/10.1029/2026EO260136. Published on 30 April 2026.
Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  • ✇Eos
  • As the Coal Industry Fades, Life Expectancies in Coal Country Shift Grace van Deelen
    Want to see more reporting from Eos in your Google search results? Click the button below to make Eos a preferred source. Go to Google The coal industry can damage human health in myriad ways via dangerous working conditions and harmful pollution. But the income opportunities offered by the industry can also provide much-needed stability for certain communities, such as those in Appalachia’s coal country. “Being employed is good for your health, but environm
     

As the Coal Industry Fades, Life Expectancies in Coal Country Shift

30 April 2026 at 12:56
A foggy mountain scene at sunset. In the right-hand corner, a railroad leading to a small building can be seen.

The coal industry can damage human health in myriad ways via dangerous working conditions and harmful pollution. But the income opportunities offered by the industry can also provide much-needed stability for certain communities, such as those in Appalachia’s coal country.

“Being employed is good for your health, but environmental pollution is bad for your health, and these two things are operating at the same time in some communities,” said Mary Willis, an epidemiologist at Boston University.

The industry, though, is changing. Total coal production in the United States peaked in 2008, and the number of miners has steadily dropped since then.

A graph shows total, underground, and surface production of coal in millions of short tons alongside the number of coal miners from 1949 to 2023.
Total coal production peaked in the United States in 2008, after which the number of coal miners declined, too. Credit: Thombs et al., 2026, https://doi.org/10.1111/ruso.70034, CC BY 4.0

A new study coauthored by Willis and published in Rural Sociology delves into the effects of this decline on life expectancies across the United States and in Appalachia in particular. The results show that a disappearing coal mining industry has mixed effects on health, highlighting the importance of a “just transition”—a shift away from coal mining and toward clean energy that also prioritizes decent work opportunities for those left without a job.

“How do we balance these two conflicting priorities?” Willis said.

Delving into the Decline

Coal production and consumption are linked to many human health harms, including heart disease, asthma, lung cancer, mental illness, and more. But how those health impacts intersect with the broader economic effects of mining has not been well studied.

In the new study, the research team analyzed the effects of the declining industry through the lens of the social determinants of health, or how social structures influence health outcomes.

A table shows the life expectancy outcomes of the effects of three pathways by which coal mining impacts health.
Researchers analyzed how coal mining impacts life expectancies via three pathways: production, mining labor time, and employment. Credit: Thombs et al., 2026, https://doi.org/10.1111/ruso.70034, CC BY 4.0

To study these effects, the team compared coal mining data from the U.S. Energy Information Administration to life expectancy data from the Institute for Health Metrics and Evaluation at the University of Washington from 2012 to 2019. Life expectancy is a metric that can be responsive to subtle changes in the environment, Willis explained. For example, the decommissioning of a coal-fired power plant a few miles away from a community may not affect residents’ day-to-day life but probably affects the scale of life expectancy across the population.

In coal-producing counties across the United States, the average life expectancy was 1.6 years lower than that in non-coal-producing counties. But the declining coal industry had more nuanced impacts on health in Appalachian communities, the researchers found. As coal production fell and miner labor hours decreased, life expectancy increased. But as the number of jobs available decreased, life expectancy decreased, too.

The findings suggest that the employment and associated economic impacts of a waning coal industry harm health. Previous studies documented similar increases in mortality in other regions where the fossil fuel industry has declined. Such research has indicated that these increased mortality rates may be partially driven by “deaths of despair” from drug and alcohol use and suicide related to economic distress. The association of these factors with mortality rates in coal country, the authors suggest, may be an area for future study.

Understanding that coal mining is associated with some positive economic and health effects is “an important perspective for understanding the sector as a whole,” said Lucas Henneman, an environmental engineer at George Mason University who was not involved in the new study. “It’s a really interesting piece of work.”

“This is just a really complex story that hasn’t been told yet—putting health into the context of these just energy transitions,” Willis said.

The complex reality of the coal industry extends beyond Appalachia. Most of the pollution related to the coal industry consists of toxins released when coal is burned, meaning those who bear the brunt of coal’s health impacts may not be located where coal is mined, Henneman said.

In fact, a 2023 study by Henneman and others found that before 2009, a quarter of all air pollution–related deaths of people on Medicare were attributable to coal burning. From 2013 to 2020, that number dropped to 7%, alongside a drop in coal consumption. A complete picture of how the coal industry affects health should also consider how pollution travels beyond coal country—where it’s burned, how it’s transported in the air, and who ultimately breathes it in, he said.

A Just Transition

“The question is how to provide [jobs] in a way that provides the same level of stability, same kind of income benefits, and isn’t too much of a shock to [communities’] way of life or sense of identity.”

The economic activity of a mine, through direct employment as well as businesses reliant on the mine and miners, “chases away other opportunities,” making the mine the economic backbone of the area, said Jonathan Buonocore, an environmental health scientist at Boston University and a coauthor of the new study. The concept of a just transition aims to ensure that employment opportunities in the wake of the coal industry’s decline reach these communities.

“The question is how to provide [jobs] in a way that provides the same level of stability, same kind of income benefits, and isn’t too much of a shock to [communities’] way of life or sense of identity,” Buonocore said.

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

Citation: van Deelen, G. (2026), As the coal industry fades, life expectancies in coal country shift, Eos, 107, https://doi.org/10.1029/2026EO260134. Published on 30 April 2026.
Text © 2026. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  • ✇Eos
  • Antibiotic Resistance Might Get a Boost from Droughts Javier Barbuzano
    The spread of antibiotic resistance, a growing threat to global health that causes millions of deaths annually, is typically blamed on the overuse of drugs in hospitals and in the food industry. However, a new study published in Nature Microbiology suggests that normal geological processes could be accelerating the development of new resistances. Soil microorganisms naturally produce antibiotics as a form of chemical warfare to compete with each other. When soils dry out, these natural compo
     

Antibiotic Resistance Might Get a Boost from Droughts

29 April 2026 at 13:19
A forest on a mountainside has mostly green trees, with sprinkles of autumn red and yellow. A brown mountain is in the distance.

The spread of antibiotic resistance, a growing threat to global health that causes millions of deaths annually, is typically blamed on the overuse of drugs in hospitals and in the food industry. However, a new study published in Nature Microbiology suggests that normal geological processes could be accelerating the development of new resistances.

Soil microorganisms naturally produce antibiotics as a form of chemical warfare to compete with each other. When soils dry out, these natural compounds become more concentrated because there is less water to dilute them. Like a dosage increase, this concentration can create a harsher environment, killing sensitive microbes and sparing those with the capacity to resist. This phenomenon, in turn, is an evolutive driver that favors the appearance of new and more effective resistance genes.

“If you have more antibiotics in your environment, only the organisms that can withstand it…can resist it.”

To test whether this mechanism is having real genetic effects, Xiaoyu Shan, a microbial ecologist and postdoctoral researcher at the California Institute of Technology (Caltech), and colleagues looked at soil samples under controlled conditions as the samples transitioned from a wet state to a desiccated one. They found that as the soil dried, the presence of genes related to antibiotic production and resistance spiked, suggesting that drought leads to a rapid escalation in the subterranean biological arms race. Importantly, they did not look for pathogenic bacteria specifically, only for resistance genes, which can be present in a variety of microbes, whether those microbes are pathogenic or not.

“Drought leads to this elevation of antibiotic producers and bacteria that are resistant,” said team member Dianne Newman, a professor of biology and geobiology also at Caltech. “It’s a pretty simple idea: If you have more antibiotics in your environment, only the organisms that can withstand it…can resist it.”

Alternative Explanations

However, there could be other potential explanations for the observed increase in antibiotic-producing and antibiotic resistance genes, according to Enrique Monte, a microbiologist at the Universidad de Salamanca in Spain who wasn’t involved with the new study. For instance, arid soils are naturally more diverse than humid soils, making it common to find a more diverse gene pool in the ground, Monte said. In addition, the mere presence of antibiotic genes might not result in an actual release to the environment, or a release could happen in dosages that are too small to cause noticeable effects. “There are antibiotics that are volatile; they escape into the air, so they never reach a therapeutic concentration to kill others,” Monte said.

The authors, however, took some precautions to show that the increase in antibiotic resistance genes was actually a biological response to environmental stress. For instance, they also tracked other genes that should remain unaffected or decline under desiccation. As expected, genes that are needed for basic survival remained stable, while genes responsible for bacterial movement declined in dry soil, where mobility is restricted. Even some species that were not favored by desiccation saw an increase in resistance-related genes, “which is even stronger evidence,” Shan said.

Geographic Limitations

As the researchers combed through publicly available metagenomic data libraries, they had to select collections with strict control of all variables and in which the only changing factor was water content. That limited the analysis to five locations: two grasslands and a sorghum field in California; a forest in Valais, Switzerland; and a wetland in Nanchang, China.

The scarcity of locations might limit how extrapolable these results are, said Fiona Walsh, a microbiologist at Maynooth University in Ireland who was not involved with the work. “There are thousands of high-quality metagenomes available online with excellent metadata. I would really like to see a comparison where they apply their analysis to a broader map of global metagenomic data to see if they reach the same conclusions,” she said.

From the Soil to the Hospital

Drier regions consistently showed a higher number of resistant bacteria cases in hospitals, even after adjusting for confounding factors such as local income.

The study also suggests that dry soils might be a hidden driver of clinical cases of antibiotic resistance worldwide. The authors combined hospital data on the number of cases of resistant infections from 116 countries with the local aridity index, which measures temperature and precipitation, for each location. They found a strong correlation: Drier regions consistently showed a higher number of resistant bacteria cases in hospitals, even after adjusting for confounding factors such as local income.

However, the authors admitted that this is only a correlation effect and doesn’t prove causation. “It motivates follow-up research to see how environmental concentration weighs against human overuse and poor stewardship,” Newman said.

Even this correlation could be a stretch, according to microbiologist Sara Soto, head of the Global Viral and Bacterial Infections Programme at the Instituto de Salud Global de Barcelona. At the end of the day, she said, the authors have soil data from only five locations in three countries, and they are not tracking the specific bacterial varieties that make people sick, only resistance genes.

For the thesis to be solid, Soto said, the ideal approach would have been to contrast hospital strains from a specific area with soil data from that same region during the same drought episode. “Making such a vast inference—that what happens in the soil of one location affects what happens in a hospital elsewhere—is a big leap,” she said.

The authors, however, point out that resistance genes from soils can eventually make their way into human pathogens. Microbes have the capacity to share genetic material across species—a process known as horizontal gene transfer. In their analysis, the team identified specific resistance sequences that appeared to have been transferred between soil bacteria relatively recently, perhaps within the past decade. How they are reaching hospitals remains a matter for a future study, they said.

As droughts increase in numerous regions in the face of climate change, this selective pressure within soil ecosystems is expected to intensify. Though these findings do not show that drought directly puts drug-resistant pathogens in hospitals, they still suggest that a drying climate could set the scene for an increase in antibiotic resistance, the researchers report.

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

Citation: Barbuzano, J. (2026), Antibiotic resistance might get a boost from droughts, Eos, 107, https://doi.org/10.1029/2026EO260132. Published on 29 April 2026.
Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  • ✇Eos
  • Tracing the Path of PFAS Across Antarctica Rebecca Owen
    Seeking Solutions to PFAS Pollution Chemical Companies Are Churning Out New PFAS. Where in the World Are They Ending Up? The Persistence of PFAS A Peculiar Polymer Paired with Sunlight Could Remove PFAS Tracing the Path of PFAS Across Antarctica Pollution Is Rampant. We Might As Well Make Use of It. Per- and polyfluoroalkyl substances (or PFAS) have been widely used in thousands of common nonstick, waterproof, or stain-resistant products since the 1950s. These “forever c
     

Tracing the Path of PFAS Across Antarctica

27 April 2026 at 13:16
An iceberg sits in a rough, partially frozen sea near Antarctica.

Per- and polyfluoroalkyl substances (or PFAS) have been widely used in thousands of common nonstick, waterproof, or stain-resistant products since the 1950s. These “forever chemicals” do not break down easily: PFAS make their way into the air, soil, and water, as well as into human and animal bloodstreams and to some of Earth’s most pristine environments. They have been detected even in Antarctica, despite its reputation as a relatively untouched landscape far from the types of products—fast-food wrappers, firefighting foam, nonstick cookware—that contain PFAS.

Research into how PFAS arrive in Antarctica is limited, and most tends to focus on the continent’s coasts, rather than its interior. A new study published in Science Advances aimed to fill some of these gaps by examining PFAS accumulation across a 1,200-kilometer stretch of Antarctica, from the snow pits of Zhongshan Station in East Antarctica to the 4,093-meter peak of Dome A. By examining layers of snow collected from the coast to the interior, researchers sought to better track and understand how PFAS levels vary by location and how these forever chemicals have been able to travel long distances through the upper atmosphere to be deposited in remote regions.

“For substances to get there, they have to be able to transport long distances,” said Ian Cousins, a chemist at Stockholm University and one of the study’s authors. “We know PFAS are very persistent, so that helps. By looking at the patterns of the PFAS contamination in the samples, it gives us clues as to how they’re transported.”

PFAS Arrive by Air and by Sea

Along the 1,200-kilometer route, researchers from the Chinese Academy of Sciences collected 39 snow samples at 30-kilometer intervals, scraping the first few centimeters of snow from the surface to analyze for traces of PFAS.

Zhongshan Station sits near Prydz Bay, and there, researchers collected snow from a 1-meter-deep pit, with samples taken every 5 centimeters. At Dome A, the summit of the East Antarctic Ice Sheet, samples were collected at 10-centimeter intervals from another snow pit; this one was 3 meters deep, providing information about the past several decades of PFAS use.

“It’s quite interesting that we see the historical production record of PFAS in this pit on the top of this mountain in Antarctica,” said Cousins.

PFAS pollution arrives in Antarctica in two ways: via upper atmospheric transport and sea spray. Some PFAS are formed in the atmosphere when volatile precursor chemicals like fluorotelomer alcohols used in textile and paper products break down through reactions with sunlight and oxidants into more stable compounds. The resulting PFAS are later deposited into the snow and ice through precipitation.

Storm winds near the coast create sea spray. “When you have waves, it makes bubbles in the ocean. When the bubbles burst, these sea spray aerosols can be super enriched with PFAS. This has been shown to be a very important transport route,” Cousins said.

To distinguish between sources, researchers measured sodium in the snow to trace the ocean’s salty influence. Sodium levels decreased farther inland, reflecting the fading influence of sea spray toward the interior of the continent. But surprisingly, PFAS concentrations actually increased moving from the coast into the interior.

“That was kind of a bit counterintuitive to me,” explained Cousins, who said he expected PFAS levels to be highest near the coast. “You see the opposite, actually.”

The inland increase is likely explained by higher snowfall totals in the coastal regions, which lead to PFAS concentrations becoming diluted. Inland, where snowfall is lower, even small amounts of PFAS can result in relatively higher concentrations within snow samples.

Additional factors shape PFAS distribution. PFAS levels are higher at the onset of precipitation events when they are rapidly removed from the air. Temperature inversions, too, can trap chemicals. In coastal areas, PFAS are more influenced by sea spray in the winter, whereas stronger sunlight drives the degradation of atmospheric precursors into PFAS in the summer months.

PFAS Presence at Both Poles

This new study also offers implications for the way that PFAS circulate globally. Though industrial activity in the Northern Hemisphere contributes most heavily to PFAS emissions, large-scale atmospheric circulation allows these compounds to reach polar regions. Rapid transport in the upper troposphere may act as an efficient pathway to shuttle PFAS across both hemispheres before they are deposited in the cold, remote regions at both ends of Earth.

“This completes the global picture with agreeing measurements at both poles, solidifying our understanding of the global distribution and drivers of PFAS contamination.”

Even though PFAS levels are higher in the Arctic, both polar regions show similar trends in PFAS concentrations since the 1990s. “It really matches decades of the same records that have been reported from the Arctic,” said Cora Young, an atmospheric chemist at York University, who was not involved in the new study.

“This completes the global picture with agreeing measurements at both poles, solidifying our understanding of the global distribution and drivers of PFAS contamination. The role of CFC [chlorofluorocarbon] replacements, changes in regulation, all of these things are important in the Northern Hemisphere and also the Southern Hemisphere,” said Young.

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

Citation: Owen, R. (2026), Tracing the path of PFAS across Antarctica, Eos, 107, https://doi.org/10.1029/2026EO260129. Published on 27 April 2026.
Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  • ✇Eos
  • Hurricane Helene Ravaged Farmers’ Topsoil. They’re Still Fighting to Build It Back. Irina Zhorov
    This story was produced by Grist and the Food & Environment Reporting Network, a nonprofit news organization. Sign up for Grist’s weekly newsletter here. Will Runion’s 736-acre cattle and hay farm is tucked into a horseshoe bend of the Nolichucky River in northeast Tennessee. On the morning of Friday, September 27, 2024, he was in the middle of two big projects: building a riverfront campground on his land to bring in tourists and income, and cutting the last of the season’s hay. Hurrica
     

Hurricane Helene Ravaged Farmers’ Topsoil. They’re Still Fighting to Build It Back.

23 April 2026 at 12:52
Aerial view of muddy flood debris across fields in North Carolina

This story was produced by Grist and the Food & Environment Reporting Network, a nonprofit news organization. Sign up for Grist’s weekly newsletter here.

Will Runion’s 736-acre cattle and hay farm is tucked into a horseshoe bend of the Nolichucky River in northeast Tennessee. On the morning of Friday, September 27, 2024, he was in the middle of two big projects: building a riverfront campground on his land to bring in tourists and income, and cutting the last of the season’s hay. Hurricane Helene had been arcing up from Florida toward the Appalachian Mountains, carrying heavy rain, and the river was high. Even though the banks seemed to be holding, he decided to move some of his cows and equipment to higher ground.

But the river kept rising. At about 11 a.m., the brown water topped its banks. He and his fiancée, his son-in-law’s parents, and neighbors scrambled to salvage what farm equipment they could, but they were nearly trapped when the quickly expanding river flowed into a low-lying area behind where they were working, cutting them off from dry land.

By afternoon, the river had swollen to some 1,200 feet wide—nearly 10 times its usual size. It “looked just like a lake,” Runion said. Trees snapped in the swift current and neighbors’ barns, roofs, hay bales, and household debris swirled by. The water swallowed Runion’s hay equipment and sent the little white house he’d planned to use as the new campground’s office sailing across a field.

At around 8 p.m., the Nolichucky finally crested and started to recede. Runion found a third of his fields covered in debris, dead fish, and tomatoes from upstream vegetable growers. The flood had gouged two holes the size of football fields in his hay pastures, down to a depth of 12 feet. Other sections of the farm were buried in up to 8 feet of sand or silt.

(left) An overhead view of a farm shows a landscape washed over with sand. (right) An overhead view of a grassy landscape shows two patches of eroded dirt.
Flooding from Hurricane Helene brought massive damage to Will Runion’s farm, eroding the land in some places and washing up feet of sand on agricultural fields in other sections. Courtesy of Bryan LeBarre, via Grist

Helene dropped up to 30 inches of rain on southern Appalachia, causing historic flooding and landslides in parts of North Carolina, South Carolina, Tennessee, Georgia, Kentucky, and Virginia—a largely rural region where agriculture is a vital economic driver and cultural cornerstone. The mountains make it hard to spread out here, so farms tend to be small, and many growers use flood-prone bottomland because it is flat and fertile. But floods of this magnitude hadn’t hit here in generations. In North Carolina alone, Helene caused an estimated $4.9 billion in damage to the state’s agriculture sector. In Tennessee, agricultural losses were estimated at $1.3 billion. Thousands of farmers lost crops, tools, machinery, barns, buildings, animals, and fences.

“When you see 4 feet of sandy soils on top of your topsoil, you know that’s going to be a challenge. That was overwhelming.”

More than a year later, growers are also contending with the loss of something more vital, and more difficult to replace: their soil.

Runion knew immediately that his livelihood was ravaged. Without good soil, a farmer can’t farm. “When you see 4 feet of sandy soils on top of your topsoil, you know that’s going to be a challenge,” he said. “That was overwhelming.”

He sent drone footage of the damage to Forbes Walker, an environmental soil specialist with University of Tennessee Extension. “How do you fix this?” he asked.

“I don’t know,” Walker recalled thinking when he got Runion’s email. “How do we fix this?”

Over millennia, floods helped build the fertile land that farmers depend on. But today, climate change is driving more powerful and unpredictable storms. One study found that rainfall associated with Helene was 10 percent heavier due to man-made climate change. Research by the U.S. National Science Foundation suggests that what scientists call “100-year storms” will become three times more likely, and 20 percent more severe, over the next 50 years. What’s more, there’s little solid information about what happens to soil during a flood, or what to do when a farm’s soil is eroded or covered with material from elsewhere—its nutrients washed away and microbial communities disrupted. It’s a blind spot that is becoming more of a liability as storms like Helene become more common.

“None of us had ever seen anything like this before or responded to an emergency like that,” said Stephanie Kulesza, a nutrient and soil scientist at North Carolina State University. “And so we weren’t really prepared for recommendations to provide to producers.”


Soil can take thousands of years to form. Rock is weathered and slowly dissolves into smaller and smaller pieces. As dead leaves, animals, trees, and other plants decompose, they add organic matter and nutrients to the rock. Microorganisms establish themselves in the mix, driving nutrient cycling, aiding with decomposition, and stimulating plant growth; then worms and bugs, like beetles and ants, burrow in the mixture, aerating it. For soils to work well for agriculture, they need the right structure—airy enough to allow water to enter and move through, but not too quickly or too slowly—and sufficient biological and chemical richness, including nutrients like nitrogen, phosphorous, and potassium, to nourish crops.

Farmers use synthetic or natural fertilizers to ensure their soil has enough nutrients. They can also introduce practices like no-till—farming without plowing up the ground—to maintain the physical properties of their dirt. Topsoil, the rich, uppermost layer with the most available nutrients for crops, tends to make up less than a foot of the entire soil profile, but it’s crucial for agriculture.

A man stands in a rectangular dirt pit, about the same height as himself, which is surrounded by yellow caution tape.
Soil scientist Forbes Walker visits Will Runion’s farm in 2025, examining the deep sandy deposits left behind by Hurricane Helene. Credit: Raffe Lazarian/University of Tennessee Institute of Agriculture via Grist

Helene’s floodwaters either washed away significant topsoil or deposited new sediment on top of it on thousands of farms. Some, including one of Runion’s neighbors, saw their fields stripped down to bedrock, or river rock. Runion and others woke to pastures blanketed by feet of sand or stone.

When topsoil is washed away, the necessary nutrients for growing go with it. And when topsoil is covered with sand, farmers can’t get to it. Both scenarios can significantly alter the land’s usability. Topsoil can take decades or centuries to develop, and sand lacks both organic matter and the physical structure to hold water and nutrients. “These aren’t soils yet,” said Kulesza of what Helene left on Runion’s and other farmers’ land. “They are in their infancy now. The clock has been reset.”

Runion had cared for his soils, working to eliminate weeds, adding fertilizer to keep nutrient levels ideal, and lime to control pH. “They were our way of life,” Runion said. “They were our income.”

After the storm, from October to April, he removed debris, bulldozed sand off his fields to get closer to the topsoil, filled holes, and graded uneven land. Crews from the Federal Emergency Management Agency removed and shredded downed trees. He applied for government relief and received close to $1 million in state and federal aid. Runion said he could have easily used all of that money replacing equipment and paying for cleanup labor, fertilizer, and fuel, but he’s trying to stretch the money as much as possible.

By June, it was time to mow the fields that hadn’t flooded. He managed to put up enough bales of hay to feed his herd of 125 cattle, but not enough to sell. In a normal year, hay sales made up about a third of the farm’s income. With months of work behind him and his flooded land still too sandy and generally depleted, he realized the recovery would be a slog.

Runion returned to work on the campground, which he hoped would diversify the family’s earnings. The longer-term plan included a music venue and some hiking trails, and to host weddings and corporate events. After the storm, finishing it took on new urgency. He chose a new spot, about 450 feet upland from the river, and began clearing enough land for 45 camping sites.

One environmental soil specialist described the academic literature on flood-damaged soils as “thin.”

Runion also prepared a parcel of land for Walker, the extension soil specialist, to run tests that could guide his recovery. Last November, soon after the one-year anniversary of Helene, Walker showed me around Runion’s farm.

Working with students, Walker established four experiments over about 300 test plots. He’s looking at how different soil amendments—hay, wood chips, poultry litter, and a charcoal called biochar, to help the soil hold water and fertilizer; and Triple 19, a common plant food with equal parts nitrogen, phosphorous, and potassium—affect the growth of wheat and fescue grasses.

When I visited, some of the plots remained mostly bare while, in others, tufts of green had sprouted. “We actually got some stuff to grow,” Walker said.

He described the academic literature on flood-damaged soils as “thin.” While some research and case studies exist on how agricultural soil recovers after a flood, there are few systematic investigations like the one Walker is conducting—on what works, and what does not—particularly in Appalachia, where floods of this magnitude have been historically rare.

When so-called atmospheric rivers spawned devastating floods in the Pacific Northwest and southwestern British Columbia in 2021, Aimé Messiga, a Canadian soil research scientist at the Agassiz Research and Development Centre, found a similar “scarcity of data.” He conducted a detailed review of the existing research and concluded that there was limited long-term monitoring, little understanding of how floods affect nutrients and microorganism communities in the soil, and uncertainties about what the actual impacts of floods on agriculture and crops are. Complicating everything is the variability between different farms, soils, and crops.

“You need decades of accumulated data in order to be able to predict what will happen. We don’t have those data.”

“You need decades of accumulated data in order to be able to predict what will happen,” Messiga said. “We don’t have those data.”

Today, some researchers are attempting to replicate flood conditions in labs to better understand, but field work is rare, Messiga said. There’s little money for it—and in the U.S., the Trump administration has cut funding for climate-related research. In addition, “many among us still look at these events as random,” Messiga said. “They’re not random. They will keep occurring.”


Since 1980, 45 flooding events have caused damages over $1 billion each in the U.S., with more than half of those occurring in the past 15 years. In 2024, flooding in the upper Midwest drowned crops. Repeat events in central California damaged agricultural operations from winter 2022 to spring 2023. Flooding along the Mississippi River in 2019 reduced crop planting by millions of acres. There also have been numerous smaller or more localized floods. One study found nearly 75,000 flash floods in the contiguous U.S. from 1996 to 2017, with increasing frequency in the past 22 years. Flooding frequency and strength is predicted to rise in the years to come due to climate change—a warmer atmosphere holds more moisture and leads to stronger rain events—and poor land-use management.

Scientists are also starting to study a new type of event, called “weather whiplash,” when sudden changes occur from one extreme to another, amplifying the effects of the disaster. In Texas in 2025, a flood came after prolonged drought, causing widespread destruction.

For farmers, the effects of flooding on soil may linger for years after the disaster. In 2011, the Missouri River flooded states in the Upper Midwest, including thousands of acres of farmland. Fields were swamped for months with up to 20 feet of water. When the water finally receded, those fields were covered with anywhere from 2 to 20 feet of sand; other fields had washed out holes up to 70 feet deep. It looked like the surface of the moon, said John Wilson, a now-retired educator and agricultural expert who served Burt County, Nebraska, which was particularly hard-hit. “It was just bare soil,” he said. “There was no crop residue whatsoever.”

Wilson led teams that sampled the soil and helped farmers build back. He found that levels of nitrogen and organic matter were low in flooded soils, and fertility suffered when farmers planted their crops. Over about five years, fertility generally improved, but not everywhere. “If you went out today and did a yield map, you could still tell exactly where the erosion was because those areas are not as productive,” Wilson said.

Yield is money for farmers, who already navigate thin margins and, often, years without any profit at all. North Carolina’s strategic plan for agriculture recently enumerated just how thin: Of the state’s “42,500 farms, only 8,000 produce annual gross sales that exceed $100,000 annually. The overwhelming majority … some 23,400, gross less than $10,000 in sales, with only around 40 percent of the farms in the state having a positive net income in 2022.”

As floods increasingly wreck farmland, more researchers are starting to focus on understanding the effects of the floods and how to address them. Most of that work is happening in Asia, Messiga said. But a study in coastal North Carolina, where hurricanes regularly land, found that after a storm there was less organic matter in the soil, including carbon, and a disruption of microbial activity and nutrient cycling. The ground also absorbed water less readily.

Coastal flooding is also driving saltwater into the soil of farmland, making it more saline and unable to sustain crops. A North Carolina State University team has been developing test kits for farmers to sample the salinity of their soils, as well as a set of recommendations for keeping their soil viable. Such local work is important because soils vary greatly from place to place, and findings are not often easily transferable.

A white agricultural tent lies on the ground, having been wiped out by a flood. Green trees line the area.
Nicole DelCogliano’s farm near Asheville, North Carolina, was wiped out almost entirely by floods from Hurricane Helene in 2024. Courtesy of Nicole DelCogliano via Grist

For now, in the wake of Helene, farmers are relying largely on trial and error to build back what was lost. Nicole DelCogliano has been farming vegetables, flowers, and livestock with her husband on 50 acres on the South Toe River, near Asheville, North Carolina, for 25 years. Helene washed away her barn, tractor, and other infrastructure. Of her 6 acres of vegetable fields, one was covered with several feet of sand, another got a foot, and a third field suffered extensive erosion.

“Our entire operation was wiped out, essentially,” she said.

“It’s not something that can be fixed overnight. This is a long process.”

With the help of some friends with tractors, DelCogliano cleared her main field and spread compost and lime on everything. “There was a mix of guidance about what you should do, like should you disturb the soil, should you not?” she said. “At an instinctual level, we just felt like we got to get the soil covered, we got to get something in the ground.” They sowed rye, a dependable cool season grass, as a cover crop, to protect the soil from erosion and add nutrients.

Karen Blaedow, an agricultural educator in Henderson County, North Carolina, said farmers should expect to put in at least three years of cover cropping before they see results in their soil. “It’s not something that can be fixed overnight,” she said. “This is a long process.”

In the spring following the flood, DelCogliano spread various amendments on her least-damaged field, including compost, lime, biochar, and blood and bone meal, which provide nitrogen and phosphorus, respectively. After all that, she and her husband seeded crops.

Their new vegetables came in about two weeks later than normal, but the season was more productive than ever, even though they grew on just 4 instead of 6 acres—“which is pretty amazing,” she said. “When we first started harvesting crops [after Helene], we didn’t yet have power at the farm. I had to dig one of our sinks out of a bank and bleach it and clean it and drag it up to the new barn—that we barely got a roof on—to wash and pack for that first [farmers] market.”

She doesn’t really know what made the year so productive. They planted more intensively to account for the smaller acreage and were able to harness their years of expertise to restart their operation basically from scratch. She also attributes the relative health of her soil to years of organic practices. “We’re dirt farmers,” she said. “Our primary job is to tend the dirt. Because that’s the basis of everything.”

Some farmers who’ve seen good harvests may have gotten a little lucky. Rather than sand, floods dumped silt. Even Runion got silt deposits in one section of his farm. Unlike the sand, the silty layers carry nutrients and create a positive growing environment. “We have a producer we work with and he said it’s the most fertile soil that he’s had in decades,” said Emine Fidan, a biosystems engineering and soil science researcher at the University of Tennessee, who’s also working on Runion’s farm. “And he said it grew the sweetest corn he’s ever had. It was growing just beautifully.”


Runion didn’t plant anything until this past fall. He prepared about 65 acres of the 220 that were underwater. It was slow going; he used a disking machine to till his land but had to stop often to clear sticks and trash and to grade out low spots. He mixed in mulch and planted oats, wheat, and fescue. Walker drove me past one of the fields and it still looked sandy, the grasses just a pale green shadow on the tan land. Runion said the greenery was “struggling to have any vigor about it.” He won’t know for sure how well or poorly the grasses do until spring, their peak growing season.

He considered planting more acreage but decided to wait and see what he learned from Walker’s trials. “It’s a process, and the knowledge we’re gaining there will help on the whole rest of it, too,” Runion said.

This spring, Walker’s team will measure the biomass in each plot as well as the quality of the crop, including how much protein it has and its digestibility. They’ll also be evaluating the soil itself, including its ability to hold water, to determine if any of the treatments improved the structure of the sandy dirt.

One farmer thinks the hay he’ll get in the coming years will be lower-yielding, lower-quality, and will cost more to produce due to the extra prep time, new seeds, and fertilizers.

Preliminary results suggest that, in plots where they put down mulch, the grasses are growing better than in plots with other amendments. The woody debris is reducing erosion and seeds are germinating well and standing up in the rough matrix. Spreading this kind of mulch isn’t an obvious solution, Walker said: Wood chips are a carbon-rich material, but as they break down in the soil they consume nitrogen, which can lead to a deficiency for the crops. But this mulch had sat in piles and started to decompose before it was applied to Runion’s fields, which made it less likely to cause these problems.

Runion had asked FEMA to leave the piles of wood chips on his farm rather than remove them like they normally would. Walker is looking for solutions to the soil problem that not only work but are also accessible. Have a mountain of mulch? Put it to work. Have nearby chicken houses? Maybe their nitrogen-rich manure can help revive flooded fields. His hope is that his team’s research can provide some guidance to farmers who find themselves in similar situations in the future. “I think it will have broad implications for a number of different crops,” including vegetables, Walker said.

Meanwhile, Runion is coming to terms with his situation. He thinks the hay he’ll get in the coming years will be lower-yielding, lower-quality, and will cost more to produce due to the extra prep time, new seeds, and fertilizers. He used to sell a lot of square bales, which tend to contain high-quality grasses and fetch a higher price, but he doesn’t expect to be doing that for a while. He’d initially hoped to have his land back in shape in a year or two. “Now it’s a four- to five-year [plan], I think,” Runion said. “It has been frustrating, and exhausting, too.”

He’s still optimistic, though. On my visit, I watched him grade out the new campground in a large dump truck. Freshly exposed red soil lay open to the sky. He thinks he can get the campground open by late summer or early fall. Over time, he hopes, it will be a more lucrative, and more sustainable, source of income. “The farm is really beautiful,” Runion said. “It still has a lot to offer.”

—Irina Zhorov, Grist

This article originally appeared in Grist at https://grist.org/extreme-weather/hurricane-helene-ravaged-farmers-topsoil-theyre-still-fighting-to-build-it-back/.

Grist is a nonprofit, independent media organization dedicated to telling stories of climate solutions and a just future. Learn more at Grist.org

  • ✇Eos
  • 哪些国家因颗粒物空气污染付出的代价最大? Nathaniel Scharping
    Source: GeoHealth This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。 据世界卫生组织的数据,全球每年因空气污染导致的死亡人数估计达 700 万。其中大部分死亡病例是由PM2.5引起的,这种直径小于 2.5 微米的颗粒物能够进入肺部和血液,从而引发呼吸系统和心血管系统疾病。除了直接排放到大气中的颗粒物外,工厂、船只、汽车和发电厂排放的氨(NH3)、氮氧化物(NOX)和二氧化硫(SO2)等物质也是导致 PM2.5 形成的前体物。然而,颗粒物污染的影响并非均匀分布。 Oztaner等人对北半球各区域的空气污染后果进行了建模,从而更细致地分析了哪些地区的减排政策最为有效。他们利用美国环保署(EPA)社区多尺度空气质量(CMAQ)建模平台的多相伴随模型(multiphase adjoint model),从挽救生命和节省资金两个角度评估了减少各种污染物带来的效益。该研究通过国际机构所广泛采用的一种成熟方法,计算出了空气污染影响所造成的经济损失。不过,这种方法也引发了一些伦理方
     

哪些国家因颗粒物空气污染付出的代价最大?

16 April 2026 at 13:08
两座烟囱矗立在一片浓重的烟雾之中,而这些烟雾几乎完全遮蔽了城市的景色。
Source: GeoHealth

This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。

世界卫生组织的数据,全球每年因空气污染导致的死亡人数估计达 700 万。其中大部分死亡病例是由PM2.5引起的,这种直径小于 2.5 微米的颗粒物能够进入肺部和血液,从而引发呼吸系统和心血管系统疾病。除了直接排放到大气中的颗粒物外,工厂、船只、汽车和发电厂排放的氨(NH3)、氮氧化物(NOX)和二氧化硫(SO2)等物质也是导致 PM2.5 形成的前体物。然而,颗粒物污染的影响并非均匀分布。

Oztaner等人对北半球各区域的空气污染后果进行了建模,从而更细致地分析了哪些地区的减排政策最为有效。他们利用美国环保署(EPA)社区多尺度空气质量(CMAQ)建模平台的多相伴随模型(multiphase adjoint model),从挽救生命和节省资金两个角度评估了减少各种污染物带来的效益。该研究通过国际机构所广泛采用的一种成熟方法,计算出了空气污染影响所造成的经济损失。不过,这种方法也引发了一些伦理方面的担忧,因为它在评估生命价值时部分地依据了各国的人均国内生产总值(GDP)。

总体而言,研究发现,如果所有模型中的排放量减少 10%,那么在北半球每年将能挽救 513,700 人的生命,并节省 1.2 万亿美元的费用。

死亡率降幅最大的是中国和印度,削减排放量每年将分别挽救184,000人和124,000人的生命。成本节约幅度最大的也是中国,其次是欧洲和北美。健康效益也因排放类型和行业而异。氨(NH3)在中国造成的危害更大,而氮氧化物(NOx)在欧洲的危害相对高于其他地区。在整个北半球,农业部门是颗粒物和前体物污染的主要来源,预计农业相关排放量减少10%可挽救95,000人的生命,并节省约2900亿美元。其次是居民区和工业区。

作者指出,在对类似研究的结果进行比较时应保持谨慎,一部分原因是污染物浓度与健康结果之间的关联并非总是呈线性关系,还有一部分原因是不同地区在核算各行业排放量时可能采用不同的方法。此外,他们的研究仅关注与 PM2.5 相关的死亡率,未考虑如臭氧等其他污染物。总体而言,他们认为他们的研究为比较北半球不同污染物减排策略的效果提供了一个有意义的参考。(GeoHealth, https://doi.org/10.1029/2025GH001533, 2026)

—科学撰稿人Nathaniel Scharping (@nathanielscharp)

This translation was made by Wiley本文翻译由Wiley提供。

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  • Snail-Borne Diseases in Central Africa: Lessons from Citizen Science Muki Haklay
    Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Community Science Citizen science continues to spread across the world. It is becoming an acceptable and reliable practice to monitor and report on local conditions. Yet, it must adapt to local conditions and constraints – such as the profile of participants, their level of education, or the time that is available for them. So, how does citizen science adapt to Low- and Middle-Income Countries (LMIC)?
     

Snail-Borne Diseases in Central Africa: Lessons from Citizen Science

16 April 2026 at 12:00
Two pie charts from the study.
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: Community Science

Citizen science continues to spread across the world. It is becoming an acceptable and reliable practice to monitor and report on local conditions. Yet, it must adapt to local conditions and constraints – such as the profile of participants, their level of education, or the time that is available for them. So, how does citizen science adapt to Low- and Middle-Income Countries (LMIC)?

In Ashepet et al. [2026], we learn from the ATRAP (Action Towards Reducing snail-borne Parasitic diseases) project, which focuses on the monitoring of snail-borne disease in Uganda and the Democratic Republic of Congo (DRC). The researchers show how citizen science requires consideration such as material and social benefits for the participants, and how social structure and practices need to be taken into account. The paper also challenges the universality of the European Citizen Science Association (ECSA) 10 principles of citizen science

Citation: Ashepet, M. G., Mulmi, J., Michellier, C., Jacobs, L., Pype, K., & Huyse, T. (2026). Citizen science principles in practice: Lessons from Uganda and the democratic Republic of Congo. Community Science, 5, e2025CSJ000149. https://doi.org/10.1029/2025CSJ000149

—Muki Haklay, Editor, Community Science

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  • Cleanup of Battery Recycling Sites May Lower Childhood Lead Exposure Anuradha Varanasi
    Lead-acid batteries are omnipresent. An integral part of most electric vehicles and all conventional vehicles globally, they also serve as backup energy storage systems in developing countries. But if lead-acid batteries are recycled in smelting units without adequate pollution control measures, they can cause elevated lead pollution that persists in local soils for thousands of years. However, because recycling sites with pollution control measures cost millions of dollars, most efforts are in
     

Cleanup of Battery Recycling Sites May Lower Childhood Lead Exposure

15 April 2026 at 13:00
A person in an orange jumpsuit and a yellow hard hat takes a tool similar to a hoe to the dark soil they are standing on.

Lead-acid batteries are omnipresent. An integral part of most electric vehicles and all conventional vehicles globally, they also serve as backup energy storage systems in developing countries. But if lead-acid batteries are recycled in smelting units without adequate pollution control measures, they can cause elevated lead pollution that persists in local soils for thousands of years. However, because recycling sites with pollution control measures cost millions of dollars, most efforts are informal and unregulated.

In a recent study, researchers reported that scraping lead-contaminated soil in the vicinity of an abandoned recycling site for used lead-acid batteries and treating it with phosphate was linked to a 22% reduction in the blood lead levels (BLLs) of children who were living close to that site in a Bangladeshi town. The research was published in the International Journal of Hygiene and Environmental Health.

“Informal battery recycling is rampant in Bangladesh.”

“Informal battery recycling is rampant in Bangladesh,” said study coauthor Mahbubur Rahman, an environmental health scientist at the International Centre for Diarrhoeal Disease Research, Bangladesh. “Used lead-acid batteries are broken up and smelted in close proximity to residential and agricultural areas, which exposes those communities to lead emissions that contaminate their soil and water sources.”

Rahman and colleagues analyzed the BLLs of 130 children living close to two recycling sites for used lead-acid batteries (ULAB) in the Tangail District of Bangladesh that were abandoned in early 2019. They also assessed the BLLs of 37 children who did not live anywhere near ULAB recycling sites. The researchers then carried out soil remediation efforts at one of the ULAB sites but not the other. Prior to the work, the team members held informational sessions for the community about the dangers of lead pollution so locals could provide informed consent to participate.

The team observed that following remediation efforts, the lead content of the soil in and around the former battery recycling site decreased from more than 20,000 parts per million to less than 400 parts per million, which was considered acceptable by the U.S. EPA when the study was conducted, from 2022 to 2023. (The EPA reduced the limit to 200 parts per million in 2024.)

The researchers collected and cleaned up soil from children’s play areas, roadsides, and courtyards of 68 households that belonged to the intervention group. A year after the lead-contaminated soil was cleaned up, the 89 children from those households had the most significant decreases in their BLLs: from 90.1 to 70.4 micrograms per liter, a decrease of more than 21%.

“We know for sure that the areas close to abandoned ULAB recycling sites are as contaminated as areas around abandoned lead mines.”

The children in the group who lived close to the second abandoned ULAB recycling site, where soil remediation was not conducted, experienced only about an 8.4% decrease in their BLLs, from 88.5 to 81.1 micrograms per liter. The reduction in the control group’s BLLs could be attributed to a government initiative focused on reducing lead levels in turmeric, which was happening over the same time period as the study, Rahman said.

Anne Riederer, an environmental health scientist at the University of Washington who was not involved in the new study, said the dangers of lead exposure from ULAB recycling sites are well documented.

“We know for sure that the areas close to abandoned ULAB recycling sites are as contaminated as areas around abandoned lead mines. This study fits with the bigger picture of what we have learned to date about cleaning up contaminated sites and how that could improve children’s health,” she said.

A Widespread Issue

Similar studies conducted in Brazil and Bangladesh reported 46% and 35% reductions, respectively, in children’s BLLs following soil remediation initiatives around ULAB recycling sites.

Despite those drastic improvements, the children’s BLLs were still far above the World Health Organization’s threshold of 50 micrograms per liter. “This could mean there are other sources of lead exposure, like paints and cookware items,” said Rahman. “Or the persistently high BLLs could be because of chronic and long-term lead exposure, due to which lead gets deposited deep into the bones for several decades, even if [people] move away from toxic sites.”

Rahman explained that while soil remediation is an effective mitigation measure for lowering childhood lead exposure, it is also labor-intensive and expensive. Though the team identified hundreds of toxic sites borne from informal ULAB recycling, it wasn’t possible for them to remediate the soil at every site.

“The reason why this issue is so widespread is [that] informal recycling is cheap,” he said. “That makes the formal sector reluctant to invest in costly pollution control measures.”

—Anuradha Varanasi, Science Writer

Citation: Varanasi, A. (2026), Cleanup of battery recycling sites may lower childhood lead exposure, Eos, 107, https://doi.org/10.1029/2026EO260120. Published on 15 April 2026.
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  • Fixing Baltimore’s Unequal Weather Data Coverage Rebecca Owen
    Source: Community Science Heat, air pollution, and flooding can affect a city and the health of city residents. Yet few cities have a comprehensive network of weather stations providing accurate measurements of rainfall, humidity, and air temperature across different neighborhoods. Some of this information can be filled in by community members’ personal weather stations, like those connected through Weather Underground. But because of a lack of sensors and inconsistencies in data collection,
     

Fixing Baltimore’s Unequal Weather Data Coverage

13 April 2026 at 12:37
Six adults stand around a tripod that holds a personal weather station device. They are standing on grass, and several buildings are visible not far behind them.
Source: Community Science

Heat, air pollution, and flooding can affect a city and the health of city residents. Yet few cities have a comprehensive network of weather stations providing accurate measurements of rainfall, humidity, and air temperature across different neighborhoods. Some of this information can be filled in by community members’ personal weather stations, like those connected through Weather Underground. But because of a lack of sensors and inconsistencies in data collection, these types of community networks are often not reliable on their own. Furthermore, most personal weather stations are located in higher-income neighborhoods, with very few in lower-income, underserved neighborhoods.

The same is true in Baltimore, where personal weather stations are more prevalent in higher-income, majority-white neighborhoods around and stretching north from the Inner Harbor but are lacking in lower-income and majority-Black neighborhoods to the west and east. Furthermore, only one National Weather Service sensor is present in the city itself, in the Inner Harbor, and another sensor is located about 12 kilometers (8 miles) away at Baltimore/Washington International Airport.

Waugh et al. describe a partnership between universities, state agencies, and Baltimore residents to build the Baltimore Community Weather Network (BCWN) that addresses the missing data coverage around the city. Unlike the patchwork of personal weather stations, community members participating in the BCWN are from underserved areas in the city and are actively involved in data collection and interpretation.

Weather stations are placed in open spaces to avoid obstacles like buildings or trees affecting measurements of temperature, rainfall, or wind. This careful placement is designed to ensure that the data collected are as close as possible to the conditions experienced by actual residents.

BCWN sites are carefully monitored and managed by community members. Baltimore residents are actively involved in data collection, weather station management, and decisionmaking with scientists and local organizations to help promote engagement, education, and community empowerment.

Because Baltimore is not the only U.S. city that has historically lacked accurate weather data coverage, the BCWN system could be applied to other locations—or even used to monitor other environmental exposures, such as air pollution, the authors say. (Community Science, https://doi.org/10.1029/2025CSJ000154, 2026)

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

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Citation: Owen, R. (2026), Fixing Baltimore’s unequal weather data coverage, Eos, 107, https://doi.org/10.1029/2026EO260108. Published on 13 April 2026.
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