Feed aggregator

Modelers have demonstrated that artificial intelligence (AI) models can produce climate simulations with more efficiency than physics-based models. However, many AI models are trained on past climate data, making it difficult for them to predict how climate might respond to future changes, such as further increases in the concentration of greenhouse gases.

Predicting tropical cyclones (TCs) accurately is crucial for disaster mitigation and public safety. Although the forecasting accuracy of TC tracks has improved substantially in recent decades, progress in the forecasting of TC intensity remains limited. In recent years, deep learning methods have shown great potential in TC intensity prediction; however, they still face challenges, including limited interpretability, cumbersome feature engineering, and unreliable real-time operational forecasts.

In Hawaii, most of the population relies on private septic tanks or cesspools to dispose of sewage and other wastewater. There are more than 88,000 cesspools in the state, with about 55,000 on the Big Island alone. These systems, as opposed to more strictly regulated municipal wastewater treatment units, have a higher risk of sewage leaking into the porous substrate.

A recent study published in Frontiers in Marine Science identifies sewage-contaminated submarine groundwater discharge (SGD) sites, pinpointing specific locations that stakeholders may want to prioritize for mitigation efforts.

Modeling and Mapping

Previous studies estimated that groundwater flows deliver 3 to 4 times more discharge to oceans than rivers do, making them significant pathways for transporting pollutants.

In response to pollution concerns from the local community, a team from Arizona State University, with the support of the Hawaiʻi Marine Education and Research Center, used airborne mapping to identify locations where SGD reached the ocean along the western coastline of the Big Island.

Sewage-contaminated water (colored blue in this photograph) enters the ocean from submarine groundwater discharge sites on the Kona coast of the Big Island. Credit: ASU Global Airborne Observatory

To precisely identify these freshwater-seawater interfaces, researchers built on previous studies that used thermal sensors to capture the temperature difference between the two bodies of water. Figuring out which of these discrete interface points were problematic “was very challenging,” said Kelly Hondula, a researcher at the Center for Global Discovery and Conservation Science and first author of the study.

The team identified more than 1,000 discharge points and collected samples from 47 locations. “We chose points where we could localize freshwater emerging from the land or points of high community interest,” explained Hondula.

In addition to aerial surveys, researchers analyzed the discharge points by monitoring their salinity gradients and measuring levels of Enterococcus, a group of bacteria that frequently serve as key fecal indicators in public health testing. They integrated these data into a statistical model that used upstream land cover and known sewage sites to predict the likelihood of sewage and bacterial contamination for each SGD site along the western Hawaiʻi coastline.

The techniques allowed scientists to identify regions of the built environment that are associated with contamination. Besides areas with septic systems and cesspools, they found a high correlation between sewage discharge and development within the first 500 meters of the coast.

“Sewage going into the ground comes out in the ocean, with often a worrying level of waste contamination.”

The geology of a discharge point also contributes to its risk of contamination. Discharge points around the island’s South Kona region, for instance, feature “some of the youngest and most porous volcanic substrate in the archipelago, with little soil development and a high degree of hydrologic connectivity between point sources of pollution and coastal waters,” the authors wrote. Although South Kona has relatively sparse development, increased land use will likely have a disproportionate effect on groundwater quality, they concluded.

“We were surprised to find such clear results: Sewage going into the ground comes out in the ocean, with often a worrying level of waste contamination,” said Hondula.

Mapping Mitigation

As communities continue to invest in coastal development, understanding the effect of sewage discharge and how to avoid it is becoming an increasingly pressing concern worldwide.

As such, the new study “contributes to the growing body of evidence correlating sewage-tainted groundwater discharge with coastal water quality, showing a strong linkage between wastewater and development in the nearshore area. That’s something that land managers and conservation scientists should really take into account,” said Henrietta Dulai, a geochemist at the University of Hawaiʻi at Mānoa who was not involved in the study.

The state of Hawaii has recognized the particular risk posed by largely unregulated cesspools leaking sewage-contaminated groundwater to the ocean. In fact, there is a state mandate to eliminate cesspools by 2050, but the associated cost is slowing the process.

Many scientists say the costs of phasing out cesspools is far outweighed by the health benefits. “We need to consider the financial sides of replacing cesspools versus the benefit of preserving the water quality for the environment and the people,” said Tristan McKenzie, a researcher at the University of Gothenburg, Sweden, who was not involved in the study. “Studies like this highlight why we need to act now.”

—Anna Napolitano (@anna83nap; @anna83nap.bsky.social), Science Writer

Citation: Napolitano, A. (2025), Pinpointing sewage seeps in Hawaii, Eos, 106, https://doi.org/10.1029/2025EO250376. Published on 9 October 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: Journal of Geophysical Research: Machine Learning and Computation

Modelers have demonstrated that artificial intelligence (AI) models can produce climate simulations with more efficiency than physics-based models. However, many AI models are trained on past climate data, making it difficult for them to predict how climate might respond to future changes, such as further increases in the concentration of greenhouse gases.

Clark et al. have taken another step toward using AI to model complex Earth systems by coupling an AI model of the atmosphere (called the Ai2 Climate Emulator, or ACE) with a physical model of the ocean (called a slab ocean model, or SOM) to produce a model they call ACE2-SOM. They trained ACE2-SOM on output of a 100-kilometer-resolution physics-based model from a range of climates.

In response to increased atmospheric carbon dioxide, consistent with its target model, ACE2-SOM predicted well-known responses, such as surface temperature increasing more strongly over land than over ocean, and wet areas becoming wetter and dry areas becoming drier. When the researchers compared their results with those of a 400-kilometer-resolution version of the physics-based model they were emulating, they found that ACE2-SOM produced more accurate and cost-effective predictions: ACE2-SOM used 25 times less power while providing a resolution that was 4 times finer.

But ACE2-SOM struggled when the researchers asked it to predict what would happen if atmospheric carbon dioxide levels rose rapidly (suddenly quadrupling, e.g.). While the ocean surface temperature took the appropriate time to adjust, the atmosphere almost immediately shifted to the equilibrium climate under the new carbon dioxide concentration, even though physical laws would dictate a slower response.

To become fully competitive with physics-based models, AI climate models will need to become better able to model unusual situations, the authors write. The slab ocean model used in this study is also highly simplified. So to maintain their efficiency advantage while improving realism, AI models will also need to incorporate additional parts of the Earth system, such as ocean circulation and sea ice coverage, the researchers add. (Journal of Geophysical Research: Machine Learning and Computation, https://doi.org/10.1029/2024JH000575, 2025)

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

Citation: Sidik, S. M. (2025), A step toward AI modeling of the whole Earth system, Eos, 106, https://doi.org/10.1029/2025EO250362. Published on 9 October 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.

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

El Océano Austral existe en un estado de equilibrio precario. El mar está estratificado, con agua fría en la superficie y agua relativamente cálida debajo. Es una situación inherentemente inestable — en igualdad de condiciones, el agua cálida debería subir a la superficie. Pero es más salada y, por lo tanto, más densa, por lo que permanece en el fondo. La capa superior fría, en cambio, se mantiene más dulce con las nevadas y el hielo marino, que se forma cerca de la costa y luego se desplaza hacia el norte entrando al océano abierto antes de derretirse.

Durante los últimos diez años, la capa de hielo marino ha ido disminuyendo a medida que las temperaturas oceánicas se han calentado. El rápido deshielo ha aportado aún más agua dulce a la superficie, lo que debería reforzar la capacidad aislante de la capa de agua fría y permitir que el hielo marino vuelva a expandirse.

Sin embargo, ese ciclo de retroalimentación parece haberse interrumpido. Nuevos datos satelitales han revelado que el océano alrededor de la Antártida, contra todo pronóstico, se está volviendo más salado.

El estudio fue publicado en Proceedings of the National Academy of Sciences of the United States of America (PNAS).

Medir donde es difícil medir

El hielo marino, los mares agitados y la oscuridad permanente hacen que resulte prácticamente imposible monitorear la salinidad del Océano Austral desde un barco durante el invierno. Solo en años recientes ha sido posible medir la salinidad del océano Austral desde el espacio. Los satélites pueden observar la temperatura de brillo de la superficie oceánica, una medida de la radiación emitida en la superficie del océano. Cuanto más dulce es el agua, mayor es la temperatura de brillo.

La técnica funciona bien en aguas más cálidas, pero en aguas frías la temperatura de brillo no varía tanto como cambia la salinidad. Dado que estos cambios ya son, en general, bastante sutiles, los satélites no habían podido detectarlos con precisión en las regiones polares. En estas zonas, el hielo marino también tiende a nublar la señal.

Los avances recientes en tecnología satelital, sin embargo, han mejorado notablemente la sensibilidad de las lecturas de brillo, y los nuevos algoritmos permiten a los investigadores eliminar el ruido generado por el hielo marino.

El oceanógrafo Alessandro Silvano, de la Universidad de Southampton, y sus colegas analizaron los últimos 12 años de registros de salinidad del satélite de la Agencia Espacial Europea para la medición de la humedad del suelo y la salinidad oceánica (SMOS, por sus siglas en inglés). Para Alex Haumann, científico climático de la Universidad Ludwig-Maximilians de Múnich, Alemania, e integrante del equipo, contar con estos datos de amplio alcance — que cubren todo el Océano Austral con una resolución de 25 kilómetros cuadrados — representa un cambio revolucionario. “Debido a la gran cobertura y la serie temporal que puedes obtener, es super valioso. Es realmente una nueva herramienta para monitorear este sistema”, afirmó.

Con el calentamiento, esperamos que fluya más agua dulce hacia el océano. Por lo tanto, es bastante impactante que aparezca esta agua más salada en la superficie”

Sin embargo, cuando el equipo observó que la salinidad había aumentado durante ese periodo, no pudieron evitar cuestionar la tecnología. Para verificar lo que estaban observando, recurrieron a las boyas Argo, boyas automatizadas que toman muestras de agua a una profundidad de hasta 2000 metros. Una red de boyas flota en los mares del mundo, incluido el océano Austral.

Para sorpresa y consternación de Silvano, las boyas corroboraron los datos satelitales. “Muestran la misma señal”, dijo. “Pensamos, de acuerdo, esto es real. No es un error.”

Al comparar los datos sobre la salinidad con las tendencias del hielo marino, el equipo observó un patrón inquietante. “Existe una correlación muy alta entre la salinidad superficial y la capa de hielo marino”, explicó Haumann. “Cuando la salinidad es alta, el hielo marino es escaso. Cuando la salinidad es baja, hay más hielo marino.”

“Con el calentamiento, esperamos que fluya más agua dulce hacia el océano. Por lo tanto, es bastante sorprendente que aparezca esta agua más salada en la superficie”, afirmó Inga Smith, física especializada en hielo marino de la Universidad de Otago en Nueva Zelanda, que no participó en la investigación.

Un régimen cambiante

La explicación más plausible para el aumento de la salinidad, según Silvano, es que las delicadas capas de agua antártica se han alterado y el agua más cálida y salada que se encuentra debajo está ahora saliendo a la superficie, lo que hace que esta sea demasiado cálida para que se forme hielo marino.

Aunque subrayó que es demasiado pronto para determinar la causa de la surgencia, Silvano planteó que podría estar provocado por el fortalecimiento de los vientos del oeste alrededor de la Antártida, como consecuencia del cambio climático. Afirmó que teme que el mecanismo natural de control de daños de la Antártida, en el que el deshielo libera agua dulce, que a su vez atrapa el agua cálida de las profundidades y finalmente permite que se forme más hielo marino, se haya roto de forma irreversible.

El debilitamiento de la estratificación oceánica amenaza, en cambio, con crear una nueva y peligrosa retroalimentación en la que las potentes corrientes de convección traen aún más agua cálida y salada de las profundidades, lo que conduce a una pérdida descontrolada de hielo.

“Creemos que esto podría ser un cambio de régimen, un cambio en el sistema oceánico y glacial, en el que hay menos hielo de forma permanente”, señaló Silvano.

“Tenemos que encontrar formas de monitorear el sistema, porque está cambiando muy rápidamente”

Wolfgang Rack, glaciólogo de la Universidad de Canterbury en Nueva Zelanda, quien no participó en la investigación, dijo que el registro satelital aún no es lo suficientemente largo como para demostrar si el aumento en la salinidad es una anomalía o un nuevo estado normal, no obstante, añadió: “Es bastante improbable que se trate de una simple anomalía, porque la señal es muy significativa.”

Zhaomin Wang, oceanógrafo de la Universidad de Hohai en Nankín, China, que no participó en la investigación, afirmó que el estudio era un “resultado muy sólido,” pero advirtió que aún es demasiado pronto para atribuir de forma concluyente el retroceso del hielo marino a la surgencia. “Es bastante difícil desentrañar la causa y el efecto entre el cambio del hielo marino antártico y el cambio de la salinidad de la superficie”, dijo, “porque es un sistema acoplado, lo que dificulta determinar qué proceso inicia los cambios”.

Para Haumann, los hallazgos muestran lo crucial que es la nueva tecnología para rastrear los cambios en el océano Austral. “Tenemos que encontrar formas de monitorear el sistema, porque está cambiando muy rápidamente”, dijo. “Esta es una de las regiones más distantes de la Tierra, pero una de las más críticas para la sociedad. La mayor parte del exceso de calor que tenemos en el sistema climático va a parar a esta región, y esto nos ha ayudado a mantener el planeta a una tasa de calentamiento relativamente moderada”.

“Ahora no sabemos realmente qué va a pasar con eso», dijo.”

—Bill Morris, Escritor científico

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
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

An advanced filtration system inspired by nature that can recover untapped critical resources such as copper and lithium from mining waste is being developed by scientists from The Australian National University (ANU) in collaboration with Rio Tinto.

Author(s): Chinmoy Bhattacharjee

I investigate the formation of multiscale magnetic-field structures in a rotating, self-gravitating dusty plasma comprising electrons, ions, and charged dust grains. By incorporating the gravitomagnetic field, arising from mass currents in rotating astrophysical objects, into a three-component fluid…

[Phys. Rev. E 112, 045206] Published Thu Oct 09, 2025

Author(s): Johannes J. van de Wetering, Justin R. Angus, W. Farmer, V. Geyko, D. Ghosh, D. Grote, C. Weber, and G. Zimmerman

Anomalies observed in the neutron spectral shift of high-yield shots at the National Ignition Facility (NIF) suggest the presence of suprathermal ions [E. P. Hartouni et al., Nat. Phys. 19, 72 (2023)], implying that kinetic effects play a significant role in burning inertial confinement fusion (ICF…

[Phys. Rev. E 112, 045207] Published Thu Oct 09, 2025

Melting ice sheets in North America played a far greater role in driving global sea-level rise at the end of the last ice age than scientists had thought, according to a Tulane University-led study published in Nature Geoscience.

The tribunal has concluded that a major leak in a water main, which released 40 million liters of water, triggered the failure

On 14 January 2025, the McCrae landslide occurred on the Mornington Peninsula in Australia. The site is located at [-38.34631, 144.93500]. I posted about this event at the time, noting that local residents had observed large volumes of water bubbling out of the ground in the period leading up to the failure. The landslide caused property damage and it resulted in serious injuries to one person.

In the aftermath of the landslide, the Victorian Government established a formal Independent Board of Inquiry into the events – a rare response so a landslide of this type. That tribunal has now published its conclusions in a report that is available online. It contains 30 recommendations some of which are specific to this site, whilst others cover landslide management and response more generally. These have widespread application, and it is worth a read.

The Report includes this image of the aftermath of the McCrae landslide:-

The 14 January 2025 McCrae landslide. Image from the Board of Inquiry report.

The report is admirably definitive about the causes of the landslide. It notes that there were previous periods of movement on the slope, but that the events of 14 January 2025 started with movement that was observed on 5 January 2925. It states that:

“Water was the trigger of the 5 January 2025 landslide and the McCrae Landslide. The source of that water was the burst water main at Bayview Road.”

The Board of Inquiry has calculated that the burst water main released about 40 million litres of water. The leak started at least 150 days before the landslide occurred, and there were numerous reports made to the water authority that there were problems at the site. However, the leak was not detected and repaired.

As I noted above, some of the recommendations pertain to landslide management more generally. One (Recommendation 7) highlights the needs for proper protocols to respond to landslide incidents (this is a widespread problem). Others (Recommendations 18 and 21) highlight the need for better training and education with regard to landslides, whilst there is also a focus on a better understanding and identification of landslide risk (Recommendations 20 and 23), and clarity about responsibility for landslide management (Recommendations 29 and 30).

News reports in Australia indicate that the Victorian Government has accepted all the findings of the McCrae landslide inquiry. Plans are now in place to ensure that the issues at the site are addressed and that the householders who have suffered such heavy losses are treated appropriately.

Return to The Landslide Blog homepage Text © 2023. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

AbstractThe low-velocity layer confined by surrounding rocks deep in the subsurface acts as a seismic waveguide. The compressional (P-) and shear (S-) waves propagate in the waveguide are reflected on the top and bottom interface, constructively interfered with to formulate the deep-guided wave. Deep-guided wave has high-frequency contents and notable dispersive features. The dispersion represents the kinematics information and can be used to image the low-velocity structures. The Earth media not only shows elasticity but also attenuates seismic waves. This article presents a theoretical study of deep-guided wave propagation and dispersion analysis in viscoelastic media. We utilize the Thomson-Haskell propagator matrix method to theoretically calculate the phase velocity dispersion and attenuation curves of the deep-guided wave in viscoelastic media. We apply the staggered-grid finite-difference scheme to numerically simulate the elastic wavefield propagation in the shale layer for validation. We have conducted a sensitivity analysis of the dispersion and attenuation curves of the deep-guided wave with respect to different media parameters. The theoretical calculation of dispersion and attenuation curves of deep-guided wave opens the doors for the simultaneous inversion of S-wave velocity and quality factor of the low-velocity layer in the future. Deep-guided waves hold the potential for high-resolution imaging of hydrocarbon reservoirs, geothermal reservoirs, coal seams, saline aquifers, and fault zones.

Off the coast of Antarctica, the sea ice retreated toward the southernmost continent and, like a bottle cap taken off a soda bottle, that reduced pressure slowed down a process of critical carbon dioxide capture, dramatically accelerating the warming of the planet.

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.

Meteorologist and atmospheric scientist Neil Jacobs was confirmed as the new leader of NOAA on Tuesday evening.

Jacobs has a PhD in atmospheric science and worked in weather monitoring before joining NOAA in 2018.

But Jacobs is perhaps most well-known for his role in “Sharpiegate.” In 2019, during his first term, President Trump claimed that Alabama was in the path of Hurricane Dorian. After the claim met pushback, the president held a press conference and showed members of the media a map of the hurricane’s path that had been altered with a Sharpie, and NOAA issued a statement backing Trump’s claim.

President Trump displayed a map that altered the projected path of Hurricane Dorian with Sharpie. (The inked-in addition extends the white “Potential track area” and includes the Florida Panhandle, southern Georgia, and southeastern Alabama.) Credit: The White House

At the time, Jacobs was the acting NOAA administrator, and had approved the unsigned statement. A National Academy of Public Administration report later found that his involvement with the statement violated NOAA’s scientific integrity policy.

At Jacobs’ confirmation hearing in July, he said that, if a similar situation arose in the future, he would handle it differently. He also said he supported proposed cuts to NOAA’s budget, and that his top priorities included staffing the National Weather Service office, reducing the seafood trade deficit, and “return[ing] the United States to the world’s leader in global weather forecast modeling capability.”

 

Related

•   Roll Call Vote 119th Congress – 1st Session
 •  Senate Confirms ‘Sharpiegate’ Meteorologist to Lead NOAA
•  4 takeaways from Trump NOAA nominee’s confirmation hearing
•  US Weather Boss During ‘Sharpiegate’ Nears Return to a Shrinking Agency
 •  We Watched Neil Jacobs’ Confirmation Hearing for NOAA Administrator and Are Concerned About What We Heard
 •  Get Involved: AGU Science Policy Action Center

Jacobs made no mention of climate change in his opening statement. When asked whether he agreed that human activities are the dominant cause of observed warming over the last century, he noted “that natural signals are mixed in there” but that “human influence is certainly there” too.

The Senate voted 51-46 to confirm Jacobs, in a session during which they also confirmed a cluster of attorneys and ambassadors (including former NFL star Herschel Walker as ambassador to the Bahamas).

Carlos Martinez, a senior climate scientist at the Union of Concerned Scientists, expressed concern in a statement published before Jacobs’ confirmation hearing.

“Despite his relevant expertise and career experience, Dr. Jacobs has already demonstrated he’s willing to undermine science and his employees for political purposes as he did during the infamous ‘Sharpiegate’ scandal,” Martinez wrote.

Bluesky users reacted to the news. Credit: Michael Battalio @battalio.com via Bluesky‬

Others were more cautiously optimistic, noting his experience as a scientist. “It could be worse,” noted one Redditor. “He’s an actual atmospheric scientist and a known quantity.”

“I’m hopeful that he’s learned how to fight within the political system — because he is going to have to fight,” former NOAA administrator Rick Spinrad told Bloomberg in August.

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

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

Scientists can now receive near-real-time alerts about the world's lands as their surfaces change, thanks to a new satellite-based monitoring system described today in Nature Communications.

The Gulf of Mexico, a regional ocean, is hugged by the southeastern United States and a large stretch of the Mexican coast, making it very important for both countries. The area helps bring goods to local and global markets, produces power for the country with off-shore oil rigs, and hosts a myriad of vacation-worthy beaches—so modeling and predicting its dynamics is a critical task.

During recent storms, satellites recorded ocean waves averaging nearly 20 meters high—as tall as the Arc de Triomphe in Paris and the largest ever measured from space. Moreover, satellite data now reveal that ocean swells act as storm "messengers": even though a storm may never make landfall, its swell can travel vast distances and bring destructive energy to distant coastlines.

New research, based on forest fires in Australia, proves there is a significantly higher risk of large-scale flooding when major deforestation has occurred in catchment areas. The chance of large-scale flooding in a specific catchment area can increase by as much as 700% if widespread deforestation has occurred.

Across North America, abandoned oil and gas wells are leaking carbon dioxide and other greenhouse gases into the atmosphere. As of 2022, there were more than 123,000 documented orphaned wells in the United States, but researchers suspect the real number may be anywhere from 310,000 to 800,000.

Abandoned wells can be plugged by filling the drill holes with water or oil, but that process requires a substantial amount of liquid, as well as liquid assets. It would take 26 billion gallons—an amount that would fill almost 40,000 Olympic-size swimming pools—to plug 120,000 wells, with each well costing up to $1 million. (That’s $120 billion in total.)

“On the one hand, you have these underutilized waste products. On the other hand, you have abandoned oil wells that need to be plugged. It’s an abundant resource meeting an urgent demand.”

In a new study published in Energy Conversion and Management, researchers weighed the possibility of plugging wells and sequestering carbon with bio-oil made from vegetative waste. Their goal was to see whether the production of bio-oil could be a source of revenue for farmers while the oil itself could prevent greenhouse gases from escaping from abandoned wells.

“On the one hand, you have these underutilized waste products,” explained Mark Mba-Wright in a statement. Mba-Wright is a coauthor of the new paper, engineering professor at Iowa State University, and systems engineer at its Bioeconomy Institute. “On the other hand, you have abandoned oil wells that need to be plugged. It’s an abundant resource meeting an urgent demand.”

Biomass Bounty

The production of bio-oil starts with pyrolysis, the process in which vegetative waste decomposes under intense heat (≥1,000℉, or ~538°C°) in an oxygen-free environment. Pyrolysis produces three products: a liquid (bio-oil), a solid (biochar), and a gas. The gas is used to fuel future pyrolysis efforts, biochar can be sold as a soil amendment, and storing bio-oil underground has long been touted as an effective way to sequester carbon.

The fields and forests of the United States are ripe with plants and thus vegetative waste that could be used to produce bio-oil. For example, “for every kilogram of corn that the farmer produces, an additional kilogram of corn stover or biomass is produced,” said Mba-Wright.

Corn stover—the stalks, husks, and cobs left over after harvest—is a leading source of biomass for Midwestern farmers. In the western United States, woody forest debris is more widely available. To address this diversity of resources, Mba-Wright and his colleagues investigated the bio-oil potential of corn stover, switchgrass, pine, tulip poplar, hybrid poplar, and oriented strand board (an engineered product made with wood flakes and adhesives).

In partnership with Charm Industrial, a private carbon capture company, Mba-Wright and his colleagues sought to understand whether corn stover and other feedstocks would be suitable for bio-oil production, whether the process would be economically helpful to farmers, and whether the processing-to-plugging pathway would be effective at sequestering carbon.

Small-Scale Pyrolysis Feasibility

Charm has been using pyrolysis at a commercial scale for years, said Mba-Wright, but building large plants requires significant capital investment and risk.

Instead of a large, stationary plant, the team modeled the environmental and economic feasibility of an array of mobile pyrolysis units that could be located on farms. “You can imagine a farmer might be using his tractor or his combine on his field, and on the back of the unit have one of Charm’s pyrolysis units. And instead of letting the waste go to the field, it would be processed on site,” Mba-Wright explained.

In the modeled mobile pyrolysis scenario, the researchers found that the process could generate 5.3 tons of bio-oil and 2.5 tons of biochar for every 10 tons of corn stover. This estimate is slightly lower than the yield of bio-oil produced by other pyrolysis methods but is still reasonable.

The process of taking each feedstock from harvest to well plugging was carbon negative, the scientists found. Switchgrass had the highest carbon footprint at −0.62 kilogram of carbon dioxide (CO2) to kilogram of oil, and oriented strand board had the lowest carbon footprint at −1.55 kilograms of CO2 to kilogram of oil. Corn was in the middle, weighing in at −1.18 kilograms of CO2 to kilogram of oil.

An Array of Economics

Modeling indicated that the new pyrolysis process would be economically feasible as well, costing between $83.60 and $152 per ton of CO2. (The monetary difference accounts for the costs of including biochar sequestration.) These costs fall within the range of carbon credit commodity price ranges.

“The most important message is that there’s an economic case for carbon removal,” Mba-Wright said.

The scientists admit that to many individual farmers, however, this economic case might not seem like a bargain: The base capital cost of each pyrolysis unit would be $1.28 million.

“My impression was they were looking at this from the firm perspective, not exactly the farmer perspective,” said Sarah Sellars, an assistant professor of agricultural economics at South Dakota State University. “A base capital cost of 1.28 million? No farmer would invest in that. If they were going to spend $1.28 million, they’d probably buy more land.”

Mba-Wright said that although the costs are, indeed, significant, there are different options to consider. “Farmers could lease the equipment,” he suggested, adding that businesses could offer a lease-to-own option. “There are also intermediate solutions,” he added, “where you may have a unit that’s shared among farms.”

He acknowledged other challenges as well. Farmers “have a tight schedule during harvesting and planting. They may not want to have to operate another piece of equipment, so that’s something that suppliers of the unit will have to develop: a system that is easy for the farmer to use.”

Life Is Messy

On paper, sequestering carbon while halting fugitive emissions from orphan wells looks like a slam dunk.

But carbon and climate are complicated. “We can look at things from theory and economics and carbon mitigation, but then when it comes to these other variables, like the policy and the infrastructure to implement them, I think we should be cautious,” said Sellars. “Unfortunately, a lot of scientists don’t like to hear that, though. I mean, that’s why economics is called a dismal science.”

Lauren Gifford, director of the Soil Carbon Solutions Center at Colorado State University, agreed, adding that “a lot of what we’re reading in articles and things are promises or goals, but the industry just hasn’t taken off enough for us to see how these things play out at scale. A lot of what we see now is either hope or plans, and we know that real life is messy.”

—Sarah Derouin (@sarahderouin.com), Science Writer

Citation: Derouin, S. (2025), How might leftover corn stalks halt fugitive carbon?, Eos, 106, https://doi.org/10.1029/2025EO250378. Published on 8 October 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: Journal of Geophysical Research: Space Physics

In recent years, NASA’s Parker Solar Probe has given us a close-up look at the Sun. Among the probe’s revelations was the presence of numerous kinks, or “switchbacks,” in magnetic field lines in the Sun’s outer atmosphere. These switchbacks are thought to form when solar magnetic field lines that point in opposite directions break and then snap together, or “reconnect,” in a new arrangement, leaving telltale zigzag kinks in the reconfigured lines.

McDougall and Argall now report observations of a switchback-shaped structure in Earth’s magnetic field, suggesting that switchbacks can also form near planets.

The researchers discovered the switchback while analyzing data from NASA’s Magnetospheric Multiscale mission, which uses four Earth-orbiting satellites to study Earth’s magnetic field. They detected a twisting disturbance in the outer part of Earth’s magnetosphere—the bubble of space surrounding our planet where a cocktail of charged particles known as plasma is pushed and pulled along Earth’s magnetic field lines.

Closer analysis of the disturbance revealed that it consisted of plasma both from inside Earth’s magnetic field and from the Sun. The Sun constantly emits plasma, known as the solar wind, at supersonic speeds in all directions. Most of the solar wind headed toward Earth deflects around our magnetosphere, but a small amount penetrates and mixes with the plasma already within the magnetosphere.

This illustration captures the signature zigzag shape of a solar switchback. Credit: NASA Goddard Space Flight Center/Conceptual Image Lab/Adriana Manrique Gutierrez

The researchers observed that the mixed-plasma structure briefly rotated and then rebounded back to its initial orientation, leaving a zigzag shape that closely resembled the switchbacks seen near the Sun. They concluded that this switchback most likely formed when magnetic field lines carried by the solar wind underwent magnetic reconnection with part of Earth’s magnetic field.

The findings suggest that switchbacks can occur not only close to the Sun, but also where the solar wind collides with a planetary magnetic field. This could have key implications for space weather, as the mixing of solar wind plasma with plasma already present in Earth’s magnetosphere can trigger potentially harmful geomagnetic storms and aurorae.

The study also raises the possibility of getting to know switchbacks better by studying them close to home, without sending probes into the Sun’s corona. (Journal of Geophysical Research: Space Physics, https://doi.org/10.1029/2025JA034180, 2025)

—Sarah Stanley, Science Writer

Citation: Stanley, S. (2025), Magnetic “switchback” detected near Earth for first time, Eos, 106, https://doi.org/10.1029/2025EO250374. Published on 8 October 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.

Author(s): Magnus F. Ivarsen, Jean-Pierre St-Maurice, Glenn C. Hussey, Kathryn McWilliams, Yaqi Jin, Devin R. Huyghebaert, Yukinaga Miyashita, and David Sibeck

During the 23 April 2023 geospace storm, we observed chorus-wave-driven, energetic particle precipitation on closed magnetic field lines in the dayside magnetosphere. Simultaneously and in the ionosphere's bottom side, we observed signatures of impact ionization and strong enhancements in the ionosp…

[Phys. Rev. E 112, 045203] Published Wed Oct 08, 2025