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Come on Feel the Noise: Machine Learning for Seismic-Wind Mapping on Mars

Tue, 04/01/2025 - 12:00
Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Journal of Geophysical Research: Planets

Despite providing critical insights into atmospheric dynamics and weather patterns, wind observations on the surface of Mars remain relatively rare. The Temperature and Wind for InSight (TWINS) instrument onboard NASA’s Insight mission was designed to measure wind speed and direction winds. However, due to power constraints caused by increasing dust accumulation on InSight’s solar panels, TWINS primarily operated during the first 750 Martian days (sols) of the mission. In contrast, the Seismic Experiment for Interior Structure (SEIS) instrument operated almost continuously until the mission’s final transmission on Martian day 1440.

Since winds are the dominant source of energy in the seismic data, Stott et al. [2025] developed a machine learning model, WindSightNet, to map seismic data to wind speed and direction, nearly doubling the coverage of TWINS. The authors find an overall good agreement between both datasets during the first 750 sols, increasing confidence in WindSightNet data for the remaining Martian Days. Using this validated dataset, the authors analyze the interannual (one year on Mars is 669 sols) variability of wind speed and direction, as well as large-scale weather patterns and the height of the lower atmosphere throughout the Insight mission.

This dataset delivers a precious long-term and continuous record of Martian winds for the atmospheric community to refine their atmospheric models and better understand how dust is lifted on Mars. While the approach by the authors cannot capture the fastest wind variations or highest wind speeds recorded by TWINS due to a lower sampling rate, nor accurately predict wind speeds near 0 meters per second due to SEIS’s noise level, this study opens new possibilities for planetary instrumentation.

Citation : Stott, A. E., Garcia, R. F., Murdoch, N., Mimoun, D., Drilleau, M., Newman, C., et al. (2025). WindSightNet: The inter-annual variability of martian winds retrieved from InSight’s seismic data with machine learning. Journal of Geophysical Research: Planets, 130, e2024JE008695. https://doi.org/10.1029/2024JE008695   

—Germán Martínez, Associate Editor; and Beatriz Sánchez-Cano, Editor, JGR: Planets

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

An Earth System Science Approach to Geophysics

Tue, 04/01/2025 - 12:00
Editors’ Vox is a blog from AGU’s Publications Department.

Geophysics is a powerful tool for understanding how our planet works. It enables us to connect complex real-world phenomena with fundamental physical laws, deduce the nature of otherwise inaccessible regions of the Earth, frame natural processes and events in terms of cause and effect, and mathematically model and predict the future behavior of components of the Earth.

Earth System geophysics recognizes the critical importance of interactions between the components of the Earth System—the solid earth, oceans, atmosphere, and even the biosphere—in achieving that understanding. An Earth System perspective also recognizes convection as a universal process and a unifying theme for studying the Earth.

A new book in AGU’s Advanced Textbook Series, Earth System Geophysics, helps upper-level students learn how to apply math and physics to understand the operation of the Earth System. Here, we asked the book’s author to explain how an Earth Systems approach bolsters the study of geophysics and how to make these topics engaging and accessible to students.

Why take an Earth Systems approach to studying geophysics?

There was a time when geophysics was mainly devoted to the study of the ‘solid earth’—the crust we stand on and the mantle and core below. With that focus, it made sense to treat plate tectonics as the unifying theme. But why limit our view to the solid earth? The oceans and atmosphere also behave geophysically and are ultimately driven by the same kind of process—convection—behind plate tectonics. Furthermore, studying the solid earth alone would be incomplete if interactions with the rest of the Earth System were ignored.

Idealized conception of mantle convection, including descending lithospheric slabs, upwelling plumes, and broad background flow. These components of mantle convection can interact with the core, oceans, atmosphere, and biosphere in different ways. Credit: Jellinek and Manga [2004], Figure 17

How did you come up with the idea for the Earth System Geophysics textbook?

When I first started teaching at SUNY-Binghamton, I was given free rein to teach the ‘rest’ of geophysics, in other words, anything non-seismological. My research has always been ‘global’—involving the various ways Earth’s rotation can be affected by plate motions, ocean tides, and the oceans’ response to atmospheric pressure variations—so it seemed natural to take a global approach in teaching. And, that global approach apparently increased students’ interest (even to the point where they didn’t mind complex math being introduced)! However, I could find no existing geophysics textbook with an Earth System Science approach at the level I wanted to teach this material.

How is the textbook organized?

The textbook comprises two parts: (I) An Earth System Science Framework and (II) A Planet Driven by Convection. The first part includes chapters on Earth’s origin, the evolution of its atmosphere, and the climate system. The second part covers gravity, seismology, heat flow, and geomagnetism, with frequent application to the Earth System.

How could instructors use this textbook in their teaching, and who is the intended audience?

The textbook is fairly lengthy—an unavoidable consequence of trying to explain how the Earth works! Instructors using the entire book to teach about geophysics in the Earth System should plan on a two-semester course. However, as outlined in the textbook’s preface, combinations of different portions of the book can serve as the basis for a variety of one-semester courses, including traditional solid-earth geophysics, climate change, and seminar classes exploring geophysical research.

This book’s primary audience is geology students at the senior undergraduate or beginning graduate level, whose exposure to basic physical geology has been supplemented by at least one semester each of calculus and college physics but who may be somewhat unconfident about using math and physics to understand the Earth. Undergraduate and graduate students majoring in geophysics, physics, and engineering, as well as students working toward a master’s in Earth science teaching, can benefit from this textbook too.

How does your textbook make geophysics accessible to students?

Geophysics is intrinsically a mathematically intensive field, and—on several levels—many students find that daunting. My textbook introduces mathematical concepts gently and builds gradually; where possible, qualitative interpretations are also presented. 

For example, the concept of gradient is first discussed qualitatively in early chapters. Then, it is expressed mathematically using simple calculus. The relevant mathematical and qualitative concepts build throughout the book, until (in the final two chapters) students are able to fully appreciate and employ the gradient as a three-dimensional vector.

What special features appear in your textbook?

Perhaps my most notable feature is the use of ‘stop and think’ questions—moments where I pause the narrative and directly address the reader, in effect encouraging the reader to connect the subject being discussed with previous material (or, sometimes, to anticipate impending material). Additionally, I use specific formatting to highlight definitions of essential terms, explanations of key concepts, and important formulas and equations. Also, a companion website includes homework exercises for each chapter and brief guidance for instructors on the mathematical level of each chapter.

Another feature I’m very proud of is the extensive reference list and abundant in-text citations. In an era when the honesty and validity of science are repeatedly questioned, those citations emphasize that science is not just a story created out of thin air to make some conclusion believable; it is a synthesis of independent results obtained by a great number of peer-reviewed researchers.

Finally, numerous color figures throughout enhance what is already interesting subject matter.

Earth System Geophysics, 2024. ISBN: 978-1-119-62797-5. List price: $169.95 (hardcover), $136 (e-book).

The preface is freely available. Visit the book’s page on Wiley.com and click on “Read an Excerpt” below the cover image.

Editor’s Note: It is the policy of AGU Publications to invite the authors or editors of newly published books to write a summary for Eos Editors’ Vox.

—Steven R. Dickman (dickman@binghamton.edu, 0000-0001-5909-453X), Binghamton University, United States

Citation: Dickman, S. R. (2025), An Earth System Science approach to geophysics, Eos, 106, https://doi.org/10.1029/2025EO255013. Published on 1 April 2025. This article does not represent the opinion of AGU, Eos, or any of its affiliates. It is solely the opinion of the author(s). Text © 2024. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

The July 2024 landslide cluster in Zixing County, Hunan Province, China

Tue, 04/01/2025 - 06:27

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

Back in February I highlighted a Sixth Tone article about the extraordinary landslide cluster that was triggered by Typhoon Gaemi in Hunan Province in China between 26 and 28 July 2024. A paper (Zhao et al. 2025) has now been published in the journal Landslides that provides a more detailed documentation of the event.

As a reminder, this is a Planet satellite image of the aftermath of Typhoon Gaemi in Zixing County, the worst affected area:-

A part of the area of Zixing in Hunan Province after being impacted by the July 2024 rainstorm. Image copyright Planet, used with permission, collected on 5 August 2024.

Zhao et al. (2025) have recorded 19,764 landslides from this single event, an extraordinary number. It is worth looking in a little more detail at the density of landslides in this area. The marker in the centre of this image is located at [23.13507, 95.78573]:-

A part of the area of Zixing in Hunan Province after being impacted by the July 2024 rainstorm. Image copyright Planet, used with permission, collected on 20 March 2025.

Zhao et al. (2025) note that 128,000 people were affected, with 1,714 houses being destroyed and 65 people killed.

A key issue in an event such as this is the rainfall conditions that can cause such an impact. During Typhoon Gaemi, Zixing County averaged 412.7 mm of rainfall, but one weather station recorded 673.9 mm. The maximum 24 hour rainfall was 642.5 mm; the previous record 24 hour rainfall in Hunan Province was 365.4 mm. Thus, this event broke the record to an extraordinary degree. In a landscape with many slopes, multiple landslides were inevitable. I would however be very interested in the peak hourly rainfall, which is likely to have been a key factor, if this data is available.

The failures were mostly small, shallow landslides. The landslide rate was higher in areas in which there had been excavation of the slope for roads or houses.

These types of intense landslide clusters are not in any way unprecedented, but the number of events globally in 2024 was unusually high. This is driven by extreme rainfall associated with the exceptionally high atmospheric temperatures last year.

It is a sign of what is to come in the years ahead.

Reference

Zhao, J., Feng, W., Yi, X. et al. 2025. Clustered shallow landslides caused by extreme typhoon rainstorms in Zixing County, Hunan Province, China, from July 26 to 28, 2024Landslides. https://doi.org/10.1007/s10346-025-02508-9

Planet Team. 2025. Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https://www.planet.com/

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.

Climate Scientists Unite to Nominate U.S. Experts for IPCC Report

Mon, 03/31/2025 - 15:39
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.

In late February, delegates from more than 190 countries met in Hangzhou, China to make preliminary decisions about the timing and content of the seventh assessment report from the Intergovernmental Panel on Climate Change (IPCC). The Trump administration barred U.S. delegates from attending the February meeting, one step among many the president has taken to abandon America’s global leadership on climate change.

The IPCC is a United Nations body that reviews the science behind climate change. Since 1990, the group has produced assessment reports that evaluate the latest developments in climate science, impacts, adaptation, and mitigation. The reports also assess whether counties are doing enough to combat the climate crisis (spoiler: not nearly enough) and play an important role in influencing climate policy around the world. Those reports depend on the contributions of scientific experts nominated by IPCC member countries and Observer Organizations.

 
Resources

To supplement nominations by the federal government, the U.S. Academic Alliance for the IPCC (USAA-IPCC) is facilitating nominations to the seventh assessment cycle for the IPCC. The alliance is a network of U.S. universities that are registered observers with the IPCC and is hosted by AGU, which publishes Eos. U.S. researchers can submit materials to self-nominate as experts, authors, and review editors for the next IPCC assessment report.

“This new alliance will help the U.S. maintain a preeminent position in global science-policy assessments,” Pamela McElwee, professor of human ecology at Rutgers University and chair of the USAA-IPCC steering committee, said in a statement. “The benefits to U.S. researchers from involvement in the IPCC are tremendous, and we want to ensure that our scientists continue to play an important leadership role internationally.”

Nominations are open through Friday, 4 April. U.S.-based experts in climate research or practice who are U.S. citizens are eligible. Learn more about the nomination process here and at the video below:

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

Correction 1 April 2025: An earlier version of this article mistakenly listed AGU as an IPCC Official Observer and has been edited to clarify.

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. Text © 2024. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

DOGE and GSA Target Mine Safety Office for Cuts

Mon, 03/31/2025 - 15:34
body {background-color: #D2D1D5;} Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today.

The Mine Safety and Health Administration (MSHA), which works to protect U.S. miners from injury, illness, and death on the job, is among the latest federal agencies targeted for cuts by the Department of Government Efficiency (DOGE).

In collaboration with the General Services Administration, or GSA, DOGE has begun terminating leases for hundreds of offices and buildings for groups such as NOAA, the Natural Resources Conservation Service, geological surveys in several states, and the National Park Service. According to coverage by the Pittsburgh Post-Gazette, Grist, and others, the list includes at least 34 centers run by MSHA, which conduct regular inspections of quarries and mines to ensure worker safety.

It is unclear whether the lease terminations will involve layoffs or relocating workers to other MSHA office locations.

Related

When MSHA first began operation under the Mine Act of 1977, 242 U.S. miners died in mining accidents. In 2025, there were 31, according to the MSHA website.

Federal regulators at MSHA also created a rule, set to take effect in April, which cuts in half the amount of silica allowed in air, in an effort to reduce a new form of black lung disease.

Wayne Palmer, tapped by President Trump to be the next leader of MSHA and who held the position during Trump’s first term, recently served as an executive at the Essential Minerals Association, which filed a legal brief challenging the new rule.

In a statement provided to several news outlets, a GSA spokesperson said: “A component of our space consolidation plan will be the termination of many soft term leases. To the extent these terminations affect public facing facilities and/or existing tenants, we are working with our agency partners to secure suitable alternative space.”

In a statement, United Mine Workers of America International President Cecil E. Roberts said the organization was “troubled” by the news. To keep workers safe, she added, both unions representing workers’ best interests and government agencies enforcing laws are necessary.

In their absence, “workers’ safety will be left solely in the hands of employers. History has shown us time and time again that doing so is a recipe for disaster, especially in the mining industry.”

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

Cinturones polvorientos ofrecen una visión más clara de la formación de exoplanetas

Mon, 03/31/2025 - 13:38

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

Los cinturones polvorientos de escombros provenientes del nacimiento de estrellas son extensos y dinámicos, alimentados por colisiones frecuentes entre exocometas y agitados por la gravedad de planetas cercanos, según un estudio reciente publicado en Astronomy & Astrophysics. Los hallazgos ofrecen nuevas perspectivas sobre el proceso de formación planetaria.

Estos cinturones son análogos al Cinturón de Kuiper del sistema solar, una zona con forma de rosquilla más allá de la órbita de Neptuno que alberga cientos de millones de cuerpos helados. Los cinturones de exocometas analizados en el nuevo estudio presentan una amplia variedad de características, incluyendo diferencias en anchura, masa y brillo. Según los autores, estos cinturones probablemente fueron esculpidos por exoplanetas aún no detectados.

“Lo que encuentro más emocionante es que este estudio demuestra, una vez más, que los planetas están en todas partes. Incluso si no podemos verlos directamente, detectamos sus huellas en estos discos”.

“Encontramos que cada cinturón es único, por lo que cada sistema planetario es diferente”, dijo el miembro del estudio, Steve Ertel, un astrónomo del Observatorio Steward y científico principal del Observatorio del Gran Telescopio Binocular, ambos en la Universidad de Arizona. “Pero lo que encuentro más emocionante es que este estudio demuestra, una vez más, que los planetas están en todas partes. Incluso si no podemos verlos directamente, detectamos sus huellas en estos discos.”

Investigadores del proyecto REASONS (Observaciones resueltas de ALMA y SMA de estrellas cercanas) produjeron imágenes de alta resolución de los sistemas de cinturones alrededor de 74 estrellas situadas a aproximadamente 500 años luz de la Tierra, constituyendo la muestra más grande hasta la fecha.

El equipo realizó nuevas observaciones de algunos de estos sistemas utilizando el Gran Conjunto Milimétrico/submilimétrico de Atacama (ALMA) en Chile y el Conjunto submilimétrico (SMA) en Hawái, los cuales son instrumentos sensibles al resplandor del polvo y los pequeños guijarros que conforman los cinturones. Los investigadores combinaron estos resultados con observaciones previas de otros sistemas realizadas con ALMA para completar el conjunto de muestras.

Los investigadores utilizaron el Atacama Large Millimeter/submillimeter Array (ALMA) en Chile (en la imagen), junto con el Submillimeter Array (SMA) en Hawái, para observar los cinturones de exocometas. Crédito: ESO/B. Tafreshi (twanight.org) Fragmentación de exocometas

Los cinturones se encuentran a distancias de entre 10 y 100 unidades astronómicas (1 UA equivale a la distancia promedio de la Tierra al Sol) de sus estrellas centrales, una escala comparable a las 30 UA que separan al Sol del borde interno del Cinturón de Kuiper. Estos cinturones se forman a partir de objetos de hasta aproximadamente 1 kilómetro de diámetro, similares a los cuerpos del Cinturón de Kuiper y a los cometas que ocasionalmente visitan el sistema solar interior, razón por la cual se les denomina “exocometas”.

Dichos cuerpos podrían ser restos de los bloques a partir de los cualesnacieron planetas y lunas. En el caso del Cinturón de Kuiper, muchos fueron lanzados lejos del Sol por la gravedad de esos planetas recién formados.

“En las regiones donde observamos estos anillos fríos, se cree que los cuerpos están compuestos por grandes cantidades de hielo, además de material rocoso o polvo”, explicó Ertel. “Cuando estos cuerpos colisionan, se fragmentan en piezas cada vez más pequeñas, y eso es lo que observamos como polvo”.

Este polvo proporciona “perspectivas importantes sobre los sistemas planetarios subyacentes”, señaló Ertel, ya que, al igual que en el Cinturón de Kuiper y el cinturón de asteroides de nuestro propio sistema solar, las propiedades de estos cinturones están estrechamente relacionadas con las órbitas y masas de los planetas.

Los cinturones de exocometas estudiados por REASONS pueden parecerse al Cinturón de Kuiper de nuestro propio sistema solar, como se muestra en este concepto artístico. Crédito: ESO/M. Kornmesser

Algunos sistemas presentan más de un anillo o banda, sugiriendo la posible presencia de múltiples planetas, mientras que el grosor de ciertos anillos indica que podrían contener cuerpos con diámetros de entre aproximadamente 140 kilómetros y el tamaño de la Luna (cuyo diámetro es de unos 3,500 kilómetros). Aunque estos cuerpos son demasiado pequeños para ser detectados en las observaciones de REASONS, su influencia en la dinámica interna de los anillos es significativa.

“La principal sorpresa probablemente fue el hecho de que los cinturones anchos parecen ser más comunes que los anillos estrechos”, mencionó Luca Matrà, físico del Trinity College de Dublín y autor principal del estudio. “Muchos de nosotros apreciamos la imagen del hermoso anillo de Fomalhaut, probablemente el cinturón de exocometas más famoso. Sin embargo, nos sorprendió mucho descubrir que estos anillos son raros”.

Según Matrà, varios factores pueden influir en la forma y el tamaño de los anillos, incluidos los choques entre objetos dentro de los cinturones, las condiciones iniciales en las que se formaron y las interacciones entre el material de los cinturones y los planetas cercanos, posiblemente como resultado de migraciones planetarias.

Las condiciones iniciales incluyen la cantidad de material disponible para formar los cinturones, la luminosidad de la estrella y el entorno estelar circundante. Una estrella más brillante y caliente debería evaporar hielos a mayores distancias dentro del disco de material a partir del cual se forman los bloques de construcción planetarios, conocidos como planetesimales. Una mayor cantidad de material en el disco primordial podría dispersarse más y protegerse mejor de la radiación estelar, evitando la pérdida de polvo hacia el espacio interestelar. En contraste, si una estrella se formó en un cúmulo compacto, las interacciones con otras estrellas podrían haber limitado el crecimiento de los discos formadores de planetas.

Provocando un poco de entusiasmo

Las migraciones planetarias, en las que las interacciones gravitacionales hacen que los planetas se desplacen hacia o lejos de su estrella, podrían provocar que los objetos se agiten en anillos estrechos, los cuales son comunes en sistemas estelares jóvenes donde se están formando nuevos planetas, como pedacitos de hielo en una licuadora. Este movimiento de agitación podría hacer que los anillos se expandan hasta formar los cinturones más anchos que se observan en la actualidad.

“Hubo mucha actividad en el sistema solar temprano, y ahora estamos viendo que ocurren cosas similares en otros lugares. Me parece realmente fascinante”.

“En nuestro propio sistema solar, es probable que Urano y Neptuno no estuvieran originalmente tan lejos del Sol como lo están hoy, sino que fueron empujados hacia el exterior por Júpiter y Saturno”, explicó Sharon Montgomery, profesora de física en la Pennsylvania Western University en Clarion, quien no participó en el nuevo estudio. “Eventualmente, Neptuno provocó todo tipo de agitaciones en el Cinturón de Kuiper. Así que hubo mucha actividad en el sistema solar temprano, y ahora estamos viendo que ocurren procesos similares en otros lugares. Me parece realmente fascinante”.

El nuevo estudio también indica que las estructuras de polvo pierden tanto masa como superficie a medida que envejecen, y que los anillos y cinturones más pequeños se desgastan más rápidamente que los más amplios. Según los investigadores, ambos hallazgos concuerdan con los modelos de formación planetaria y evolución de discos.

Matrà señaló que el equipo ampliará su investigación mediante un estudio más detallado de algunos de los objetivos del proyecto REASONS. “Tomamos 18 de estos cinturones y llevamos al límite la resolución de ALMA, utilizando la máxima resolución posible para abordar nuevas preguntas cruciales”, afirmó Matrà. Las respuestas deberían proporcionar una comprensión aún más profunda de estas intrigantes bandas de exocometas.

—Damond Benningfield, Escritor de ciencia

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

Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Thriving Antarctic Ecosystem Revealed by a Departing Iceberg

Mon, 03/31/2025 - 13:37

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

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

“We immediately decided to go there and see [what] the seafloor looks like under the ice.”

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

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

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

Luck and Daring

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

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

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

As creatures of interest are spotted on video screens, Maritza Castro of Chile’s Universidad Católica del Norte and other researchers react with excitement in the remotely operated vehicle mission control room on board R/V Falkor (too). Credit: Alex Ingle/Schmidt Ocean Institute, CC BY-NC-SA 4.0

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

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

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

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

“Good luck played a huge role. We cannot deny that. But there’s also value in daring to explore the unexplored.”

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

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

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

Thriving Beneath the Ice

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

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

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

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

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

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

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

A Future Without Ice

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

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

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

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

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

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

Citation: Cartier, K. M. S. (2025), Thriving Antarctic ecosystem revealed by a departing iceberg, Eos, 106, https://doi.org/10.1029/2025EO250124. Published on 31 March 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Remagnetization Illuminates Tectonic Consolidation of Megacontinents

Mon, 03/31/2025 - 12:00
Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Journal of Geophysical Research: Solid Earth

During the late Ediacaran period (about 550–540 million years ago), Earth experienced significant biological, geochemical, and geomagnetic changes, leading to widespread remagnetization particularly in the carbonate rocks of West Gondwanaland.

Pescarini et al. [2025] present detailed paleomagnetic records focusing on remanence carriers to better constrain remagnetization mechanisms. These records were obtained from deeper drill core samples and fully oriented outcrop samples adjacent to the International Continental Drilling Program boreholes, part of the “Geological Research through Integrated Neoproterozoic Drilling: The Ediacaran-Cambrian Transition” project.

Magnetic mineralogy and paleomagnetic data revealed two magnetic components. C1 is a recent viscous remanent magnetization used to reorient the drill core samples, while C2 is a stable, large-scale remagnetization component carried by very small pyrrhotite (Fe7S8) and magnetite (Fe3O4). The remagnetization mechanism is best explained by thermoviscous and thermal remanent magnetization, indicating prolonged heating above 300°C during the tectonic consolidation (collision and subsequent cooling) of the West Gondwanaland megacontinent. The quasi-synchronous remagnetization across the Gondwana craton around 490-480 million years ago challenges the earlier fluid percolation hypothesis, as it cannot account for the tightly clustered remagnetization poles and the predominance of a single reverse polarity.

Citation: Pescarini, T., Trindade, R. I. F., Evans, D. A. D., Kirschvink, J. L., Pierce, J., & Fernandes, H. A. (2025). Magnetic mineralogy and paleomagnetic record of the Nama Group, Namibia: Implications for the large-scale remagnetization of West Gondwanaland and its tectonic evolution. Journal of Geophysical Research: Solid Earth, 130, e2024JB030612. https://doi.org/10.1029/2024JB030612

—Agnes Kontny, Associate Editor, JGR: Solid Earth

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

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