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SummaryThe reliable classification of seismic events is crucial to precise seismic cataloging and robust hazard evaluation. Recent advances in deep learning have achieved great success in seismic event identification, leveraging their exceptional ability to automatically extract and recognize features. However, existing deep learning approaches to seismic classification rely exclusively on deterministic models, which cannot quantify epistemic uncertainty, preventing the estimation of prediction confidence that is critical for reliability evaluation. To address this issue, in this paper, we develop two uncertainty-aware deep learning models for earthquake (EQ) vs. explosion (EP) classification using the DiTing 2.0 artificial intelligence training dataset: a Bayesian convolutional neural network (BCNN) and a dropout-based CNN (DropCNN). We also implement a conventional deterministic CNN as a baseline model for comparative analysis. The experimental results demonstrate that both the BCNN and DropCNN can achieve a classification accuracy comparable to the conventional CNN, while providing additional uncertainty metrics for estimation confidence of prediction. Crucially, their uncertainty scores increase markedly in terms of encountering misclassifications or out-of-distribution samples compared to correct classifications, enabling automatic rejection of unreliable predictions based on the uncertainty threshold setting, triggering human verification or alternative discrimination methods. We then apply the trained models to analyze suspicious explosion events in the DiTing 2.0 dataset. The BCNN and DropCNN results exhibits strong agreement, consistently identifying 79 EP and two EQ events and flagging the remaining samples as uncertain classifications needing further verification. Our findings demonstrate that deep learning methods incorporating uncertainty estimation not only maintain a high accuracy in seismic event discrimination but also provide uncertainty estimation. This capability significantly enhances the model’s reliability and decision-making value in practical applications.

SummaryThe central portion of the 2019 ± 2 Ma Vredefort (South Africa) impact structure comprises a 40-50 km diameter central uplift of Archean basement rocks surrounded by a 15-20 km wide collar of late Archaean to early Proterozoic Witwatersrand Supergroup sedimentary and volcanic rocks. The collar is characterized by a ring of strongly negative (←5 500 nT) aeromagnetic anomalies surrounding much of the structure where the strata dip steeply to overturned. To better understand the origin of this magnetic feature, we undertook a ground survey along 20 transects (340 km) in the Vredefort structure using a three-axis fluxgate magnetometer mounted on a mountain bicycle. Upward continuation of our profiles to 150 m matches the aeromagnetic data in shape and amplitude. From the bicycle measurements, we pinpointed the rocks responsible for the extremely negative anomalies. Field observations and microfabric analyses of the rocks from six outcrops substantiated that the magnetic signal correlates with 10-100 m thick metamorphosed banded iron formations (BIFs) at the base of the supergroup as the main producer of the anomalies. Paleomagnetic samples collected from the rocks at the surface that produce the most intense anomalies (up to -22 000 nT) have extremely high natural remanent magnetization intensities (up to > 1000 A·m−1) likely arising from lightning strikes. Stepwise demagnetization and rock magnetic experiments establish a new protocol to distinguish samples that escaped remagnetization from lightning and possess the established 2.02 Ga paleodirection at Vredefort. From a suite of thermoremanent magnetization (TRM) experiments, the best estimate for the paleofield intensity at the time of impact was 52 μT, corresponding to an average remanence of 32.5 A·m−1. The results of the TRM experiments together with the paleodirection enabled us to successfully model the prominent negative anomalies in the metasediments only when accounting for the post-impact orientation of the BIFs. We interpret the strongly negative magnetic anomalies in the collar region as being formed directly after crater exhumation and uplift of the rocks. This interpretation implies that Bushveld-related metamorphism at 2.06 Ga created the up to mm-sized magnetite and garnet crystals in the BIFs, which resided at temperatures higher than the Curie temperature of magnetite (580°C) until the impact rapidly brought the BIFs close to the surface, where magnetite cooled to acquire a thermal remanence in the 2.02 Ga field.

SummaryMagnetic fabric analysis of dikes is a powerful technique when assessing magma transfer processes. This study presents an integrated analysis combining magnetic susceptibility and anisotropy of magnetic susceptibility (AMS), magnetic mineralogy, geochemistry, and new ⁴⁰Ar/³⁹Ar dating of dikes intruding formations ranging from the Lower Cretaceous to the Miocene on the island of Maio, in the Cabo Verde archipelago. We show that the dikes, dated at ≈ 9.2 Ma, intruding the younger Miocene Casas Velhas formation, display a Ti-rich titanomagnetite composition, higher whole-rock TiO2 content and very high magnetic anisotropy. They are clearly distinguished from the dikes, ranging in age from ≈ 9.3 to 11.3 Ma, intruding older formations, which show a predominantly Ti-poor titanomagnetite composition with multiple magnetic phases, lower whole-rock TiO2 concentration, higher range of magnetic susceptibilities and very low anisotropy. Magnetic fabric is predominantly normal with no significant imbrication relative to the dike margins. Numerical analysis of fabric shows a dominant coaxiality between the magnetic lineation and the preferred orientation of opaques and phenocrystals suggesting that magnetic lineation is, therefore, the proxy of the magmatic flow axis orientation. Based on the orientation of the magnetic fabric, we infer that magmatic flow within the studied dikes is predominantly vertical. The differences observed between the younger dikes and all other dikes may be related to magma sourced from distinct magma chambers. One, probably shallow, underneath the Casas Velhas fm in the southwest of the island, which would explain the very high values of magnetic anisotropy and the inferred vertical flow, and another located in a central position in the island, responsible for the dikes intruding the older formations. The location of such magma reservoirs and the dikes ages suggest a hypothetical migration with age of the magmatic sources that fed the dikes from the central part of the island to the southwest region. The magnetic and mineralogical heterogeneities of the dikes intruding older Lower Cretaceous formations may also be a result of a wider age range of the intrusions.

SummaryIn Distributed Acoustic Sensing (DAS), a fiber-optic cable is used as a distributed seismic sensor, with channels representing successive short sections of the fiber, spaced at defined intervals along the 1D fiber axis. Typically, the positions of these channels are assumed to be a line projection along the cable's position. In reality, a fiber-optic cable contains many fibers that are not perfectly straight and are thus longer than the cable itself. Consequently, the real channel positions may not correspond to a simple interpolation along the cable axis. Moreover, the precise cable coordinates are often sensitive information and may not be provided to the end user who uses the cable for sensing applications. On land, a tap test is usually carried out before the start of a DAS acquisition to determine the exact channel locations. DAS with marine horizontal cables has recently been used for various offshore applications, including seismic imaging. To avoid errors in the seismic image, a precise receiver location is required. In this paper, we propose a traveltime-based inversion workflow to determine a more accurate channel position on the seafloor. Moreover, we show that we can resolve an unknown time shift between the acquisition and the recording system, in addition to the fiber position.

Experts are calling for a global effort to identify "positive tipping points" to accelerate the green transition—and have devised a method to find them.

А.П. Черняев

Обзор посвящён физическим основам ядерных технологий в медицине. Отмечены физические идеи, использованные при создании высокотехнологичных медицинских приборов и систем, а также ключевые моменты развития "ядерной медицины". Прослеживается история появления таких систем в России и мире, потребности здравоохранения, обсуждаются современные тенденции их развития. Описана система подготовки соответствующих кадров.

As Greenland's ice retreats, it's fueling tiny ocean organisms. To test why, scientists turned to a computer model from JPL and MIT that's been called a laboratory in itself.

Climate change warps the timing of natural processes. Scientists have evidence that flowers are blooming, trees are dropping their leaves, and animals are emerging from hibernation earlier than they did years prior.

“We’re seeing a trend towards an earlier onset.”

Now, there’s new evidence of another climate-related shift: California’s wildfire seasons are beginning as much as 46 days earlier than the typical onset 3 decades ago. The analysis, published in a paper in Science Advances, found that the trend was similar in almost all of California’s varied ecosystems.

The study defined wildfire season onset as the day when 5% of that season’s fires have occurred. “We’re seeing a trend towards an earlier onset,” said Gavin D. Madakumbura, a hydroclimatologist at the University of California, Los Angeles and lead author of the new study. “We wanted to understand what’s causing this.”

Previous work, including one landmark 2006 study, indicated that in some western U.S. forests, the wildfire season has both lengthened and started earlier.

To quantify the role of climate change in those trends, Madakumbura and his colleagues first analyzed U.S. Forest Service fire occurrence data and season start dates from 1992 to 2020 in California’s 13 ecoregions, from mountains in the north to deserts in the south. They found that since 1992, fire season has started earlier in all but one ecoregion (the Sonoran Basin and Range). The Cascades ecoregion shifted the most, with its 2020 onset occurring 46 days earlier than in 1992.

“The fact that they can see [the shift] across a broad array of ecosystems, most of them statistically significant, is noteworthy,” said LeRoy Westerling, a climate scientist at the University of California, Merced who was the lead author of the 2006 study that first indicated the shift. Westerling was not involved in the new study.

Though the shift in onset timing has been suspected for years, its magnitude is “much larger” than anticipated and “truly surprising,” wrote Virginia Iglesias, a climate scientist at the University of Colorado Boulder who was not involved in the new study, in an email.

Northern California ecoregions showed stronger trends than southern ecoregions, with the Eastern Cascades, Cascades, Central California Foothills, and Coastal Mountains showing the most significant changes. Madakumbura said the north-south difference exists because northern ecoregions’ fire seasons are more sensitive to changes in winter snowpack, which has also dwindled as the climate warms.

Climate Change’s Role

The team then evaluated the role of climate change as a driver of each ecoregion’s fire season start dates.

For each ecoregion, they determined how strongly climate-related drivers, such as how dry fuels were, influenced fire season start date compared with drivers that were not directly related to climate change, such as vegetation type. Then they compared changes observed for each of those drivers through time.

“The calendar-based boundaries we’ve long relied on for fire preparedness may no longer hold.”

The result suggested that although natural variability and severe droughts in the mid-2010s contributed to earlier fire seasons, climate change was a major driver of the earlier season in 11 of the 13 ecoregions.

“The climate, and the aridity of fuel, is the main controlling factor,” Madakumbura said.

“The paper presents compelling evidence that anthropogenic climate change is a dominant and quantifiable driver of the earlier wildfire season onset,” Iglesias wrote. “The logic is clear and the conclusions are well supported.”

As the climate continues to warm, fire seasons in California will likely start even earlier, the authors wrote. Knowing that fire seasons are trending earlier can help emergency managers prepare for longer fire seasons that burn more area, Madakumbura said.

“An earlier start to the season just taxes all these resources that much earlier,” Westerling said. “It’s the same people, the same equipment, and the same budgets that are under stress.” Fire season in California is extending later into the fall as well, he said, creating a much longer period when communities need to stay prepared for fires.

The asymmetry between northern and southern trends “highlights the need for regionally tailored fire management and climate adaptation strategies,” Iglesias wrote.

“The calendar-based boundaries we’ve long relied on for fire preparedness may no longer hold.”

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

Citation: van Deelen, G. (2025), California’s getting an earlier start to wildfire season, Eos, 106, https://doi.org/10.1029/2025EO250297. Published on 6 August 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.

Analysis of ocean sediments has surfaced geochemical clues in line with the possibility that an encounter with a disintegrating comet 12,800 years ago in the Northern Hemisphere triggered rapid cooling of Earth's air and ocean. Christopher Moore of the University of South Carolina, U.S., and colleagues present these findings in the journal PLOS One on August 6, 2025.

Researchers are calling for a more reliable approach to understanding water-related hazards by explicitly accounting for uncertainty in their predictions, arguing this could improve how communities prepare for the risk of floods, droughts, and river-related erosion.

When an enormous 8.8 magnitude earthquake struck near Russia's Kamchatka Peninsula, the impact reached far beyond its epicenter. In the passing hours, tsunami alerts were issued by several nations with coastlines along the Pacific Ocean's Ring of Fire, prompting evacuations and escalating emergency response efforts from Japan to Hawaii and along the U.S. West Coast. Due to a number of geological factors, this disaster did not result in significant damage or loss of life. That said, it served as a powerful reminder that in the face of rapidly moving natural hazards, the primary defense is time, and the systems that give us a chance to act before time runs out.

A recent study in Nature Geoscience offers important new insights into the hidden role of ancient groundwater beneath the ocean floor—and how it may have interacted with ice sheets and rising sea levels during past climate changes.

Source: Global Biogeochemical Cycles

Human activity is shifting the type of nitrogen flowing out of Arctic rivers and into the Arctic Ocean, a new publication shows. The amount of organic nitrogen, which is derived from living things, is going up. Meanwhile, the amount of inorganic nitrogen, which is produced from nitrogen in the air through chemical reactions, is going down.

Ruyle et al. sampled water from sites at six Arctic rivers: the Kolyma, Lena, Ob, and Yenisey in Russia; the Mackenzie in Canada; and the Yukon in the United States. Together, these watersheds cover about two thirds of the land area that drains into the Arctic Ocean. From 2003 to 2023, researchers collected samples from the rivers five to six times per year and measured the abundance of various forms of nitrogen. In four of the six rivers (Lena, Ob, Yenisey, Mackenzie), the ratio of dissolved organic nitrogen to total nitrogen (i.e., the sum of organic and inorganic nitrogen) increased significantly during that period at a rate between 1% and 2% per year.

The team applied newly developed models to these measurements to identify environmental and climate conditions associated with changes in nitrogen composition. The amount of water flowing through rivers, the extent to which surrounding permafrost has thawed, and the prevalence of burned landscape are all key drivers of the shift from inorganic to organic nitrogen, they found. Climate change is intensifying all of these conditions, so the trend is likely to continue.

Photosynthetic organisms such as algae and cyanobacteria typically use inorganic nitrogen to fuel their growth, whereas organisms that eat other living things can use organic nitrogen. The microbes that cause harmful algae blooms are typically photosynthetic.

So in the coming years, a decrease in inorganic nitrogen in these rivers could lead to fewer harmful blooms in coastal regions where river inputs are most important. However, the overall effects of a shift from inorganic to organic nitrogen are not completely understood, and the authors suggest the shifts should be the subject of future research. (Global Biogeochemical Cycles, https://doi.org/10.1029/2025GB008639, 2025)

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

Citation: Sidik, S. M. (2025), Arctic rivers trade inorganic nitrogen for organic, Eos, 106, https://doi.org/10.1029/2025EO250292. Published on 6 August 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.

Smelting metals and burning coal vaporize small amounts of iron. Some of this iron wafts out of East Asia and into the North Pacific Ocean, where it supercharges phytoplankton growth, a new study found.

The study, published in the Proceedings of the National Academy of Sciences of the United States of America, used isotope analysis to estimate that around 39% of the iron in seawater sampled from the North Pacific during the springs of 2016, 2017, and 2019 came from human activities. This added iron is helping phytoplankton consume marine nitrogen faster, causing a long-term northward shift in a North Pacific algal bloom.

“The nitrogen is like a paycheck that they get every year, and when they have more iron, they spend through it faster.”

“The nitrogen is like a paycheck that they get every year, and when they have more iron, they spend through it faster,” said the study’s first author, Nick Hawco, a marine geochemist at the University of Hawaiʻi at Mānoa.

Strong winds churn the waters of the North Pacific every winter, lifting nitrogen and other nutrients to the surface. As ocean currents carry the nutrients south toward a region of mixing gyres called the North Pacific Transition Zone, they fuel a phytoplankton bloom that extends from California to Japan. Tuna, humpback whales, and other sea creatures come to feast on the animals supported by the phytoplankton.

Over the spring and summer, the phytoplankton exhaust the nutrients brought south by currents. This depletion causes the southern extent of the bloom, called the transition zone chlorophyll front, to shift north each year, toward the nutrient-rich subarctic.

Have Iron, Will Travel

Hawco and his colleagues studied the metabolisms of phytoplankton captured from the North Pacific and found signs of iron deficiency. Iron is a limiting factor for phytoplankton growth in the region, the authors argued.

Though desert dust carried long distances by winds historically brought iron to the North Pacific, previous research has shown that industrial activities in East Asia—especially burning coal and melting metals—are a new and growing source of iron.

Between 1998 and 2022, steel production in China, Japan, South Korea, and Taiwan quadrupled, and coal use more than tripled, according to data from the Global Carbon Project and the World Steel Association. During the same period, the southern edge of the bloom in April shifted north by about 325 miles (520 kilometers), according to satellite measurements of chlorophyll.

“This extra iron is leading to the nitrogen being drawn down earlier in the season, and it’s pushing these waters that eventually become nitrogen limited further to the north.”

In the northern parts of the phytoplankton bloom, chlorophyll concentrations increased, suggesting that the added iron is driving a more intense bloom, according to the authors. As a consequence, the southern edge of the bloom does not reach as far south during the spring, Hawco said. The nutrients that used to fuel it are likely being consumed by the more intense bloom up north, he said.

“This extra iron is leading to the nitrogen being drawn down earlier in the season, and it’s pushing these waters that eventually become nitrogen limited further to the north,” said Peter Sedwick, a chemical oceanographer at Old Dominion University in Virginia who was not involved in the study.

Northward movement of the bloom could have wide-ranging effects. Because the ecosystem supports abundant marine life, many anglers from Hawaii travel there to fish, Hawco said. As it shifts north, that trip is becoming longer and more expensive, he said.

Chlorophyll concentrations, a proxy for phytoplankton, shift seasonally. Credit: NASA Earth Observatory

In addition, research suggests that climate change will reduce the amount of nutrients brought from the depths to the surface of the North Pacific. That will reduce the supply of nutrients brought south by currents, causing the southern extent of the bloom to move even farther north, Hawco and his colleagues said. Iron emissions and climate change are having synergistic effects on the transition zone chlorophyll front, they concluded.

Further research is needed to understand the impacts of this extra metal. The phytoplankton bloom sucks up carbon and helps maintain the balance of carbon dioxide between the ocean and the atmosphere, Sedwick said. Any change to the ecosystem could alter that balance, he added.

—Mark DeGraff (@markr4nger.bsky.social), Science Writer

Citation: DeGraff, M. (2025), Iron emissions are shifting a North Pacific plankton bloom, Eos, 106, https://doi.org/10.1029/2025EO250286. Published on 6 August 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: Biogeosciences

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

当地震引起滑坡、泥石流或侵蚀时，它可以通过引入颗粒更大的沉积物来改变附近湖泊的组成，导致沉积物堆积更快，并影响碳封存。堆积在湖底的沉积物就像一个历史档案，记录了湖泊的生物、物理和化学变化，以及它们如何影响硅藻（微小的玻璃状藻类）等微生物。然而，人们对于地震引发的突然扰动会如何影响湖泊生态系统知之甚少。

Xue等人观察了喜马拉雅地区措普湖（Lake Tsopu）的长期变化。1900年至2017年期间，措普湖周围200公里半径内发生了63次5级以上地震。这里的高海拔、高寒气候和低人类活动使得措普湖成为研究这些地震引起的微生物和地球化学变化的理想场所。

2017年，研究人员从措普湖中心水深14米处采集了一个45厘米长的沉积物岩芯。然后，他们将岩芯分成41个1厘米长的样本进行分析。研究人员发现了1900年至1923年间发生的两次大地震（7.09级和7级）的标志。一个标志是深度为28到35厘米处的砂粒含量增加，另一个标志是，与较浅处（1到23厘米）相比，深度较深处（28到35厘米）的颗粒大小中位数增加。

研究人员按照两个时间段对沉积物岩芯进行划分，第一阶段包含地震事件（1886-1917），第二阶段包括地震后的几十年（1923-2017）。他们注意到，地震后硅藻数量急剧减少，这可能是因为沉积物和氮的增加。在第一阶段，硅藻的多样性暂时增加，而后在第二阶段减少，这可能是由于沉积物的横向运输。此外，底栖物种在地震后减少，而漂浮物种则激增。

根据措普湖的研究结果，研究人员估计，全球大约有15000个湖泊——约占全球湖泊数的1.1%和湖泊面积的1.7%——在大地震之后经历了类似的剧烈变化，改变了水面以下以及周围景观的生态系统平衡。(Journal of Geophysical Research: Biogeosciences, https://doi.org/10.1029/2024JG008723, 2025)

—科学撰稿人Rebecca Owen (@beccapox.bsky.social)

Read this article on WeChat. 在微信上阅读本文。

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

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

Editors’ Vox is a blog from AGU’s Publications Department.

Some may think writing or editing a scholarly book is something scientists only do later in their careers after several decades of research, teaching, and other professional experience. On the contrary, two scientists who completed book projects with AGU as early-career researchers found the years right after earning their PhD to be the ideal time to pursue this opportunity. In the first installment of three career-focused articles, these scientists reflect on the positive outcomes the experience had on their professional development.

Matthew Currell co-edited the book Threats to Springs in a Changing World: Science and Policies for Protection, which explores the causes of spring degradation and strategies to safeguard them. Rebekah Esmaili authored Earth Observation Using Python: A Practical Programming Guide, a book on basic Python programming to create visualizations from satellite data sets. We asked Currell and Esmaili about why they chose to complete book projects as early-career researchers, the unique strengths early-career researchers bring to such endeavors, and the impacts their books had on their careers.

How would you describe the early-career researcher stage in a scientist’s career?

MC: The first decade of a researcher’s career is a time of great discovery, when the world opens up in front of you. This period can also have its challenges and be quite daunting. It is when responsibility to identify the big research questions of our time, design quality research projects, and start supervising other researchers in training is handed to you all at once. Staying true to the motivations and passion that led you into research in the first place—and making sure you take time to keep listening and learning from those with experience, insight, and knowledge in your field—are key to success. 

Even though early-career contributions differ from those of senior researchers, they are still incredibly important for the community to continue thriving.

RE: Early-career researchers are the fresh growth on the knowledge tree, branching out in new directions. They have novel ideas and the enthusiasm to share them, and are quick to learn and adopt new concepts and technologies, so they help the tree gather nutrients and grow. It’s an exciting time to work alongside senior researchers who are astoundingly knowledgeable. A challenge is that early-career researchers may struggle to find their voice; but even though early-career contributions differ from those of senior researchers, they are still incredibly important for the community to continue thriving.

Why did you decide to write or edit a book?

RE: I did not plan on writing a book until I presented a scientific workshop, “Python for Earth Observation,” at an AGU annual meeting. I was inspired to simultaneously teach Python skills while showcasing the visually stunning, publicly available imagery produced by Earth satellites. I initially planned to offer the workshop only once, but the participants’ feedback showed strong interest in the material. Since then, I have presented the workshop every year that I could attend AGU. I decided to write the book to amplify my workshops and to make the content accessible to those unable to travel to conferences. Writing a book appealed to me because books can be widely shared and referenced, and can provide greater detail than is possible during a 4-hour workshop.

MC: The idea for the book first came in an email from my co-editor on the project, Dr. Brian Katz. As soon as I saw the suggested topic on freshwater springs, I was hooked and quickly became determined to make the book a reality. Having spent time with many people, including Aboriginal Traditional Owners from my home country, Australia, I knew how important springs are as a source of water but also a source of life, culture, and connection to the land. I also knew firsthand how many springs were under threat, and how urgent the task was of promoting good science and good policy in the way we manage these springs.

What impact did your book have on your career?

The biggest value and benefit from the book was all the fantastic people and relationships that it helped to build.

MC: I think the biggest value and benefit from the book was all the fantastic people and relationships that it helped to build. For example, the chapter on springs in the Great Artesian Basin at Kati Thanda was very well received by the Arabana Rangers, who are the custodians of the springs and the lands of northern South Australia. This relationship has grown, and now the Arabana Rangers are set to come and present their story of the springs at the upcoming International Association of Hydrogeologists Congress, where I’m organizing the program through the conference technical committee. 

RE: Writing a book was a huge project, but doing so helped me master the subject matter, as I had to think deeply about the content and consider how digestible it would be to a new programmer. It also gave me the confidence to take on challenges at work. For example, learning to break down tasks into smaller pieces during the publication process empowered me to apply for larger grants and projects. Project management at work felt less overwhelming because after writing a book, I had experience writing proposals, developing milestones, creating reasonable schedules, collaborating with multiple partners, and delegating chapter reviews.

What were the benefits of completing a book as an early-career researcher, as opposed to doing so at another point in your career? 

RE: Early-career scientists can have more empathy for the reader because they have more recent experiences learning new concepts built upon knowledge they have not mastered yet. My awareness of the audience was a strength, and I ended up writing the book I wished I had when I was getting started. I was sensitive to using dense, discipline-specific language that was challenging to understand. Instead, I made a conscious choice to use clear, kind, and encouraging language. If I had written the book later in my career, it might have resembled a traditional textbook, many of which make assumptions about what the reader should already know.

MC: The book helped me to get in touch with many fantastic people around the world working in freshwater springs research, and I had the chance to learn a huge amount from editing the different chapters that present case studies from around the world. These relationships have inspired new ideas and collaborations, and the circle keeps growing —for example, through the global network of researchers called “the Fellowship of the Spring.” Finally, completing a book and seeing it published also brought a huge sense of accomplishment.

—Matthew Currell (m.currell@griffith.edu.au, 0000-0003-0210-800X), Griffith University, Australia; and Rebekah Esmaili (rebekah.esmaili@gmail.com, 0000-0002-3575-8597), Atmospheric Scientist, United States

This post is the first in a set of three. Stay tuned for posts about leading a book project in the mid-career stage and as an experienced researcher.

Citation: Currell, M., and R. Esmaili (2025), Early-career book publishing: growing roots as scholars, Eos, 106, https://doi.org/10.1029/2025EO255025. Published on 6 August 2025. This article does not represent the opinion of AGU, Eos, or any of its affiliates. It is solely the opinion of the author(s). Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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

Boulders are ubiquitous on the lunar surface. However, the lifetime of boulders on the surface is relatively short, lasting no longer than a few hundred million years, as the boulders are broken down and eroded in the space environment. Therefore, the presence of rocks indicates relatively recent activity. The rock abundance and size distribution can provide information on the evolution of the lunar surface and the development of the dust and rock fragments that comprise the regolith.

Rock abundance maps have been generated in the past by fitting models to thermal data. However, the rock abundance derived from the images provides greater detail about the size distribution of the rocks and their locations. Manually identifying and measuring the sizes of boulders on the lunar surface using images from orbiting spacecraft is very time consuming and laborious. As a result, a global map of boulders identified from images requires automated methods.

Aussel et al. [2025] use a deep learning algorithm to identify and measure the size of approximately 94 million boulders, providing the first near-global map of boulders larger than 4.5 meters across the lunar surface between 60° S and 60° N. The data show boulders are concentrated around impact craters and steep slopes. Distinct differences occur between the maria and highlands, with maria having higher densities of boulders, but with smaller average sizes. However, a significant variation in abundances is observed on different mare units suggesting differences in the properties of the volcanic rocks. The study also quantifies the size distribution of boulders and how the largest boulder sizes ejected by impact craters scale with crater size. While this study finds general agreement with the thermally derived maps, local differences are observed likely due to the sensitivity of the techniques to different rock sizes and geologic settings.

The study highlights how cutting-edge machine learning techniques can push the boundaries of what can be done in planetary science and can open up new avenues in research that previously were intractable. The end result is a rich dataset that has the potential to yield continued insights into the lunar environment, and the processes that shape that environment, as the research community studies the data further.  

Citation: Aussel, B., Rüsch, O., Gundlach, B., Bickel, V. T., Kruk, S., & Sefton-Nash, E. (2025). Global lunar boulder map from LRO NAC optical images using deep learning: Implications for regolith and protolith. Journal of Geophysical Research: Planets, 130, e2025JE008981. https://doi.org/10.1029/2025JE008981

—Jean-Pierre Williams, Editor, JGR: Planets

Text © 2025. The authors. CC BY-NC-ND 3.0
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Author(s): Iván Calvo, José Luis Velasco, Per Helander, and Félix I. Parra

Until now, quasi-isodynamic magnetic fields have been the only known stellarator configurations that, at low collisionality, give small radial neoclassical transport and zero bootstrap current for arbitrary plasma profiles, the latter facilitating control of the magnetic configuration. The recently …

[Phys. Rev. E 112, L023201] Published Wed Aug 06, 2025

A possible cause of the 5 August 2025 landslide is the failure of a large body of glacial material high in the valley above the village.

The imagery that is emerging after the 5 August 2025 debris flow in Dharali (Tharali), in Uttarakhand, northern India make very somber viewing. Melaine Le Roy posted this comparison to BlueSky, which illustrates the scale of the flow that has struck the village:-

BEFORE/AFTER the Dharali village debris flow today!

SummaryTransform faults are one of the major tectonic plate boundaries offsetting the global mid-oceanic ridge system. The topographic features within these transform faults provide crucial evidence for tectono-magmatic processes and crustal accretion in transform fault zones. These interesting features include median ridges, which are major bathymetric anomalies found within both slow-slipping and fast-slipping transform faults, often associated with exposures of ultramafic rocks on the seafloor. To explain the origin of median ridges, previous studies have invoked multiple processes such as serpentinite diapirism, thermal uplift at ridge-transform intersections, or transpressive uplift induced by global plate reorganization, without any knowledge of the seismic structure. Here, we present results from 2D travel time tomography of downward-continued multi-channel seismic data along and across an ∼80 km long median ridge that lies within the eastern end of the slow-slipping (∼3.4 cm/yr) Chain transform fault in the equatorial Atlantic Ocean. The data were acquired during the 2018 ILAB-SPARC survey using a 6-km long streamer. Our high-resolution P-wave velocity model of the median ridge shows distinct high and low velocities ranging from 2.5 to 5 km/s within 500 m below the seafloor, on either side of the presently active strike-slip fault trace that cuts through the ridge. The low velocity on the eastern side of the ridge could be due to the presence of highly fractured basalt (with porosity in the range of 28 to 36 per cent) due to transform fault motion, whereas the high velocity on the western flank could be due to the presence of gabbro or highly serpentinised peridotite. The basaltic origin of the median ridge is supported by the observation of a seismic triplication event, which we call the T-event. The depth at which the T-event maps is shallow (200–500 m below seafloor) in high-velocity regions and deeper (600–1400 m) in low-velocity regions. We also find that the currently active strike-slip fault has been active since at least 0.26 Ma and has sliced the ridge. We image low-velocity pockets at the northern and southern limits of the median ridge that could represent the expression of the currently less active strike-slip faults.