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'Biomining' seaweed explored for critical minerals to improve domestic supply chains

Phys.org: Earth science - Wed, 08/20/2025 - 14:59
In a bright, open laboratory nestled along Washington State's Sequim Bay, among rows of glassware filled with seawater and green and purple seaweed, researchers are investigating a new way to produce the critical minerals that are vital to everyday life.

Ash dieback triggers hidden surge in carbon emissions from woodland soils, research shows

Phys.org: Earth science - Wed, 08/20/2025 - 14:17
Ash dieback and other tree diseases are resulting in significantly more greenhouse gas emissions than previously thought because a large amount of carbon is escaping from woodland soils, a study has found. This is in addition to carbon losses from tens of millions of dying trees and reduced removal of CO2 from the atmosphere due to the widespread deaths of mature ash trees.

By 2051, Emissions from Coal Mining on Federal Lands Could Drop by 86%

EOS - Wed, 08/20/2025 - 13:18
Source: Earth’s Future

Federal lands—which make up about 640 million acres, or 28%, of U.S. soil—are used for many purposes, including conservation, recreation, and extraction of resources such as coal. Greenhouse gas emissions are released throughout the life cycle of coal use, including during its mining, transport, and combustion.

Merrill et al. estimated the amount of coal production and coal-related greenhouse gas emissions from federal lands from 2024 to 2051. Specifically, they focused on emissions of carbon dioxide, methane, and nitrous oxide from 30 existing mines on federal lands (excluding Native American lands) in six states.

Active mines, and some abandoned mines, generate fugitive emissions, or unintended emission leaks, via venting and drainage. To calculate fugitive greenhouse gas emissions of underground mines, the team used average emissions data from the five most recent years available (2016–2020). The researchers calculated emissions from surface mines using a method developed by the U.S. EPA.

To estimate transportation-related emissions, they turned to resources such as power plant coal receipts and coal mine news releases to find information about how far and by what means coal was transported. The team used information about coal composition and mine characteristics, along with public reports, to estimate the most likely end uses of coal, such as cement production, conversion into coke (a fuel used in iron ore smelting and blacksmithing), or, most commonly, combustion.

From their analysis, the researchers estimated that between 2024 and 2051, coal production from federal lands will decline to 14.2% of 2023 production levels. The fastest rates of decline will occur between 2037 and 2048 because of the anticipated closure of a number of coal power plants. In the same time period, greenhouse gas emissions from coal mining on federal lands are projected to decrease 86% from 2024 estimates. Most of this reduction, roughly 95%, would come from reducing end point combustion of coal.

The team noted that their work was based on information that existed at the beginning of 2024 and that their findings are subject to possible changes in land management decisions. They suggest that these estimations can be helpful as part of domestic and global decisionmaking around greenhouse gas emissions and the future use of coal. (Earth’s Future, https://doi.org/10.1029/2024EF005735, 2025)

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

Citation: Derouin, S. (2025), By 2051, emissions from coal mining on federal lands could drop by 86%, Eos, 106, https://doi.org/10.1029/2025EO250305. Published on 20 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.

Mysterious Fickle Hill earthquake in northern California may have unexpected source

Phys.org: Earth science - Wed, 08/20/2025 - 13:16
What lies beneath Fickle Hill in northern California? Maybe the answer to an earthquake mystery that has puzzled seismologists for decades.

Earth system models project start of Amazon dieback within 21st century

Phys.org: Earth science - Wed, 08/20/2025 - 13:14
The Amazon is the world's largest rainforest. It harbors immense biodiversity and plays a crucial role in the global climate system by storing vast amounts of carbon in its vegetation.

Mid-Career Book Publishing: Bridging Experience with Discovery

EOS - Wed, 08/20/2025 - 12:00
Editors’ Vox is a blog from AGU’s Publications Department.

By the middle stage of a scientist’s career, expertise and reputation have been established, creating space to test out fresh opportunities and expand one’s comfort zone. For three scientists who wrote or edited books as mid-career researchers, this professional stage was very much a “happy medium.” They describe honing their research interests, gaining more autonomy to mold their work life, and finding joy in new roles within and beyond academia. Among these new undertakings was writing or editing a book. In the second installment of three articles, scientists contemplate why a book project was the perfect addition to the dynamic mid-career stage of their professional journeys.

Gaye Bayrakci coedited Noisy Oceans: Monitoring Seismic and Acoustic Signals in the Marine Environment, a comprehensive review of the sources and impacts of different types of marine noise. Bethany Hinga authored Earth’s Natural Hazards and Disasters, a textbook about the science behind natural events and how to prepare for disasters. Tamie Jovanelly authored Iceland: Tectonics, Volcanics, and Glacial Features, which explores the dramatic forces that have shaped the Icelandic landscape. We asked these researchers what developments shaped their mid-career stage, how a book fit in with their other goals and responsibilities, and to what extent their books influenced their next steps.

How would you describe the middle stage of a scientist’s career?

It’s a stage where you’re trusted with responsibility, but you also have the freedom to shape your role.

GB: Mid-career is genuinely exciting. I’m no longer dealing with early-career uncertainty, but I’m still actively thinking about what I want to focus on in the years ahead. It’s a stage where you’re trusted with responsibility, but you also have the freedom to shape your role, whether that’s through supervision, strategic planning, or external engagement. That sense of possibility is one of the best parts of this stage. It is also when you begin to think more about legacy, considering the kind of contribution you want to make in the long run, and that adds meaning and motivation to the work.

BH: I think for a lot of scientists this is the time when research programs and professional relationships are well cemented, and they have a growing bench of graduate students they’ve trained and are moving out into the world to do great things. My experience was different. Ten years post-PhD, I was in higher education administration and starting to branch out into other areas of expertise related to that administrative work.

Why did you decide to complete a book project? Why at that point in your career?

TJ: I decided to write a book after leading a field studies course in Iceland for over a decade. Throughout this time, I noticed a significant gap in the textbook market. While several publications touched on Iceland’s volcanology at a basic level, none provided a comprehensive overview of the island’s tectonics, volcanics, and glacial features. Recognizing this need, I felt compelled to contribute a resource that would serve both educators and students in the field of geology. My prior course preparation not only solidified my understanding of Iceland’s unique geological landscape but also allowed me to organize this knowledge effectively.

It was a chance to do something creative rooted in my scientific discipline.

BH: I had a twelve-month position in Academic Affairs at my university and the students and faculty were only on campus for nine months. I had three months of the year with time on my hands and a deep desire to start on a book that had been simmering in my head for years. I also had incredibly talented colleagues who were willing to write chapters in areas I felt were important to include in the book, but I didn’t have the expertise or comfort level to write myself. It was a chance to do something creative rooted in my scientific discipline, and it was a welcome change of gears from my job during the academic year, which had nothing to do with my discipline.

GB: The idea came when someone in my professional network, Frauke Klingelhoefer, was invited by AGU to propose a book on short-duration or non-earthquake seafloor signals. She contacted me, and we quickly realized that a broader book on ocean noise would be more valuable. It is a timely topic, relevant to biology, climate, defense, and offshore infrastructure, yet still underrepresented in the literature. Frauke, being very busy, suggested we co-edit and encouraged me to take the lead. It felt like the right moment to take on a creative, community-focused project.

What were some benefits of doing a book as a mid-career researcher?

It helped me see connections across disciplines and engage with researchers I might not have otherwise worked with.

GB: Editing the book gave me a much broader view of how scientists use pressure and sound to study both the water column and the shallow subsurface. It helped me see connections across disciplines and engage with researchers I might not have otherwise worked with. It was also a chance to step back, reflect on my own work, and rethink my scientific direction. I’ve since started new collaborations and found ways to apply similar techniques in my projects. The process confirmed that there’s still so much space to grow at mid-career.

TJ: Writing a book as a mid-career researcher offers several significant benefits. First, at this stage in my career, I had successfully navigated key responsibilities toward earning promotion and tenure. With these milestones behind me, I had the freedom to pursue projects that genuinely interested me making the writing process very enjoyable. Second, after years of publishing scientific journal articles, I had honed essential skills in conducting literature searches, synthesizing scientific arguments, and formulating key questions. These competencies not only streamline the writing process but also bolstered my confidence as an author. I felt capable of presenting complex ideas in a manner that is accessible to a broader audience. Third, writing a book allowed me to establish myself as a thought-leader in my field. By compiling my insights and research findings into a cohesive monograph, I have solidified my reputation as an expert on specific topics. This has led to greater visibility within the academic community, opened doors with new collaborators, and presented countless speaking engagements and other professional opportunities.

What advice would you give to mid-career researchers who are considering writing or editing a book?

Writing a book is an excellent way for a mid-career researcher to fall in love with science again.

TJ: My advice for any mid-career researcher considering writing a book is to realize that you are not an expert before you write the book; you are an expert after you write the book. Tackling a book project with this mentality automatically provides you with some grace when you are asking questions that you don’t yet have the answers to. Writing a book is an excellent way for a mid-career researcher to fall in love with science again, and it will make you a better classroom teacher and science communicator as a result.

BH: This is really the perfect time in your career to take on a project of this type!

—Gaye Bayrakci (g.bayrakci@noc.ac.uk, 0000-0003-1851-5021), National Oceanography Centre, UK; Bethany Hinga (Beth.Hinga@Newberry.edu, 0000-0003-0694-5331), Newberry College, USA; and Tamie Jovanelly (tamiejovanelly@gmail.com, 0000-0002-4374-0266), Adventure Geology Tours, USA

This post is the second in a set of three. Learn about leading a book project as an early-career researcher. Stay tuned for the third installment.

Citation: Bayrakci, G., B. Hinga, and T. Jovanelly (2025), Mid-career book publishing: bridging experience with discovery, Eos, 106, https://doi.org/10.1029/2025EO255026. Published on 20 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.

Fast matter-antimatter separation via Weibel-induced plasma filamentation

Physical Review E (Plasma physics) - Wed, 08/20/2025 - 10:00

Author(s): Oliver Mathiak, Lars Reichwein, and Alexander Pukhov

The separation of matter and antimatter in a plasma can be driven by the growth of the Weibel instability. The authors show this effect in a plasma of protons and antiprotons with a relativistic stream of electrons and positrons, by means of particle-in-cell simulations supported by analytical considerations.

#AdvancingField #OpenDebate


[Phys. Rev. E 112, 025208] Published Wed Aug 20, 2025

Industry managed forests more likely to fuel megafires, study finds

Phys.org: Earth science - Wed, 08/20/2025 - 09:10
The odds of high-severity wildfire were nearly one-and-a-half times higher on industrial private land than on publicly owned forests, a new study found. Forests managed by timber companies were more likely to exhibit the conditions that megafires love—dense stands of regularly spaced trees with continuous vegetation connecting the understory to the canopy.

The influence of the fractal dimension on the complex conductivity of porous materials

Geophysical Journal International - Wed, 08/20/2025 - 00:00
SummaryThe bulk component of the electrical conductivity of a porous material is related to the (connected) porosity and saturation by power-law functions defining the first and second Archie's laws. Recently, it was shown that for porous materials with fractal characteristics, the power-law exponent of Archie's law could be related to the fractal dimension of such materials. Similarly, the real and imaginary parts of the complex-valued surface conductivity are not just proportional to the specific surface area and saturation of the material but to power law functions of these properties defining two additional “interfacial” Archie's laws, which are called the third (saturated case) and fourth (unsaturated case) Archie's laws in this paper. These new laws have been poorly recognized and studied so far. A number of porous materials and especially clay-rich media are multiscale materials characterized by broad distributions of particle and pore sizes. We extend Archie's laws concept to describe the complex conductivity of such materials. We use both numerical simulations in fractal porous materials as well as published experimental datasets to propose a unified physical interpretation of the exponents entering the four Archie's type power-law relationships, which offer an updated complex conductivity model for natural porous media.

Variation in the Main Himalayan Thrust (MHT) within the Central Himalayan Seismic Gap using teleseismic P- wave coda autocorrelation: Implications for seismic hazard

Geophysical Journal International - Wed, 08/20/2025 - 00:00
SummeryThe seismic hazard due to higher magnitude Himalayan earthquakes largely depends on the geometry of the underthrusting Indian Plate beneath the Himalayas, i.e., the Main Himalayan Thrust (MHT). For an objective assessment of seismic hazard in the central Himalayan seismic gap, we determine the geometry of the Main Himalayan Thrust (MHT) along 4 ∼SW-NE oriented arc-normal seismic profiles covering the central Himalayan seismic gap. We use teleseismic P- wave coda autocorrelation on waveforms recorded at 117 broadband seismic stations spread along these profiles, with an interstation spacing of 3-5 km. The results show that along these seismic profiles, the MHT is mostly of flat-ramp-flat geometry. However, the mid-crustal ramp of the MHT shows variations in its location, dip angle, and width. We also observe variations in the MHT near the Main Frontal Thrust (MFT) and Main Boundary Thrust (MBT). The observed variations in the MHT geometry within the central Himalayan seismic gap thus suggest the possibility of along-strike segmentation of the Himalayan arc, and different seismic hazard scenarios may be present during any possible higher magnitude earthquake in the central Himalayan seismic gap.

Automatic picking of multi-modal Rayleigh-wave dispersion curves from multi-component data with an energy-density-based clustering method

Geophysical Journal International - Wed, 08/20/2025 - 00:00
SummaryRayleigh wave is widely used for characterizing shallow subsurface structures. The conventional Rayleigh-wave methods rely on the manual picking of dispersion curves, and the dispersion curves of multi-component data are usually merged manually. The manual processing of multi-component Rayleigh waves reduces the efficiency of the method, especially when the data size and the number of modes are large. To overcome these limitations, we develop an energy-based clustering method, namely the Energy-Density-Based Spatial Clustering of Applications with Noise (E-DBSCAN) algorithm. The E-DBSCAN algorithm extracts energy clusters and dispersion curves from a single dispersion image. It considers the dispersion-energy values of the surface wave and is able to pick the dispersion curve more reliably compared with the conventional DBSCAN algorithm. We propose a two-step clustering approach for the automatic picking of multi-mode dispersion curves from multi-component data: we first extract the energy clusters in the dispersion spectra of horizontal- and vertical-component data using E-DBSCAN, respectively, and combine them in the frequency-velocity domain. Then we extract multi-modal dispersion curves from the combined multi-component energy clusters with E-DBSCAN or DBSCAN. Numerical results show that our proposed method has fairly high accuracy and estimates more abundant multi-modal dispersion curves than the single-component method. Two field examples, including an active-source and an ambient-noise dataset, prove the validity of our method and the outperformance of multi-component results compared with the single-component results. Our proposed method has a relatively low dependence on parameter selection and is also applicable to multi-offset data, which is valuable for picking multi-modal dispersion curves.

Reciprocity and representation theorems for rotational seismology

Geophysical Journal International - Wed, 08/20/2025 - 00:00
SummaryRecently, there has been an increasing interest in employing rotational motion measurements for seismic source inversion, structural imaging and ambient noise analysis. We derive reciprocity and representation theorems for rotational motion. The representations express the rotational motion inside an inhomogeneous anisotropic earth in terms of translational and rotational motion at the surface. The theorems contribute to the theoretical basis for rotational seismology methodology, such as determining the moment tensor of earthquake sources.

Exploring the dynamic interactions between El Niño-Southern Oscillation and tropical basins

Phys.org: Earth science - Tue, 08/19/2025 - 19:52
Earth's climate is a dynamic system of interconnected physical processes and events occurring around the globe. Many of these processes are coupled so that changes in one event or process in one geographical area will result in changes in many other geographical areas. It is one of the challenges in climate science to understand the various processes, how they affect each other and how they change over time and space.

Q&A: Wildfire char shows promise for reducing atmospheric methane emissions

Phys.org: Earth science - Tue, 08/19/2025 - 18:09
It's hard to believe that there is anything positive that could come out of wildfires. They have devastated homes, taken lives, erased memories, leveled cities and destroyed our forests and wildlands. But a University of Delaware professor has found that there is something of value to be learned from what's left behind in the remnants.

Why does Australia have earthquakes? The whole continent is under stress from distant forces

Phys.org: Earth science - Tue, 08/19/2025 - 15:30
Last Saturday at 9:49am local time, a magnitude 5.6 earthquake occurred about 50km west of Gympie in Queensland. The earthquake was experienced as strong shaking locally, but did not produce any significant damage, likely because of the remote location of the epicenter.

Svalbard lost 1% of its ice in the summer of 2024, more than any year on record

Phys.org: Earth science - Tue, 08/19/2025 - 15:30
Svalbard, an Arctic archipelago that is technically a part of Norway, lies about halfway between the northernmost part of Norway and the North Pole. Currently, about 60% of Svalbard's surface is covered in glaciers, but these glaciers are melting rapidly. During the summer of 2024, Svalbard experienced a record-breaking heat wave that melted more of its glaciers than ever before.

Trees in the tropics cool more, burn less: For fire suppression and cooling, location is everything

Phys.org: Earth science - Tue, 08/19/2025 - 15:28
More trees will cool the climate and suppress fires, but mainly if planted in the tropics, according to a new UC Riverside study.

In Africa, heat waves are hotter and longer than 40 years ago, researchers say

Phys.org: Earth science - Tue, 08/19/2025 - 14:37
Heat waves—prolonged periods of abnormally hot weather—influence egg prices, energy bills and even public transit. And they're becoming more common as temperatures increase.

North Pacific waters are acidifying more rapidly below the surface, research reveals

Phys.org: Earth science - Tue, 08/19/2025 - 14:19
Carbon dioxide in the atmosphere enters the ocean at the surface and has been increasing the acidity of Pacific waters since the beginning of the industrial revolution over 200 years ago. A new study, led by University of Hawai'i at Mānoa oceanographers, revealed that the ocean is acidifying even more rapidly below the surface in the open waters of the North Pacific near Hawai'i.

Where the Pigs and Buffalo Roam, the Wetlands They do Bemoan

EOS - Tue, 08/19/2025 - 13:29
Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Journal of Geophysical Research: Biogeosciences

The prevailing view of mammal activity in ecosystems is that they have marginal impacts to services like greenhouse gas emissions. However, that is not always the case, especially with large, feral ungulates. In northern Australia, the indigenous Yolŋu peoples connect and rely on coastal wetlands for spiritual connection, tourism, fisheries, and crocodile egg harvesting. These wetlands, however, suffer damage from invasive pigs and buffalo. The Yirralka Rangers of the region attempt to control these from the air.

Crameri et al. [2025] partnered with the local community to evaluate the impact of these feral ungulates on wetland greenhouse gas emissions and carbon stocks, an ecosystem service growing in value for climate change mitigation. Fenced enclosures allowed the authors to reveal a fourfold increase in carbon dioxide and methane emissions in unfenced areas, while fenced areas increased in belowground biomass with limited impact on soil organic carbon. The work demonstrates how research partnerships with local communities, as documented in the article’s Inclusion in Global Research statement, can support local land stewardship and contribute to global conservation and climate mitigation efforts.

Citation: Crameri, N. J., Mununggurr, L., Rangers, Y., Gore, D. B., Ralph, T. J., Pearse, A. L., et al. (2025). Feral ungulate impacts on carbon cycling in a coastal floodplain wetland in tropical northern Australia. Journal of Geophysical Research: Biogeosciences, 130, e2025JG009056. https://doi.org/10.1029/2025JG009056

—Ankur Desai, Associate Editor, JGR: Biogeosciences

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.

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