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Asia steps into the global carbon cycle conversation

Phys.org: Earth science - Thu, 08/21/2025 - 08:00
A deeper look into carbon flux is now possible—thanks to a deep pool of scientific collaboration. And for once, the spotlight is on Asia.

A 2022 Pacific volcano eruption made a deep dive into Alaska

Phys.org: Earth science - Thu, 08/21/2025 - 05:57
Atmospheric waves from a massive 2022 South Pacific volcanic eruption created seismic waves that penetrated Earth to at least 5 kilometers in Alaska, creating an opportunity to employ an unusual method of peering into the state's deep subsurface.

Seismic attenuation along an oblique continental transform: Central Alpine Fault, New Zealand

Geophysical Journal International - Thu, 08/21/2025 - 00:00
SummaryNew Q (1/attenuation) models of the Central Alpine Fault provide unprecedented resolution to 20 km depth by incorporating new t* measurements from dense temporary seismograph deployments in the area. The models reveal significant heterogeneity in the crust, with the main Q features broadly similar along-strike the Alpine Fault but varying at length scales of 10-30 km. Accounting for heterogeneity is an important step towards understanding the seismic cycle of M7+ Alpine Fault earthquakes. Our models show the Alpine Fault as a southeast-dipping zone of very (<300) to moderately (600-900) low Q, contrasting sharply with high Q values (Qp>600, Qs>1000) within the Western Province bedrock and high Q values (Qp∼900, Qs∼1200) associated with uplifted Alpine schists to the east. The wealth of previous geologic and geophysical studies along this section of the Alpine Fault support a detailed interpretation of the observed Q values. We interpret the low Q values along the Alpine Fault as resulting from enhanced fracturing within the brittle crust with a proportion of these fractureslikely filled with fluids, which further enhance seismic attenuation through viscous dissipation. In the ductile crust (below ∼8 km depth), low Q values (<400) are likely predominantly caused by grain-size reduction from very high total shear strain and by small amounts of metamorphic fluids. Low Q values of 200-400 at 20-40 km depth downdip of the Alpine Fault and the generally low Q (<600) within the crustal root farther from the Alpine Fault, suggest increasing role of metamorphic fluids relative to that of grain-size reduction with depth and distance from the fault. The updated model also reveals a newly identified zone of low Q east of the Main Divide, approximately 40 km southeast of the Alpine Fault trace. This zone of low Q indicates significant strain accumulation on faults striking along the eastern flank of the Southern Alps, some of which have produced M6+ earthquakes in recent history. These faults represent a considerable seismic hazard for the South Island. The improved dataset and recent velocity models from temporary deployments also allow us to investigate the influence of the initial velocity model on the resulting t* measurements and Q models.

Ozone will warm planet more than first thought, study finds

Phys.org: Earth science - Wed, 08/20/2025 - 23:10
The world will warm more than expected due to future changes in ozone, which protects the Earth from harmful sun rays but also traps heat as it is a greenhouse gas.

Microbial carbon use efficiency rises after abrupt permafrost thaw, study finds

Phys.org: Earth science - Wed, 08/20/2025 - 20:33
Thawing permafrost is a major climate risk due to the associated release of carbon dioxide and other greenhouse gases (GHGs). However, new research by a team led by Prof. Yang Yuanhe from the Institute of Botany of the Chinese Academy of Sciences shows how microbes can stabilize soil carbon and potentially weaken the climate risk.

A new online tool can help streamline mineral identification

Phys.org: Earth science - Wed, 08/20/2025 - 20:08
Identifying a mineral might sound straightforward: Analyze its chemistry, compare it to known minerals and voilà. But for geologists, this process can be a time-consuming puzzle requiring specialized expertise and a lot of manual calculation.

By 2051, emissions from coal mining on federal lands could drop by 86%

Phys.org: Earth science - Wed, 08/20/2025 - 19:30
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.

Tree Rings Record History of Jet Stream-Related Climate Extremes

EOS - Wed, 08/20/2025 - 19:25
Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances

The degree to which global warming will affect atmospheric dynamics and, therefore, extreme weather is still uncertain. Broadman et al. [2025] find a clever way to reconstruct the history of one dynamical pattern that occurs when the jet stream forms five peaks and troughs around the Northern Hemisphere (referred to as a wave5 pattern). When this pattern occurs and persists during May-June-July there is a higher likelihood of co-occurring compound climate events — for example combined heat and drought in the southeastern United States, China, and southern Europe, but wetter than normal in Northwest Canada and Spain.

The authors combine multiple lines of evidence, tree ring records, climate reanalyses and models, to reconstruct variations in the strength of the early summer wave5 pattern and extend them over the past millennium. They find decadal variations but no significant trends in the occurrence of wave5 related climate extremes. However, a demonstrated link between La Niña conditions the preceding winter could potentially help in predicting the potential in some regions for extreme weather the following summer.

Citation: Broadman, E., Kornhuber, K., Dorado-Liñán, I., Xu, G., & Trouet, V. (2025). A millennium of ENSO influence on jet stream driven summer climate extremes. AGU Advances, 6, e2024AV001621. https://doi.org/10.1029/2024AV001621

—Susan Trumbore, Editor, AGU Advances

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.

New 'in and out' mechanism reveals how carbon dioxide reacts at water's surface

Phys.org: Earth science - Wed, 08/20/2025 - 19:20
Each year, billions upon billions of tons of CO2 are pumped into the atmosphere. A significant proportion of this ends up in Earth's oceans, where it can react with water to form carbonic acid, which causes ocean acidification.

Analysis of a Conceptual Multi-Node Flexible Small Body Lander: Bounce Suppression and Active Control

Publication date: Available online 6 August 2025

Source: Advances in Space Research

Author(s): Jingxuan Chai, Jie Mei, Youmin Gong, Xinyu Wu, Guangfu Ma, Weiren Wu

Distributed prescribed-time attitude consensus tracking control for multiple flexible spacecraft under time-varying actuator faults

Publication date: Available online 6 August 2025

Source: Advances in Space Research

Author(s): Shilei Cao, Man Yang, Jian Liu

Multiple source characteristics in coseismic ionospheric disturbances for the April 2, 2024 Hualien earthquake from GNSS observations

Publication date: Available online 6 August 2025

Source: Advances in Space Research

Author(s): Qingshan Ruan, Hang Liu, Jianghe Chen

Climate change amplifies extreme rains more than light precipitation, study finds

Phys.org: Earth science - Wed, 08/20/2025 - 18:31
Climate change enhances extreme rains more than the ordinary drizzle. New research shows that frontal rain increases the most, and illustrates why extreme rains caused by other phenomena are not equally affected.

Stylolites complicate sound wave propagation in sedimentary rock samples, affecting lab-scale monitoring

Phys.org: Earth science - Wed, 08/20/2025 - 16:30
Stylolites—irregular seams that occur in limestone—have been found to affect how acoustic waves move through rock samples. Laboratory-based insights from KAUST researchers offer an improved understanding of how these features impact acoustic imaging techniques, which are used to analyze induced microseismic events during hydraulic fracturing.

Study finds temporary slowdown in melting of Arctic sea ice

Phys.org: Earth science - Wed, 08/20/2025 - 15:07
Arctic sea ice has been melting at a slower rate for the past 20 years, despite human-induced global warming.

Abrupt Antarctic changes could have 'catastrophic consequences for generations to come,' experts warn

Phys.org: Earth science - Wed, 08/20/2025 - 15:00
Antarctica is at risk of abrupt and potentially irreversible changes to the continent's ice, ocean and ecosystems that could have profound implications for Australia and beyond, unless urgent action is taken to curb global carbon emissions.

'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.

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