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Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Geochemistry, Geophysics, Geosystems

More than a century ago, Alfred Wegener proposed that the Atlantic Ocean formed after North America drifted away from Africa and Eurasia. Much later, the theory of plate tectonics explained this movement as resulting from the formation of new oceanic crust in the space between the continents. But how did the the initial rift between the landmasses form, and how did it transition into a mid-ocean spreading ridge? Answers to these questions have remained elusive, partly because the time history of the rifting process has been difficult to decipher.

Foster-Baril et al. [2025] shed new light on the “rift to drift” transition by dating igneous rocks across a broad swath of the North American margin. They find that continental breakup and the subsequent transition to seafloor spreading was accomplished by three major pulses of magmatism. The first pulse was the largest, and involved extensive melting of mantle from below as the rift opened across a wide area. The second and third pulses, which were smaller, helped to localize the extensional deformation into a confined region. This localization facilitated the transition to symmetric seafloor spreading.

This sequence suggests that continental breakup happens across a much broader area, and over a longer time period, than was previously thought. It is still unclear if other continental breakup events also featured a series of magmatic pulses, or if the North American margin was unique in this way. Can this sequence also help us to understand “failed rifts” that never transition into seafloor spreading events? More studies that examine magmatism across broad regions of a rifting zone can help to answer such questions.

Citation: Foster-Baril, Z. S., Hinshaw, E. R., Stockli, D. F., Bailey, C. M., & Setera, J. (2025). Duration and geochemical evolution of Triassic and Jurassic magmatism along the Eastern North American Margin. Geochemistry, Geophysics, Geosystems, 26, e2024GC011900.  https://doi.org/10.1029/2024GC011900

—Clinton P. Conrad, Associate Editor, G-Cubed

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.

The earthquake near the east coast of the Kamchatka peninsula in Russia on July 30, 2025 generated tsunami waves that have reached Hawaii and coastal areas of the US mainland. The earthquake's magnitude of 8.8 is significant, potentially making it one of the largest quakes ever recorded.

Africa is a source of uncertainty in carbon cycle calculations. By some estimates, the continent's landscapes emit 2.1 billion tons more carbon dioxide than they take up each year—about equal to 1.5 times the annual emissions from coal-fired power plants. But other estimates are almost the complete opposite, suggesting that the continent's copious plant matter takes up 2.0 billion more tons of carbon dioxide per year than it releases.

In a world affected by climate change, the Southern Ocean plays an outsized role. It absorbs up to 40% of the human-caused emissions taken up by the oceans while also being home to some of the world's most vulnerable ecosystems.

A lot of the climate-altering carbon pollution humans release into the atmosphere by burning fossil fuels gets drawn into the Earth's oceans and landscapes through natural processes, mostly through photosynthesis, as plants turn atmospheric carbon dioxide into biomass.

Some of the rainiest places on Earth could see their annual precipitation nearly halved if climate change continues to alter the way ocean water moves around the globe.

Today at about 11:30am local time, a magnitude 8.8 earthquake struck off the coast of Russia's Kamchatka Peninsula in the country's far east.

Source: Global Biogeochemical Cycles

Africa is a source of uncertainty in carbon cycle calculations. By some estimates, the continent’s landscapes emit 2.1 billion tons more carbon dioxide than they take up each year—about equal to 1.5 times the annual emissions from coal-fired power plants. But other estimates are almost the complete opposite, suggesting that the continent’s copious plant matter takes up 2.0 billion more tons of carbon dioxide per year than it releases.

This uncertainty exists in part because the amount of carbon Africa takes up and emits varies greatly from year to year and partly because there is a dearth of available surface observations across the continent. Yun et al. investigated the reason for these fluctuations by applying a suite of atmospheric transport models to data from the Orbiting Carbon Observatory-2 (OCO-2), a satellite-borne instrument that tracks carbon dioxide emissions across Earth’s surface. By filling a critical observational gap over Africa, the OCO-2 satellite has allowed researchers to examine the continent’s carbon cycle in unprecedented detail.

Scientists previously suspected that temperature was the prime factor influencing plant growth and therefore carbon dioxide emissions. Instead, these researchers found that in Africa, moisture levels have a much bigger impact.

Different types of landscapes react to moisture quite differently, however. In shrublands and grasslands, plants take full advantage of water when it becomes available by increasing their mass with little energy expenditure. That reaction means that in wet years, shrublands and grasslands take up a lot of carbon and expel very little, substantially shifting the continent’s carbon flux. In contrast, forests and savannas emit and take up about the same amount of carbon in wet conditions; their overall impact on the continent’s carbon flux is therefore smaller.

These findings suggest an explanation for the long-standing question of why Africa was such a weak carbon sink during the El Niño event of 2015–2016. The continent was unusually dry during that time, leading to stalled plant growth and carbon uptake.

Rainfall is expected to change in Africa in the coming decades. Overall, moisture availability is expected to increase in the north and decrease in the south, but precipitation will likely be patchy, leading to discrete bursts of plant growth. The researchers emphasize that the long-term operation of OCO-2 is essential for monitoring how African ecosystems respond to these shifting rainfall patterns. Taking moisture fluctuations into account could enable more accurate predictions of how the carbon cycle will respond to climate change. (Global Biogeochemical Cycles, https://doi.org/10.1029/2025GB008597, 2025)

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

Citation: Sidik, S. M. (2025), When rain falls in Africa, grassland carbon uptake rises, Eos, 106, https://doi.org/10.1029/2025EO250277. Published on 30 July 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.

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.

One of the strongest earthquakes ever recorded struck off the eastern coast of Russia’s Kamchatka Peninsula Wednesday morning local time. Initially pegged at a magnitude-8.0, the quake was eventually upgraded to a magnitude-8.8. Adjusted magnitude estimates are not unusual for large earthquakes as more data become available.

If the estimate is not adjusted farther, the quake will be tied as the sixth largest earthquake ever recorded by modern instrumentation. The next largest instrumented event, a magnitude-9.0 quake, struck in 1952 roughly 45 kilometers to the northeast of the latest epicenter. 

U.S. Geological Survey “Did You Feel It?” reports captured the shaking that people on the Kamchatka Peninsula felt during the magnitude-8.8 earthquake. Credit: USGS, public domain

According to the U.S. Geological Survey (USGS), the recent earthquake likely struck along the Kuril-Kamchatka arc, which separates the Pacific tectonic plate and the Okhotsk microplate. Along the boundary, the Pacific plate is being subducted roughly to the west beneath the microplate. A preliminary USGS analysis of seismic data suggests the recent earthquake accommodated thrust motion, which is expected during slip along a subduction boundary.

On 20 July 2025, a magnitude-7.4 earthquake struck roughly 60 kilometers to the northeast of the recent epicenter. That quake occurred as a result of slip along a thrust fault of similar orientation. It’s proximity in location and time to the recent earthquake suggests the magnitude-7.4 quake was a foreshock to the magnitude-8.8 quake.  

Aftershocks are ongoing and will likely continue for weeks. More than 90 earthquakes of at least magnitude-4.4 have struck as of 1:00 p.m. UTC Wednesday, including a magnitude-6.9 shock followed a few minutes later by a magnitude-6.3 shock.

The magnitude-8.8 earthquake caused strong to extreme shaking in southern Kamchatka, according to USGS “Did You Feel It?” reports from the region.

 
Related

•  USGS Event Page: 2025 Kamchatka Peninsula, Russia Earthquake
•  U.S. Tsunami Warning Center
•  Japan Meteorological Agency Tsunami Warnings
 

The earthquake generated tsunami waves that spread across the Pacific. Wave heights of more than 3 meters inundated Severo-Kurilsk in the Kuril Islands south of Kamchatka, according to a Russian news agency.

The Japan Meteorological Agency issued tsunami warnings for much of the country’s Pacific coast. Waves up to 1.3 meters struck Kuji Port in northern Honshu. The U.S Tsunami Warning Center issued warnings for coastal Alaska, Hawaii, Washington, Oregon, and Northern California. Waves reached as high as 1.2 meters in Northern California. In Hawaii, waves reached 1.74 meters in Kahului on Maui and 1.5 meters in Hilo on the Big Island. 

Some injuries and no deaths have been reported.

—Jennifer Schmidt, Managing Editor

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Methane is a potent greenhouse gas with a much stronger short-term effect on warming than carbon dioxide. Over the near-term (20 years), 1 ton of methane has the warming effect of up to 84 tons of carbon dioxide, while over a hundred years, 1 ton of methane has the warming effect of about 28 tons of carbon dioxide. For this reason, controlling methane emissions is a high priority in limiting warming.

Recent climate-related crises—from severe storms and flooding to extreme heat—have raised new questions about how local governments communicate the risk of these crises and what they are doing to keep their citizens safe. To better understand what this communication looks like at local level, and the factors that may be shaping it, researchers from Drexel University analyzed climate resilience planning information available on the public-facing websites of 24 coastal communities in New Jersey that are contending with the effects of sea level rise.

Author(s): Yu-Xi Liu, Jin-Yue Geng, Hai-Xing Wang, Hao Yan, Xu-Hui Liu, Su-Rong Sun, Ao-wei Liu, and Tao Wu

Achieving uniform, stable, and reliable erosion of electrode materials is crucial for enhancing the performance and lifespan of vacuum-arc devices. This study investigates the rotation and erosion characteristics of cathode spots on Cu and Ti cathodes with various applied magnetic fields. The result…

[Phys. Rev. E 112, 015213] Published Wed Jul 30, 2025

A formidable new radar satellite jointly developed by the United States and India launched Wednesday, designed to track subtle changes in Earth's land and ice surfaces and help predict both natural and human-caused hazards.

A huge flood triggered by the rapid draining of a lake beneath the Greenland ice sheet occurred with such force that it fractured the ice above and burst out across its surface.

Wildfire season is no longer something that comes and goes; it's becoming a year-round concern. In BC, wildfires can shape the entire year, and we want to know what's coming, what's at risk and how to prepare.

A large region of unusually hot rock deep beneath the Appalachian Mountains in the United States could be linked to Greenland and North America splitting apart 80 million years ago, according to new research led by the University of Southampton.

В.В. Устинов, И.А. Ясюлевич

Хиральная спинтроника — новейшая перспективная ветвь квантовой электроники, в основе которой лежат спиновые транспортные явления в материальных объектах, обладающих хиральной симметрией. Данный обзор посвящён становлению и развитию хиральной спинтроники гелимагнетиков — материалов, характеризующихся спиральной магнитной структурой. В работе рассматриваются общие принципы описания электрического и спинового транспорта в проводящих кристаллах при наличии неоднородностей внешнего магнитного поля и/или внутренних магнитных полей обменного происхождения. Демонстрируется, что взаимодействие спинов электронов проводимости с пространственно-неоднородным полем обменного происхождения в гелимагнетиках даёт естественное объяснение двум экспериментально наблюдаемым спин-транспортным эффектам: электрическому магнитохиральному эффекту и кинетическому магнитоэлектрическому эффекту. Представлена оригинальная методика, позволяющая определять магнитную хиральность проводящих гелимагнетиков на основе экспериментальных исследований вышеупомянутых гальваномагнитных эффектов. Описывается построение теории эффекта передачи спинового момента в проводящих хиральных гелимагнетиках, включающей исследование влияния данного эффекта на намагниченность и электросопротивление гелимагнетиков. Продемонстрировано, что эффект передачи спинового момента в гелимагнетиках приводит к вращению спирали намагниченности под действием электрического тока. Это может быть использовано для создания новых устройств спиновой электроники, в которых проводящие гелимагнетики будут выступать в качестве основных функциональных компонентов.

QUT researchers have developed an advanced remote sensing method for accurately detecting and mapping Antarctica's delicate moss and lichen growth, the mainstays of the continent's fragile ecosystems. The research team also developed a way to survey Antarctica's vegetation that is noninvasive and will enable accurate surveys more quickly and cheaply than before. The paper is published in the journal Scientific Reports.

Researchers have devised a new machine learning method to improve large-scale climate model projections and demonstrated that the new tool makes the models more accurate at both the global and regional level. This advance should provide policymakers with improved climate projections that can be used to inform policy and planning decisions.

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.

On 28 July, more than 170 researchers sent a letter to National Science Foundation leaders and Congress, urging them to reconsider the decision to terminate the lease of the Nathaniel B. Palmer, the United States’ only Antarctic research vessel-icebreaker (RVIB) and a key part of science operations around the White Continent.

NSF revealed plans to end its lease with Offshore Service Vessels, the icebreaker’s owner, in its May budget request for 2026. An NSF spokesperson confirmed the plan to Science on 28 July, saying the lease would be terminated in October.

“This decision forecasts the decline of an exceptional history of U.S. scientific contributions,” the letter’s authors wrote.  

 
Related

•  Read the Letter to NSF
•  NSF Plans Abrupt End to Lone U.S. Antarctic Research Icebreaker
•  Confined at Sea at the End of the World
• Get Involved: AGU Science Policy Action Center
 

The Palmer has operated since 1992, spending much of its time in the Southern Ocean. There, scientists have collected data to gain understanding of Earth’s past, ocean processes, and the changing sea ice in Antarctica, including Thwaites Glacier—the so-called “doomsday glacier.” 

At a planning meeting earlier this summer, NSF officials said the R/V Sikuliaq would take over some of the work planned for the Palmer. But the Sikuliaq may not be up for the task: The ship is “wholly unsuited to most of what we do in Antarctica,” Julia Wellner, a marine geologist at the University of Houston, told Science. 

The research community has long been sounding the alarm about the dwindling U.S. Academic Research Fleet. Many vessels in the fleet have passed or are nearing the end of their original design lives, and although mid-life refits can extend their use, the yearslong process of designing, building, and outfitting a new vessel means the time to invest in replacements is now, according to ocean scientists.

“If federal budgets don’t keep pace to enable science, U.S. expertise in ocean science is largely going to continue to dwindle,” Paula Bontempi, an oceanographer at the University of Rhode Island, told Eos in January. “An investment in our ocean enterprise as a country is an investment in our shared future.”

Last year, NSF retired the JOIDES Resolution, a beloved ocean drilling vessel that had been conducting research for 4 decades, without plans to build or acquire a replacement. It also ended support for its other Antarctic research and supply vessel, the R/V Laurence M. Gould. In addition to ending operations of the Palmer, this year’s budget request also proposed to cut funding for a potential replacement vehicle for the ship.

“We urge reconsideration of the decision to terminate the lease of the RVIB Nathaniel B. Palmer, and the continued forward-looking development of the next generation of Antarctic research vessels that will continue US leadership, scientifically and geopolitically, in the high southern latitudes,” the letter’s authors wrote.

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

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.