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On March 28, 2025, a major earthquake with a moment magnitude (Mw) of 7.7 struck Mandalay, central Myanmar (referred to as the 2025 Myanmar earthquake). This event caused severe shaking and substantial damage in Myanmar and neighboring countries. Aftershock distribution extended southward from the epicenter, indicating predominant southward rupture propagation.

Tsunami earthquakes are characterized by the generation of disproportionately large tsunamis relative to the observed ground shaking, complicating timely evacuation efforts. Understanding their generation mechanisms and associated risks is therefore critical.

Scientists have found evidence that the Asian continent was free of permafrost all the way to its northerly coast with the Arctic Ocean when Earth's average temperature was 4.5˚C warmer than today, suggesting that the whole Northern Hemisphere would have also been free of permafrost at the time.

University of Leicester-led research has revealed the start of industrial deforestation of the Malaysian rainforest and its long-lasting impact on coastal ecosystems in the skeletons of corals.

Ship traffic in shallow areas, such as ports, can trigger large methane emissions by just moving through the water. Researchers in a study, led by Chalmers University of Technology in Sweden, observed 20 times higher methane emissions in the shipping lane compared to nearby undisturbed areas.

Geologists from the University of Hong Kong (HKU) have made a breakthrough in understanding how Earth's early continents formed during the Archean time, more than 2.5 billion years ago. Their findings, recently published in Science Advances, suggest that early continental crust likely formed through deep Earth processes called mantle plumes, rather than the plate tectonics that shape continents today.

Floods are some of the most devastating natural disasters communities in the United States face, causing billions of dollars of damage annually, according to the National Weather Service. A group, including several researchers at Penn State, recently developed a computational model to streamline flood prediction in the continental United States.

About 600 miles off the west coast of Africa, large clusters of thunderstorms begin organizing into tropical storms every hurricane season. They aren't yet in range of Hurricane Hunter flights, so forecasters at the National Hurricane Center rely on weather satellites to peer down on these storms and beam back information about their location, structure and intensity.

As winter gives way to spring, seasonal snowpack in the American West begins to melt.

Though some of that melt flows over and through shallow alpine soil, new research shows that much of it sinks into bedrock where it percolates for years before resurfacing. Fresh snowmelt makes up less than half of the water in the region’s gushing spring streams, according to the study.

The new finding could improve water resources forecasts. Hydrologic models, which inform the forecasts, largely overlook groundwater contributions and assume the spring’s heavy flows come directly from seasonal snowmelt.

The authors of the study, published in Communications Earth & Environment, used a radioactive isotope of hydrogen known as tritium to measure when the water in 42 western U.S. catchments fell as precipitation.

They found that during late winter, when rain and snowmelt were scarce and streams were fed primarily by groundwater, the water fell as precipitation an average of 10.4 years ago. Even during spring, when the same streams were overflowing with fresh runoff, their chilly waters had an average age of 5.7 years, still indicating significant contributions from groundwater.

A Subterranean Bucket

Hydrologic models typically simulate mountains as impermeable masses covered with a thin sponge of alpine soil, said the study’s first author, Paul Brooks, a hydrologist at the University of Utah. The sponge can absorb some water, but anything extra will quickly drain away.

“Snowmelt is being recharged into groundwater and is mobilizing groundwater that has been stored over much longer [periods].”

However, over the past few decades, scientists have uncovered a steady stream of hints that mountains may store huge volumes of water outside their spongy outer layer. Many high-elevation creeks carry dissolved minerals similar to those found in groundwater, suggesting a subterranean origin. Scientists studying healthy alpine ecosystems in arid conditions have wondered whether plants were tapping into a hidden reservoir of water.

Though snowmelt and rainfall immediately increase streamflow, the relationship is not intuitive. “What appears to be happening is that snowmelt is being recharged into groundwater and is mobilizing groundwater that has been stored over much longer [periods],” said James Kirchner, a hydrologist at Eidgenössische Technische Hochschule Zürich who was not involved in the research.

In areas where the mountains were made of porous sandstone, waters monitored in the new study were much older. In one such stream, the average age of water in winter was 14 years.

Mountains are “more like a bucket with a sponge on top.”

The authors were able to convincingly demonstrate the age of the flows because they used tritium, Kirchner said. Though scientists have previously used tritium to date water from individual streams and large bodies such as oceans and lakes, this study is the first to use tritium to date alpine groundwater and snowmelt across multiple catchments, Brooks said.

On the basis of historic flows, annual precipitation, and the ages of the stream water, the mountains could store an order of magnitude more water than accounted for in current models, Brooks said. As opposed to the impermeable masses in traditional models, he explained, mountains are “more like a bucket with a sponge on top.”

This finding could change how scientists think about the alpine water cycle. “If precipitation takes, on average, years to exit as streamflow, that means that streamflow in any one year is a function of years of climate and weather,” Brooks said. That means forecasters should consider more than just the most recent snowpack when estimating spring flows and potential flooding.

But further research is needed to unearth the role mountains play in water storage. The current study is limited because it covers only snowmelt-driven streams in the arid western United States, Kirchner said. Things might work differently in wetter places, he added.

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

Citation: DeGraff, M. (2025), Years-old groundwater dominates spring mountain streams, Eos, 106, https://doi.org/10.1029/2025EO250238. Published on 3 July 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.

In the face of rising atmospheric carbon dioxide, the Gulf of Maine is thought to be particularly vulnerable to ocean acidification. Its vulnerability has to do with temperature: The waters of the gulf are cold, and cold water dissolves carbon dioxide more easily than warmer water does. Increased carbon dioxide decreases the pH of the ocean (making it more acidic), a concern for the health of the region’s ecosystems as well as its lucrative shellfish industry.

But determining seawater chemistry is complicated. It requires advanced equipment and the assessment of complex physical, chemical, and biological processes. Until now, no long-term data existed to put individual measurements into context, so scientists did not know how acidity in the region’s waters was trending.

Using ocean chemistry recorded in algae, researchers have now constructed a nearly 100-year history of acidity (pH) in the region. The analysis, published in Scientific Reports, shows that ocean acidification, seen around the world, has been delayed in the gulf.

The Gulf of Maine is fed by three offshore water masses: icy, acidic northern waters from the Scotian Shelf and Labrador Current and warm, alkaline Gulf Stream waters. It’s also bordered by thousands of kilometers of shoreline to the west, and its estuaries and inshore waters receive significant riverine runoff.

The group expected to see pH fluctuate in the gulf, given the different factors affecting ocean chemistry and human-driven increases in atmospheric carbon dioxide, said Joseph Stewart, a geochemist from the University of Bristol in the United Kingdom and study coauthor. Data from 2011 to now, collected in Maine’s Casco Bay by a local nonprofit, show an increase in acidity in that coastal area. But that time frame is too short to determine long-term trends, according to the study authors.

Ocean Chemistry Recorded in Algae

Crustose coralline algae live for about 40 years in coastal areas of the Gulf of Maine, the southern limit of their range. These cold-loving algae encrust rocks and grow in seasonal increments, leaving growth bands akin to tree rings in their calcified skeletons. They are highly sensitive to changes in pH and serve as a record for past seawater carbon dioxide concentrations.

Using samples of the algae collected from several locations, the team reconstructed a timeline that spanned from 1920 to 2018.

“We’ve been measuring temperature for a long time, but we have not been measuring seawater pH for very long. It’s a very complicated, hard measurement.”

“We’ve been measuring temperature for a long time, but we have not been measuring seawater pH for very long. It’s a very complicated, hard measurement,” said Branwen Williams, a climate scientist at Claremont McKenna College in California and coauthor of the study. “So records like this are really valuable to get a sense of the variability that exists, particularly in these areas with people,” she said.

To the researchers’ surprise, the algae recorded a historic trend of relatively low pH in surface seawater, about 7.9, with a slight increase of 0.2 pH unit over the past 40 years. (On average, ocean water currently has a pH of around 8.1.) That move toward slightly more basic conditions was counterintuitive.

“We were somewhat surprised by that result, but then it made a lot of sense when we put it in the context of how temperature was changing and how nutrients were changing, and the timing of that change that had been previously documented in other papers,” Stewart said.

Starting around 2010, waters in the Gulf of Maine warmed dramatically. The change was driven by the decreasing influence of frigid northern water masses and the rise of Gulf Stream waters, which are not only warm but also alkaline. These waters seem to act as a buffer and delay the onset of ocean acidification.

Warming Waters

Ocean circulation–driven buffering effects will, at some point, reach their limits, researchers said. The ocean’s uptake of rising amounts of atmospheric carbon will persist, however, and leave the region’s ecosystems and economy vulnerable to the effects of acidification.

Ocean acidification presents one more challenge to the gulf’s coastal economy and its commercial fisheries, which stretch from Cape Cod to Nova Scotia. Ecosystems in the Gulf of Maine already face threats from disease, warming waters, habitat degradation, and invasive species. The added threat of acidification may push individual species past their ability to persist and redefine the biotic and abiotic factors contributing to those species’ ecosystems—a tipping point.

“It’s not just pH on its own that’s going to cause the ecosystem tipping point to occur, but a combination of pH and temperature, and both of those things are changing. The more data we have to understand the systems, all those different factors, the better,” said study coauthor Michèle LaVigne, an ocean scientist at Bowdoin College in Maine.

This and other studies provide insight into acidification trends, but the challenge of understanding and addressing competing factors influencing ocean pH feels intractable, said Damian Brady, an oceanographer at the University of Maine who was not involved in the study. “The dynamics are such that we have these countervailing forces all the time. We have these rises in total alkalinity from offshore source water, increases in temperature, while also, we as a species increase the carbon dioxide that goes in there,” he said. “It’s really complex.”

—Kimberly Hatfield, Science Writer

Citation: Hatfield, K. (2025), Warming Gulf of Maine buffers ocean acidification—for now, Eos, 106, https://doi.org/10.1029/2025EO250239. Published on 3 July 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.

An international study has revealed how continental collisions may have supercharged the Earth's richest deposits of copper, a metal critical for clean energy technologies and global infrastructure.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances

Waves in the polar jet stream over eastern North America are often responsible for cold air outbreaks and extreme winter storms. A 1990-2010 increase in jet stream waviness has, controversially, been linked to unusually rapid warming in the Arctic and has been thought to foreshadow a rise in extreme weather as climate change progresses. However, the United States “warming hole” —an enigmatic 1958-1988 cooling trend centered over the eastern U.S.— has also been linked to an increase in jet stream waviness several decades before the 1990s shift in waviness. This timing difference raises questions about whether the jet stream behavior since the 1990s is historically unusual.

Chalif et al. [2025] leverage information from long-term climate reconstructions and find that the jet stream was wavier than it is today during many periods of the 20th century and was the dominant factor driving the winter warming hole. The results highlight the strong relationship between jet stream waviness and eastern U.S. climate, and question whether accelerated Arctic warming is responsible for recent jet stream waviness.

Citation: Chalif, J. I., Osterberg, E. C., & Partridge, T. F. (2025). A wavier polar jet stream contributed to the mid-20th century winter warming hole in the United States. AGU Advances, 6, e2024AV001399. https://doi.org/10.1029/2024AV001399

—Alberto Montanari, Editor-in-Chief, 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.

In April 2025, I recorded 41 fatal landslides that cost 107 lives.

I’m somewhat behind with posting updates on global fatal landslides due to other workload pressures – please accept my apologies. Please be assured that I’m still collecting the data and that I will make a summary available as soon as I can.

Somewhat belatedly, here is a summary for April 2025 (the same report for the previous month is available here). As always, a reminder that this is a dataset on landslides that cause loss of life, following the methodology of Froude and Petley (2018). At this point, the monthly data is provisional.

The headlines are as follows. In April 2025, I recorded 41 fatal landslides that cost 107 lives. The April Average for 2004 to 2016 is 28 fatal landslides, so this is once again substantially above the long term mean. In the exceptional year of 2024, I recorded 40 landslides, so as at 30 April 2025, the cumulative total is proving to be comparable to the prior year. This is a little bit surprising.

Loyal readers will know that my preferred way of displaying these data is using pentads – 73 five day blocks over the course of the year. The end of April takes us to pentad 24:-

The number of fatal landslides to the end of April 2025, displayed in pentads. For comparison, the long term mean (2004 to 2016) and the exceptional year of 2024 are also shown.

As the graph shows, the cumulative total number of fatal landslides to the end of April 2025 has tracked in a very similar way to April 2024. The trend is very substantially higher than for the long term average. But note also that 2024 saw a very early transition to the much higher event rate through the Northern Hemisphere summer (in 2024 this occurred in the latter part of April, the norm is at least a month later). At the end of April 2025, it was too early to tell whether this would be replicated.

I find this continued high rate of global fatal landslides through April 2025 quite surprising, but global temperatures have remained high. As the US Government dismantles its climate infrastructure (an act of pure vandalism), we are increasingly reliant on data being provided elsewhere. Fortunately, the European Copernicus Clime Change Service system remains wonderful and fully available. This shows that:

“April 2025 was the second-warmest April globally, with an average ERA5 surface air temperature of 14.96°C, 0.60°C above the 1991-2020 average for April. April 2025 was 0.07°C cooler than the record April of 2024, and 0.07°C warmer than the third warmest of 2016.”

Thus, the high event rate for fatal landslides may be associated with the continued high global temperatures, and thus high peak rainfall intensities, through the early part of 2025.

Reference

Froude M.J. and Petley D.N. 2018. Global fatal landslide occurrence from 2004 to 2016. Natural Hazards and Earth System Science 18, 2161-2181. https://doi.org/10.5194/nhess-18-2161-2018

Return to The Landslide Blog homepage Text © 2023. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

On 28 November 1966, an American airplane flies over the Antarctic Peninsula just south of the southernmost tip of Chile. On board is a photographer, probably from the U.S. Navy, whose job is to map the Antarctic landscape. But it turns out that the photographer is also documenting a very special situation that is in progress. He shoots an aerial photo of the Wordie Ice Shelf, which, 30 years later, has almost vanished after a total collapse.

Deep below the surface of the ocean, bacteria and critters that feed off nutrients spouting from hydrothermal vents met with a sudden wave of volcanic sediment, leaving them suffocated.

Compared to single-channel meandering rivers, multichannel braided rivers are often found in environments with sparse vegetation and coarse, shifting bars of sediment. Past research has called the way in which the paths of braided rivers shift over time "chaotic" because their migration depends on many factors, including river shape and changing water levels.

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

In the latest move in a months-long attack on climate science funding, the Trump administration released a budget document on 30 June that calls for zero funding for climate research and the elimination of a slew of NOAA services, including the agency’s climate laboratories, regional climate data efforts, tornado and severe storm research, and partnerships with other institutions.

The budget, proposed for fiscal year 2026, also calls for a reduction in NOAA’s full-time staff by more than 2,000 people. 

The Office of Oceanic and Atmospheric Research (OAR) would be eliminated under the proposed budget. OAR coordinates and performs NOAA’s climate and weather research.

“With this termination, NOAA will no longer support climate research grants,” the proposal states.

The proposed NOAA budget for 2026 contains the literal line:Total, Climate Research: $0www.commerce.gov/sites/defaul…

— Robert Rohde (@rarohde.bsky.social) 2025-06-30T23:25:38.113Z

“The idea [that] these labs would be completely wiped out is surreal and dangerous,” Dan Powers, executive director of CO-LABS, a science advocacy group, told Colorado Public Radio. 

The proposal would also eliminate funding for all of OAR’s climate and weather cooperative institutes—partnerships between the agency and other research institutions, including universities. One such partnership is the Mauna Loa Observatory in Hawaiʻi, an atmospheric research station best known for its measurements of atmospheric carbon dioxide.

Another is the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder, which houses the National Snow and Ice Data Center. The center tracks critical snow and ice observations used to monitor the impacts of climate change. The center had already halted maintenance for some of its data products after losing support from NOAA in May.

It is difficult to describe just how disastrous it would be if just-released NOAA budget proposal (or even large portions) were to be enacted: It would involve a wholesale dismantling (decimation, really) of entities relevant to weather, climate, & ocean research & prediction.

— Daniel Swain (@weatherwest.bsky.social) 2025-07-01T17:18:29.000Z

Additional programs slated to lose funding include the National Sea Grant College Program, the National Oceanographic Partnership Program, Species Recovery Grants, Climate Competitive Research, and Regional Climate Data and Information. 

The proposal also calls for the elimination of some environmental restoration and research programs, including the Pacific Coastal Salmon Recovery Fund, which had been used to restore 3,624 acres (1,467 hectares) of salmon habitat and enable salmon to travel hundreds of miles to their spawning streams in 2023, according to Oregon Public Radio. 

 
Related

•  NOAA FY26 Proposed Budget
•  New NOAA Document Spells Out Further Deep Trump Cuts
•  Proposed NOAA Budget Would Shutter Boulder’s World-Class Climate Research Laboratories
•  Get Involved: AGU Science Policy Action Center
 

Whether the proposed budget becomes a reality will be decided by Congress.

The future of much of NOAA’s climate and weather research and monitoring has been uncertain for months as the agency has decommissioned datasets, put some of its weather alert services on hold temporarily, and faced layoffs. 

In June, the agency announced that data from three satellites used in monitoring hurricanes would not be available to researchers after 30 June. Then, on the day of the deadline, they reversed course, extending the data availability through 31 July. Scientists expressed concern that extending the data availability still would not mean the data would be available during the peak hurricane months of August, September, and October.

—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
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Young forests regrowing from land where mature woodlands have been cut down have a key role to play in removing billions of tons of atmospheric carbon dioxide (CO2) and combating climate change, a new study reveals.

A new study led by a University of California, Irvine scientist reveals that airlines can make smarter tradeoff decisions to cut aviation's warming impact. The research, published in the journal Nature, offers hopeful news for the future of air travel and climate action.

Irina Marinov, associate professor at the Department of Earth and Environmental Science, leads a research community focused on understanding global climate impacts, risks, and vulnerabilities to enable local action.