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Chinese researchers have recently challenged the long-held belief that "all life depends on sunlight." In a study published in Science Advances, the researchers identified how microbes in deep subsurface areas can derive energy from chemical reactions driven by crustal faulting, offering critical insights into life deep below Earth's surface.

A new study published in the journal One Earth reveals that the way ecosystems collapse—abruptly or gradually—may depend on internal complexity, much like how magnetic materials behave under stress.

If you're in an earthquake-prone area and own an Android phone, it could save your life. It may even have already done so. The Android Earthquake Alert (AEA) system, which began in the U.S. in 2020 and has since expanded globally, sends an automatic alert approximately one minute before the ground starts shaking. That can be enough time to take cover or warn others nearby.

Artificial light and higher temperatures in cities may lengthen the growing season by up to 24 days, according to a new study in Nature Cities.

Previous studies have observed that plant growth starts earlier and ends later in cities than in rural areas. But these studies haven’t concluded whether this difference depends more on heat or light, both of which regulate the growing season and are amplified in urban centers.

The new study’s authors used satellite data to estimate nighttime light pollution in cities and pinpoint the start and end of the growing season. They found that the amount of artificial light at night plays a bigger role in growing season length than temperature does, especially by delaying the end of the season.

“This study highlights artificial light at night as a powerful and independent force on plant phenology,” said Shuqing Zhao, an urban ecologist at Hainan University in China who was not involved in the research. “It marks a major step forward in our understanding of how nonclimatic urban factors influence plant life cycles.”

City Lights Trick Plants

“Plants rely on both temperature and light as environmental cues to regulate their growth,” explained Lin Meng, an environmental scientist at Vanderbilt University and a coauthor of the study. In the spring, warmer temperatures and lengthening days signal to plants that it’s time to bud and produce new leaves. In the fall, colder, shorter days prompt plants to drop their leaves and prepare for winter.

“Plants evolved with predictable cycles of light and darkness—now, cities are flipping that on its head.”

But in cities, these essential cues can be disrupted. Cities are typically hotter than surrounding rural areas—the so-called urban heat island effect—and much brighter because of the abundance of artificial light. These disrupted cues “can trick plants into thinking the growing season is longer than it actually is,” Meng said. “Plants evolved with predictable cycles of light and darkness—now, cities are flipping that on its head.”

To assess how heat and light are affecting urban plants, Meng and her coauthors used satellite data from 428 cities in the Northern Hemisphere, collected from 2014 to 2020. For each city, the researchers analyzed correlations between the amount of artificial light at night (ALAN), air temperature, and the length of the growing season.

The scientists found that on average, the growing season started 12.6 days earlier and ended 11.2 days later in city centers compared with rural areas. ALAN apparently played an important role in extending the growing season, especially in the autumn, when ALAN’s influence exceeded that of temperature.

Anna Kołton, a plant scientist at the University of Agriculture in Krakow who was not part of the research, highlighted the significance of this result. “The impact of climate change, including increased temperatures on plant functioning, is widely discussed, but light pollution is hardly considered by anyone as a significant factor affecting plant life.” The new study is among the first to bring ALAN’s effects into the spotlight.

“Every Day Needs a Night”

“The extension of urban vegetation may at first glance appear positive,” said Kołton. But this positive impression is deceiving. In reality, an extended growing season “poses a threat to the functioning of urban greenery.”

Delaying the end of the growing season may be especially disruptive. In the fall, shortening days prompt plants to reduce their metabolic activity, drop their leaves, and toughen up their cell walls to withstand the coming winter. But if they are constantly stimulated by artificial light, Kołton pointed out, urban plants may miss their cue and be unprepared when the cold hits.

“Every day needs a night, and so do our trees, pollinators, and the rhythms of nature we all depend on.”

Longer growing seasons also affect animals and people. “Flowers might bloom before their pollinators are active, or leaf-out might not align with bird migration,” said Meng. “And for people, a longer growing season means earlier and prolonged pollen exposure, which can make allergy seasons worse.”

As cities become bigger and brighter, their growing seasons will likely continue to lengthen unless the impacts of ALAN are addressed. “The good news is that unlike temperature, artificial light is something we can manage relatively easily,” said Meng. She and Zhao both suggested that swapping blue-rich LED lamps for warmer LEDs (which are less stimulating to plants), introducing motion-activated or shielded lights, and reducing lighting in green spaces could limit light pollution in cities.

“Every day needs a night,” Meng said, “and so do our trees, pollinators, and the rhythms of nature we all depend on.”

—Caroline Hasler (@carbonbasedcary), Science Writer

Citation: Hasler, C. (2025), Artificial light lengthens the urban growing season, Eos, 106, https://doi.org/10.1029/2025EO250254. Published on 18 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.

SummaryPassive surface wave method is increasingly being applied to urban subsurface exploration due to its non-invasiveness, low cost, and high efficiency. However, its imaging quality is often influenced by limited data acquisition time and the heterogeneous distribution of seismic ambient fields in complex urban environments. To extract coherent surface wave signals for seismic imaging in such challenging setting, we developed a multi-stage urban ambient noise deep clustering framework based on a convolutional autoencoder and deep embedded clustering algorithm. The initial clustering characterizes the distribution patterns of urban noise sources, which informs a secondary, finer clustering to select noise sources optimized for urban seismic imaging. Real-world experiment on the urban train noise field demonstrates our urban noise cluster framework effectively identifies and elucidates the temporal evolution patterns of moving train sources. Compared to traditional data selection methods, our approach yields superior dispersion measurements and significantly attenuates artifacts from the fundamental mode. Furthermore, by employing mode-specific clustering, we successfully capture the refined first overtone, enhancing the accuracy and depth resolution of seismic imaging. This study presents a new perspective to analyzing and selecting complex noise sources, significantly advancing seismic imaging and monitoring in alignment with emerging Artificial Intelligence trends.

SummaryBoth short-term coseismic off-fault damage and long-term fault growth during interseismic periods have been suggested to contribute to the formation and evolution of fault damage zones. Most previous numerical models focus on simulating either off-fault damage in a single earthquake or off-fault plasticity in seismic cycles ignoring changes of elastic moduli. Here we developed a new method to simulate the damage evolution of fault zones and dynamic earthquake cycles together in a 2D anti-plane model. We assume fault slip is governed by the laboratory-derived rate-and-state friction law while the constitutive response of adjacent off-fault material is controlled by a simplified version of the Lyakhovsky-Ben-Zion continuum brittle damage model. This study aims to present this newly developed modeling framework which opens a window to simulate the co-evolution of earthquakes and fault damage zones. We also demonstrate one example application of the modeling framework. The example simulation generates coseismic velocity drop as evidenced by seismological observations and a long-term shallow slip deficit. In addition, the coseismic slip near the surface is smaller due to off-fault inelastic deformation and results in a larger coseismic slip deficit. Here we refer to off-fault damage as both rigidity reduction and inelastic deformation of the off-fault medium. We find off-fault damage in our example simulation mainly occurs during earthquakes and concentrates at shallow depths as a flower structure, in which a distributed damage area surrounds a localized, highly damaged inner core. With the experimentally based logarithmic healing law, coseismic off-fault rigidity reduction cannot heal fully and permanently accumulates over multiple seismic cycles. The fault zone width and rigidity eventually saturate at long cumulative slip, reaching a mature state without further change.

How is ventilation at various depth layers of the Atlantic connected and what role do changes in ocean circulation play? Researchers from Bremen, Kiel and Edinburgh have pursued this question and their findings have now been published in Nature Communications.

A computer model drawing on satellite and climate data could give scientists an early warning of coastal marsh decline.

Using the model, scientists detected a decline in underground plant biomass across much of Georgia’s coastal marshes between 2014 and 2023. Critically, this loss occurred even though the marsh grasses appeared green and thriving at the surface.

The findings, published last month in Proceedings of the National Academy of Sciences of the United States of America, could help land managers identify targets for restoration before more severe damage takes hold.

Roots of Concern

Marshes “are not only economically but culturally and recreationally important places for the people who both live along the coast and visit the coast.”

Marshes “are not only economically but culturally and recreationally important places for the people who both live along the coast and visit the coast,” said study coauthor Kyle Runion, a landscape ecologist at the University of Georgia. They help control flooding, sequester carbon, and provide space for hunting, fishing, and wildlife spotting.

But rapid sea level rise has threatened coastal marsh grasses, as higher waters and more frequent flooding inundate the soil and choke oxygen supply at the roots. In a healthy ecosystem, underground plant biomass staves off erosion and adds organic matter that eventually decomposes into more soil, boosting the marsh’s resilience to sea level rise, so declining root systems can be an early sign of trouble in marshlands.

Marshlands can appear healthy even as their roots are dying off, said Bernard Wood, a wetland ecologist at the Coastal Protection and Restoration Authority of Louisiana who was not involved in the study.

A trip into the marsh itself tells a different story, however. “You could just pick up this huge clump of grass with one hand, and it barely has anything holding it to the ground,” Wood said.

Sea level rise can threaten the roots of smooth cordgrass, even as the leafy part of the plant can appear healthy. The exposed roots of smooth cordgrass are seen here at a marsh edge along the Folly River in Georgia. Credit: Kyle Runion/Colorado State University BERM and Biomass

To understand how Georgia’s marshes are responding to changing conditions, researchers developed and tested the Belowground Ecosystem Resilience Model (BERM) in 2021. BERM draws from satellite and climate data to estimate the belowground biomass of Spartina alterniflora, or smooth cordgrass, in coastal areas.

In the 2021 study, the team collected information on environmental conditions in Georgia salt marshes from Landsat 8, Daymet climate summaries, and other publicly available datasets. They built a machine learning model that could predict belowground biomass and trained it on field data from four marsh sites. Researchers found that elevation, vapor pressure, and flooding frequency and depth were some of the most important variables in predicting root biomass.

How a salt marsh looks on the surface isn’t necessarily an indicator of how it’s truly faring.

In the new study, Runion and his colleagues applied the model to estimate changes in S. alterniflora root biomass over nearly 700 square kilometers of Georgia coast between 2014 and 2023.

During that time, belowground biomass decreased about 1% per year on average, the team found. About 72% of the salt marsh area saw declines in underground plant mass. At the same time, aboveground biomass—the visible part of the marsh grass—increased over most of the study area.

The disparity between biomass above and below could occur because aboveground biomass is less sensitive to flooding than root systems. Or the increase might be temporary, as flooding initially delivers nutrients but eventually drowns the plant. In either case, how a salt marsh looks on the surface isn’t necessarily an indicator of how it’s truly faring.

Tool for Conservation

Early-warning signs of marsh decline provided by the model could be crucial for conservation. “Once [marsh] loss occurs, that can be irreversible,” Runion said. “By getting a sign of deterioration before loss happens, that’s when we can intervene and much more easily do something about this.”

Mapping which areas of the marsh are most vulnerable could also combat the tendency to see marshes as either “doomed” or “not doomed” and target conservation efforts to the areas most in need, said Denise Reed, a coastal geomorphologist at the University of New Orleans who was not involved in the study. Though belowground biomass is declining on average, some areas of the coast are experiencing less change than others.

“There are some complex patterns going on—probably something that it would be great to understand a little bit better,” Reed said. But “this idea of being able to detect areas which are in worse condition versus areas that are in better condition from the soil’s perspective is really helpful.”

For now, BERM can predict belowground biomass only in Georgia marshes. Other regions have different plant species and flooding dynamics that could alter the relationships BERM relies on. But with additional calibration data from other salt marshes, the team could make the model more widely applicable, Runion said.

“We are looking to expand this sort of modeling framework to include different species along the Gulf and East Coast,” Runion said.

—Skyler Ware (@skylerdware), Science Writer

Citation: Ware, S. (2025), Machine learning model flags early, invisible signs of marsh decline, Eos, 106, https://doi.org/10.1029/2025EO250253. Published on 17 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.

Author(s): T. A. Shelkovenko, I. N. Tilikin, A. R. Mingaleev, V. M. Romanova, and S. A. Pikuz

The small-sized, low-voltage, and low-inductive KING generator (190–230 kA, 40 kV, 200–240 ns) was specially designed to work with X-pinches; however, it was unstable in its original design. In the present work, it is experimentally shown that an increase in the inductance of the output node of the …

[Phys. Rev. E 112, 015207] Published Thu Jul 17, 2025

Clear-cutting can make catastrophic floods 18 times more frequent with effects lasting more than 40 years, according to a new UBC study.

When a hurricane is in the forecast, the National Oceanic and Atmospheric Administration (NOAA) deploys its famed Hurricane Hunter team to gather data directly from the storm. The team uses specialized aircraft to fly into the hurricane and collect information about its intensity, structure, and movement, which is used to improve forecasts and warnings.

Satellites circling Earth have many different functions, including navigation, communications and Earth observation. About 8%–10% of all active satellites are military or "dual use" serving intelligence or reconnaissance functions as spy satellites.

Samples of extremely small crystal clots, each polished to the thickness of a human hair or thinner, have revealed information about the process triggering the major 2006 eruption of Alaska's Augustine Volcano.

Monitoring changes in water temperature and pressure at the seafloor can improve understanding of ocean circulation, climate, and natural hazards such as tsunamis. In recent years, scientists have begun gathering submarine measurements via an existing infrastructure network that spans millions of kilometers around the planet: the undersea fiber-optic telecommunications cables that provide us with amenities like Internet and phone service.

The landslide that occurred in Blatten in the canton of Valais at the end of May 2025 and the one in the village of Brienz in Graubünden in June 2023 remind us of the potential for landslide hazards in the Alps. Debris flows are one such hazard. These flows of water, sediment and rock fragments typically occur after heavy rainfall in steep terrain, and rapidly travel down a channel, potentially destroying everything in their path.

Source: Geophysical Research Letters

Monitoring changes in water temperature and pressure at the seafloor can improve understanding of ocean circulation, climate, and natural hazards such as tsunamis. In recent years, scientists have begun gathering submarine measurements via an existing infrastructure network that spans millions of kilometers around the planet: the undersea fiber-optic telecommunications cables that provide us with amenities like Internet and phone service.

Without interfering with their original purpose, the cables can be used as sensors to measure small variations in the light signals that run through them so that scientists can learn more about the sea. Liu et al. recently developed a new instrument, consisting of a receiver and a microwave intensity modulator placed at a shore station, that facilitates the approach.

Transcontinental fiber-optic cables are divided into subsections by repeaters, instruments positioned every 50 to 100 kilometers that boost information-carrying light signals so that they remain strong on the journey to their destination. At each repeater, an instrument called a fiber Bragg grating reflects a small amount of light back to the previous repeater to monitor the integrity of the cable.

By observing and timing these reflections, the new instrument measures the changes in the time it takes for the light to travel between repeaters. These changes convey information about how the surrounding water changes the shape of the cable, and the researchers used that information to infer properties such as daily and weekly water temperature and tide patterns. Most previous work using telecommunications cables for sensing efforts treated the entire cable as a single sensor, and work that did use them for distributed sensing required ultrastable lasers. This instrument allowed the team to do distributed sensing using more cost-effective nonstabilized lasers.

The research team included geophysicists, electronics engineers, and cable engineers. They tested the instrument over 77 days in summer 2024 on EllaLink, an operation cable with 82 subsections running between Portugal and Brazil. As temperatures and tides rose and fell, the transatlantic cable stretched and contracted, providing measurable changes in the light traveling within it.

The study showed that the existing network of submarine cables could be a valuable resource for monitoring ocean properties, enabling everything from early tsunami warnings to long-term climate studies. (Geophysical Research Letters, https://doi.org/10.1029/2024GL114414, 2025)

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

Citation: Sidik, S. M. (2025), A transatlantic communications cable does double duty, Eos, 106, https://doi.org/10.1029/2025EO250252. Published on 16 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.

Glaciers hold layers of history preserved in ice, offering unique insights into Earth's past that can also help us interpret the future. Trapped amidst the frozen water are microscopic deposits of dust, pollen, and even pollutants that scientists can use to examine environmental changes through time.

New research led by the University of Victoria (UVic) has illuminated a significant and previously unrecognized source of seismic hazard for the Yukon Territory of northwestern Canada.

Nor'easters are powerful and often destructive cyclonic storms that primarily impact the East Coast of North America. Some of these weather events have been so fierce that they earned the names "Perfect Storm," "Storm of the Century," and "Snowmaggedon."

SummaryGreen’s function expressions for seismic interferometry in acoustic and elastic media have been extensively studied and applied across a wide range of applications, including surface-wave tomography and generating virtual shot gathers. However, analogous expressions for coupled acoustic-elastic media systems remain absent, despite their importance for analysing cross-correlation wavefields from ocean-bottom nodal and seismometer recordings and other seismic problems in marine settings. To address this issue, we derive convolution- and correlation-type reciprocity relations for physically coupled acoustic-elastic media by combining Rayleigh’s and Rayleigh-Betti reciprocity theorems, incorporating the constitutive equations governing coupling at the acoustic-elastic interface, and applying time-reversal invariance principles for an arbitrary 3-D inhomogeneous, lossless medium. The derived relationships show that the acoustic and elastic Green’s functions between any two observation points in the medium can be expressed as integrals of cross-correlations of wavefield observations at those locations, generated by sources distributed over an arbitrarily shaped closed surface enclosing the two observation points. When the Earth’s free surface coincides with the enclosing surface, integral evaluation is required only over the remaining portion of the closed surface. If the sources are mutually uncorrelated ambient sources, the Green’s function representation simplifies to a direct cross-correlation of wavefield observations at the two points, generated by a specific ambient source distribution on the closed surface. However, in practical scenarios, the ideal source distribution necessary to retrieve Green’s functions is rarely realized, for example, due to non-uniform illumination. To address these challenges, we represent the ambient cross-correlations as self-consistent observations and introduce a cross-correlation modelling methodology that accounts for practical limitations in source distribution for coupled acoustic-elastic media scenarios. We illustrate the theory by modelling ambient cross-correlation wavefields for a deep-water scenario.