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Publication date: Available online 10 June 2026

Source: Advances in Space Research

Author(s): Jun Yang Li, Sean Wolfe, M. Reza Emami

Publication date: Available online 9 June 2026

Source: Advances in Space Research

Author(s): Qadeer Ahmed, Ankit Gupta, Anshul Singh, Aastha Rawat, Arti Bhardwaj, Puja Goel, A.K. Upadhayaya

Publication date: Available online 9 June 2026

Source: Advances in Space Research

Author(s): Khalid En-Nagre, Mourad Aqnouy, Ismail Bouizrou, Jamal Eddine Stitou El Messari, Gebiaw T. Ayele, Dmitry Kucher, Olga Kucher, Aqil Tariq, Hassan Alzahrani

Hilly and mountainous landscapes have a much greater ability to store carbon in the soil than previously thought, according to a new study co-led by scientists at the University of Oregon.

The temperature of rivers is something most people think about only if they plan to go swimming, kayaking or spend a day fishing. Few consider how it could potentially affect their electricity bill.

Nitrate pollution is a growing global environmental challenge due to the extensive use of fertilizer. A study published in Science, led by the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) with the Helmholtz Center for Environmental Research (UFZ), shows that both the amount of water moving through landscapes and how fast it moves play a key role in nitrogen pollution risk.

In a new study, Professor Shin Sugiyama of Hokkaido University and his team have directly confirmed for the first time that water from melting snow and ice, or meltwater, found at the surface of a glacier can drain to its base, causing glaciers in Antarctica to speed up and move toward the ocean.

New research shows surface melting across Antarctica is set to intensify and spread dramatically over the 21st century, with melt increasing 10-fold and the affected area growing by more than 10% by 2100 if global temperatures continue to rise.

Albert Einstein postulated in his 1905 theory of special relativity that the speed of light in a vacuum is constant. Ever since, that’s been one of the fundamental assumptions of physics.

Now Enbang Li, a physicist at the University of Wollongong in Australia, has challenged this idea by building a machine he says is capable of detecting changes in the speed of light as it crosses Earth’s surface. The findings suggest that light is, in fact, sped up by gravity, which could have implications for Earth science applications ranging from climate monitoring to mineral resource exploration.

An Old Conundrum

The idea that light is influenced by gravity is not new. Einstein’s ideas, which were further developed with his theory of general relativity in 1915, predicted massive objects in space would bend light with their gravitational grab. This theory was famously proven in 1919 when two independent teams measured starlight passing a solar eclipse at two different points on Earth’s surface and found the results matched Einstein’s predictions.

This bending of light’s path, according to general relativity, is achieved by a warping of the space-time fabric. Under this scenario, the speed of light remains constant—it just has to travel farther as it navigates the warped space-time around celestial bodies, so to a distant observer, it appears to have been slowed.

But what if light doesn’t navigate warped space-time and actually is slowed down or sped up by the gravity of large objects?

Li pointed out that Einstein himself was not always convinced the speed of light was constant. In 1911, he wrote a paper postulating that light speed changed depending on the gravity of objects it passed by. However, “when he published his general theory,” said Li, “he just abandoned this model.”

If the movement of light can be affected by gravity, Li reasoned, it might be possible to detect variations in its speed on a local level—such as an elevator shaft in a building on the campus of the University of Wollongong.

Raising the Big Issues

Gravity on Earth varies locally, depending on altitude, underground density, and topography. Gravity at the top of a tall building, for example, is measurably weaker than it is at the bottom.

With these variations in mind, Li installed an experiment in an elevator. It consisted of a coil of fiber-optic cable that if stretched out in one direction, would be 10 kilometers (6.2 miles) long. Laser beams were fired through the cables and then reflected back, thus traveling 20 kilometers (12.4 miles) before reaching an ultrafast photodetector. An oscilloscope measured the time it took for the beam to travel that distance. The experiment was run at the top of the shaft and at the bottom.

The biggest challenge, Li said, was filtering out all the surrounding environmental “noise,” such as changing temperature and humidity, electromagnetic disturbance, and building vibrations. Li designed a temperature control system, and the experiment was sealed in an enclosure with electromagnetic shielding to isolate air flows. Li ran the experiment and found light moved minutely faster at the bottom of the shaft than at the top.

Gravity Sensing on the Go

Next, Li took his research a step further by building a small, portable machine he claims can detect changes in the speed of light as it nears more gravitationally dense objects.

In this second experiment, Li positioned a moveable 72-kilogram (159-pound) weight near the machine. Light, he found, moved faster when the weight was near the machine than when it was farther away.

The results, which were published in Scientific Reports, are consistent with the variable speed of light model Einstein proposed in 1911, although Li’s preliminary results are much larger than that model predicts.

If proven, the findings would present a fundamental challenge to our understanding of both general and special relativity.

In the world of Earth sciences, they could lead to greatly improved gravity-sensing technologies. Because of their sensitivity to changes in mass, gravity sensors are used to map the seafloor and to locate underground mineral reserves. Gravity sensing can also improve our understanding of Earth’s climate as variations in the gravity field can be linked to factors like changes in ice mass and shifts in groundwater.

Currently, gravimeters are vulnerable to vibrations and movement, whereas Li’s machine, which has no moving parts, could even be used on board a plane or submarine.

“A Striking Claim”

Chris Stevens, a numerical relativist with the University of Canterbury in New Zealand, called the work “intriguing and ambitious.” While Stevens, who was not involved in the research, said that Li’s work is “well founded,” he noted that any observable effects of gravity on light on Earth would be “extraordinarily small” and therefore these results must be treated with caution.

“In my own research on observable gravitational phenomena,” he explained, “I usually require a few black holes colliding somewhere in the universe. Separating genuine gravitational signatures from environmental and instrumental noise will therefore be exceptionally demanding.”

“The work is exciting because it pushes precision photonic measurement techniques into a regime where relativistic effects may become practically useful for geophysics and sensing applications.”

Stevens said the implications of Li’s research, if validated, would be far-reaching. “The work is exciting because it pushes precision photonic measurement techniques into a regime where relativistic effects may become practically useful for geophysics and sensing applications.”

John Norton, an historian of physics at the University of Pittsburgh who was also not involved in the research, called the findings a “striking claim.” He was, however, skeptical of them, saying “if there is a coupling between light and gravity of magnitude greater than general relativity predicts, it is hard to see how the 1919 eclipse test and later studies of gravitational lensing would not have found it.”

Li acknowledged there is a long way to go before his device finds everyday use. Disentangling the intricacies of space and time, he said, is a vast challenge. “In physics, people still say gravity is a mystery. Light is another mystery. So if you put these two mysteries together, that’s going to be a giant mystery.”

—Bill Morris, Science Writer

Citation: Morris, B. (2026), How Einstein’s lost theory could help us find minerals, Eos, 107, https://doi.org/10.1029/2026EO260189. Published on 12 June 2026. Text © 2026. 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): Pooja Dalal and Ram Prasad Prajapati

The Jeans instability in an unmagnetized, collisionless self-gravitating plasma characterized by a kappa or Lorentzian velocity distribution is investigated in the framework of kinetic and fluid approaches. We have examined the role of suprathermality on the instability threshold wave number and gro…

[Phys. Rev. E 113, 065208] Published Fri Jun 12, 2026

SummaryThis study leverages a new, improved and densified GNSS velocity field of the western Aegean region to quantify slip rates, strain localisation, and interseismic loading within the upper plate of the Hellenic subduction zone, including the deformation systems associated with the subduction–collision transition around Cephalonia, the Hellenic forearc extension, and the southwestern termination of the North Anatolian Fault system. We examine several active tectonic domains, comprising four extensional regions (Corinth–Patras Rift, Evia Gulf, Argolic Gulf, southwestern Peloponnese) and three strike-slip systems (Cephalonia Transform Fault, Katouna–Stamna Fault System, Movri Fault Zone). Across the Corinth Rift, NS extension increases westward from ≈ 7 to ≈ 15 mm.yr$^{\hspace{1.0pt}\text{--}1}$, of which up to ≈ 6 mm.yr$^{\hspace{1.0pt}\text{--}1}$ is accommodated offshore. Velocity profiles indicate combined elastic loading and aseismic creep on a limited number of crustal-scale faults. The Evia–Boeotia sector undergoes NS extension at up to 8 mm.yr$^{\hspace{1.0pt}\text{--}1}$, but deformation is distributed across multiple structures, each accommodating creep or elastic loading at rates <2 mm.yr$^{\hspace{1.0pt}\text{--}1}$. In the southern Peloponnese, diffuse EW extension of up to 6 mm.yr$^{\hspace{1.0pt}\text{--}1}$ occurs alongside 1–2 mm.yr$^{\hspace{1.0pt}\text{--}1}$ of NS extension in the central Peloponnese. A portion of this EW deformation may be accumulating interseismically as elastic strain on prominent structures, such as the Sparti and East Messenia faults. No measurable strain is detected across the Argolic Gulf, suggesting substantially lower present-day loading rates on the Astros Fault than previously inferred. Strike-slip systems display contrasting behaviours. The Katouna segment accommodates transtensional left-lateral creep of ≈ 13 mm.yr$^{\hspace{1.0pt}\text{--}1}$ within a zone <6 km wide, whereas slip decreases to ≈ 8 mm.yr$^{\hspace{1.0pt}\text{--}1}$ on the Stamna segment, consistent with strain transfer through the Trichonida pull-apart basin and the Nafpaktia diffuse shear zone. In contrast, the Movri Fault appears locked down to at least 10 km depth, accumulating ≈ 4 mm.yr$^{\hspace{1.0pt}\text{--}1}$ of right-lateral strain. Onshore velocities near the Cephalonia Transform Fault indicate an onshore half-rate of elastic loading of ≈ 8 mm.yr$^{\hspace{1.0pt}\text{--}1}$, suggesting that the full transpressional right-lateral motion (≈ 16 mm.yr$^{\hspace{1.0pt}\text{--}1}$) accumulates interseismically, highlighting considerable seismic hazard potential.

SummaryDistributed Acoustic Sensing (DAS) data often contain various types of noise, including random noise, coherent noise (e.g., coupling or linear noise), and common mode noise, which significantly degrade seismic signal quality. Conventional denoising methods struggle to effectively suppress diverse noise components while preserving important seismic signals. To address this issue, we propose a denoising self-supervised cascade network (DAS-DSCnet), a multi-stage neural network designed to progressively denoise DAS data without requiring external labels or synthetic training data generation. The network consists of three stages: Stage 1 targets random noise using a Noise2Noise-based approach; Stage 2 suppresses dataset-specific coherent noise using a denoising convolutional neural network (DnCNN)-based network trained with internally extracted noise patches; and Stage 3 predicts and removes common mode noise through trace shuffling and a Noise2Noise-based model. Training data for each stage are generated directly from the input DAS data by exploiting the data’s inherent characteristics, enabling efficient learning that reflects field-specific noise features. The model was evaluated using two distinct field DAS datasets with different noise patterns. The results demonstrate that DAS-DSCnet achieves superior noise suppression compared to conventional approaches, enhancing signal continuity while minimizing leakage. The denoising performance remains stable across different stacking configurations and hyperparameters, confirming the model’s robustness. Therefore, DAS-DSCnet offers a scalable and practical framework for improving seismic data quality in DAS applications, demonstrating the potential for fully automated, data-driven denoising in large-scale seismic monitoring.

SUMMARYWe present a comprehensive dataset of 920 coordinates and 509 velocities for geodetic points in central Greece and the Peloponnese, an area characterised by intense tectonic deformation. The points, with observation periods within the 1990–2024 range, are organised into three categories: permanent stations, triangulation pillars, and markers. The latter two categories are subdivided according to whether or not they feature self-centring. Most of the triangulation pillars belong to the Greek national network originally surveyed in the 1960s–70s. The GNSS data were processed using the GIPSY 6.4 software. To assess the secular velocities, we corrected for co-seismic and post-seismic displacements using earthquake parameters constrained by the time series of the permanent stations. Self-centring systems improve precision, reducing the average horizontal coordinate residual variability from 6.15 to 4.45 mm. The velocity uncertainties stabilise below 0.15 mm yr−1 when the time series exceed twenty years. Points with self-centring achieve 0.2 mm yr−1 accuracy after twelve years of data, compared to twenty years for those without self-centring. After twenty-five years, campaign points observed eight to ten times match the precision of permanent stations. The velocities at the campaign points further validate the HELVEL model previously developed using permanent stations only. We calculate a seven-parameter transformation from the original coordinates of 424 triangulation pillars to their GNSS-based ITRF2020 coordinates at epoch 2020.0. The lowest mean scatter after the transformation is 0.134 m when 1965 is used as the mean epoch for the triangulation data. We then apply this transformation to all 9,729 pillars of the study area. At the 424 resurveyed pillars, the GNSS ellipsoidal heights agree with the sum of the levelled heights and the official HG2023 geoid heights to within 0.184 m root-mean-square. Our dataset is entirely referenced to ITRF2020 at epoch 2020.0, which enables interoperability with previous and future geodetic studies. Dense campaign point arrays are critical for resolving the strain distribution at the scale of individual active faults, beyond the reach of arrays of permanent stations alone.

AbstractMantle viscosity remains one of the largest outstanding uncertainties in global geodynamics. Time-dependent mantle circulation models that assimilate tectonic histories (MCMs) provide a way to test viscosity by assessing their present-day predictions against observations. This approach allows for the influence of viscosity on mantle density structure to be accounted for, which is not possible using instantaneous modelling approaches. Here we present the first systematic test of lower mantle viscosity against dynamic topography, the geoid, and seismic heterogeneity using high-resolution MCMs. Model density structure depends strongly on the assumed viscosity profile, which in turn controls the fit to seismic heterogeneity. The fit to dynamic topography and the geoid is further influenced by the instantaneous transmission of stresses to the surface. These two effects can either reinforce or counteract each other at different depths, which must be considered when attempting to match dynamic topography and geoid amplitudes. MCMs typically overestimate dynamic topography amplitudes. We find that it is possible to reduce these amplitudes by lowering viscosity in the upper lower mantle (≈660-2000 km), though this comes at the expense of a reduced fit to the geoid and/or seismic heterogeneity. Our preferred viscosity profile provides an excellent fit to observed geoid amplitudes and the seismic heterogeneity of S40RTS. We also tested an alternate tectonic reconstruction with tomography-based refinements around the Pacific which improved the correlation with the observed geoid by ≈20%. Our results show that MCMs can now reach a level of resolution and realism sufficient for comparison to multiple independent data sets, opening the door to systematic assessment of uncertain parameters which govern convection in the mantle.

SUMMARYThe excitation and propagation of multiple wave types, including seismic waves, ocean acoustic waves, and tsunamis triggered by earthquakes within the oceanic wavefield, constitute a problem of substantial scientific and practical challenge. This phenomenon involves complex interactions of waves within a fluid-solid coupled system, which is critical for both fundamental geophysical understanding and enhancing hazard assessment. While several numerical methods have been developed to simulate the full wavefield, few studies have systematically explored the crucial influence of complex seafloor topography on coupled wave dynamics. This study introduces a novel earthquake-tsunami coupling simulation method within a 2-D spectral-element method (SEM) framework, leveraging its flexibility to handle complex geometries and accuracy for long-range wave propagation. To validate the accuracy of the simulated seismic waves, ocean acoustic waves, and tsunamis, we quantitatively evaluate the permanent seafloor displacement, yielding a high correlation coefficient of 0.997 and a negligible error of 5 × 10−3 compared with the analytical solution. The mean relative error of the calculated tsunami phase velocities of the proposed method with those from the propagator matrix method is only 0.12%. Furthermore, we establish two distinct numerical models—one incorporating irregular bathymetry and another with an idealized flat bathymetry—to systematically investigate the effects of bathymetry on the oceanic wavefield. Our results demonstrate that the irregular bathymetry significantly influences the propagation characteristics of both seismic waves and tsunamis, altering wave amplitudes, travel times, and spatial patterns. We further decompose the contributions of seawater and seafloor geometry, highlighting their respective roles in shaping the overall wavefield. Additionally, we examine the influence of varying earthquake source locations on wave propagation paths, emphasizing the importance of accurately modelling bathymetry for offshore seismic events. Overall, our proposed 2-D earthquake-tsunami coupling simulation framework provides a powerful tool for comprehensively understanding the oceanic wavefield under gravity and offers significant potential for improved earthquake and tsunami hazard assessment, particularly when combined with seismological and oceanographic observations.

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

The key word here is could. Experts including Ken Graham, the director of NOAA’s National Weather Service, all emphasize that no two El Niños are alike.

“Each one is unique with its own imprint on our weather,” Graham said in a NOAA press release. However, scientists have learned a few things from watching the ways that this warm phase of a natural climate cycle over the tropical Pacific has affected our weather patterns in the past.

“Advanced monitoring and an improved understanding of El Niño patterns allow the NWS to better predict and better prepare the public and our core partners for what is to come,” Graham said.

 Related

•  El Nino forms, expected to strengthen, say NOAA forecasters
•  Our Warming Waters Press Briefing
•  NOAA Forecasts a Below Average Hurricane Season
 

This morning, NOAA released an El Niño Advisory, announcing that the climate phenomenon (the warm phase of the El Niño–Southern Oscillation) has officially arrived in the tropical Pacific. The agency forecasts a 63% chance of a “very strong” El Niño from November 2026 to January 2027 that “would rank among the largest El Niño events in the historical record.”

NOAA defines a “very strong” El Niño as when the Pacific’s surface waters are more than 2°C warmer than average. The agency doesn’t use the phrase “Super El Niño,” but there have only been three such “super” or “very strong” El Niño events since 1980. The last one was in 2015.

What does this mean for climate, for humans, and marine species? Here’s a roundup of some potential forecasted effects—some good, some bad—of the weather pattern that’s been making headlines over the past few months.

1. More rain and snow in the southern U.S.

In a typical year, a warm pool of water in the equatorial Pacific would be transported westward—away from the western coast of the Americas—by trade winds. But during an El Niño event, those trade winds weaken, and the warm pool of water extends east, explained Ariel Cohen, the meteorologist in charge of the National Weather Service’s Los Angeles and Oxnard Office in a press briefing at the Aquarium of the Pacific in Long Beach, Calif.

This warm water “causes jet energy in the atmosphere to bring disturbed weather southward across the southern United States, which can bring wetter than normal conditions to our area with drier conditions farther to the north,” Cohen said.

The southward shift of the storm track could also lead to drier conditions over the northern Rockies and as far east as the Ohio and Tennessee Valleys.

2. More shark and whale sightings off the Southern California coast

In the past, strong El Niños have led to decreased amounts of plankton in the Pacific, particularly the open ocean, forcing species that rely on plankton (and the species that rely on the species that rely on plankton, and so forth) to widen their net when searching for food.

“[Plankton] is important because that’s the base of the food web,” explained Andrew Leising, a research oceanographer at NOAA, at the Aquarium of the Pacific. “Marine mammals and other migratory species end up being closer to shore, because they’re going to where their food is.”

Whales in particular rely on the upwelling of cold water to bring them krill to eat. As they are driven nearer to the coast in search of food, they also grow more likely to become entangled in fishing nets.

3. A milder Atlantic hurricane season

Warm water is a key ingredient in a hurricane, so it might seem, at first thought, that the Pacific’s unusually warm waters might augur a more extreme hurricane season. But another effect of El Niño is that it strengthens vertical wind shear over the Atlantic. When winds are too strong, they can tear a storm apart before it picks up the momentum to become a hurricane.

“Wind shear is good for us, bad for the hurricanes,” Phil Klotzbach, a hurricane forecaster at Colorado State University and lead author of the university’s 2026 Atlantic Hurricane Forecast, told Eos.

NOAA’s 2026 Atlantic Hurricane Forecast suggests that the 2026 season has a 55% chance of being below normal, and will likely include 8 to 14 named storms with winds of at least 39 miles per hour.

4. Fewer squid along the California coast

Past El Niño events have shown that warmer Pacific waters can increase the likelihood of harmful algal blooms. Among other effects, these blooms can lead to a lower abundance, and a northward shift, of market squid. Market squid and Dungeness crab bring the most volume and value to California’s commercial fisheries.

In 2014, a large mass of hot water in the Pacific known as the Blob was followed up by an El Niño event. That year, “we had several closures of crab and shellfish fisheries due to harmful algal blooms,” Leising said.

However, Leising also explained that the warm patch of water in the Pacific this year is much smaller and farther from shore than the Blob was in 2014. So, though we may see effect similar those in 2014, they’re likely to be less extreme.

In addition, the same conditions driving sharks and whales toward the coast could also drive tuna toward the coast, leading to increased opportunities for that fishery.

5. More high-tide flooding on U.S. coasts

With El Niño shifting the Pacific jet stream south of its usual position, sea levels along the U.S. West Coast may rise, exacerbating the existing sea level rise linked to climate change. On the East Coast, the jet stream shift can lead to more storm surges, which combine with higher-than-typical precipitation levels.

“It usually ends up being a double whammy,” said NOAA oceanographer and high tide flooding expert William Sweet, in a NOAA news story. “The first punch is decades of sea level rise, which has waters close to the brim in many coastal communities. And now with this second punch—a strong El Niño—coastal communities face more frequent, deeper and widespread high tide flooding along both the West and East Coasts.”

6. A bad year for sea lions

El Niño events can have harmful effects on sea lions. Algal blooms can lead to severe illness, or even death, for the pinnipeds. Algal blooms can also kill off fish and cephalopod species (such as market squid) that sea lions rely on for food. During past El Niño events, California sea lions have also experienced lower rates of reproduction and produced smaller pups, Leising said.

“California sea lions are indicator species, meaning they will be one of the first species which may show signs of domoic acid toxicity, respond to changes in their ecosystem, and signal to the public how our oceans and ecosystem are doing,” said Brett Long, vice president of animal care at the Aquarium of the Pacific.

—Emily Gardner (@emfurd.bsky.social), Associate Editor

These updates are made possible through information from the scientific community. Do you have a story about science or scientists? Send us a tip at eos@agu.org. Text © 2026. 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.

Planetary heating is intensifying and key climate indicators are deteriorating, top scientists said Thursday, warning that funding decisions affecting Earth observation systems in the United States and other countries threaten efforts to track global warming.

In 2023, Cyclone Gabrielle triggered an estimated 800,000 landslides across the North Island, making it one of the most extreme landslide events ever recorded. New research by Te Whare Wānanga o Waitaha | University of Canterbury (UC) and Earth Sciences New Zealand suggests that under a warmer climate, future storms similar to Cyclone Gabrielle could be even more extreme, triggering tens of thousands more landslides across parts of the North Island and highlighting the need for targeted planning in vulnerable areas.

A new study finds that burning 500,000 acres (202,000 hectares) of California conifer forests each year with prescribed fire could cut deadly pollution from wildfire smoke by roughly 10% over a decade.

In a new paper published in Science, leading scientists and climate policy experts show that 15% of current global warming (0.3°C) from human emissions stems from pollutants that fall outside most existing climate policy frameworks. Most of these overlooked pollutants are called "indirect greenhouse gases" and include carbon monoxide, non-methane volatile organic compounds, nitrogen oxides and molecular hydrogen.