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SummaryThermal conductivity anisotropy influences heat flow in the crust, yet predicting it from rock fabric remains difficult because the effective conductivity of a polycrystalline rock depends not only on mineral thermal properties and crystallographic preferred orientation, but also on grain shape, phase distribution and grain-scale interactions. Here we extend an asymptotic expansion homogenization–finite element (AEH–FE) framework for polycrystals to anisotropic heat conduction in rocks. Single-crystal conductivity tensors are rotated according to measured crystallographic orientations and assigned throughout the microstructure, and 2-D electron backscatter diffraction (EBSD) maps are analysed as representative sections extruded normal to the section. The method yields both the homogenized conductivity tensor and microscale heat-flux fields for prescribed macroscopic temperature gradients. To characterize section-based anisotropy, we define a coordinate-independent in-plane measure from the extrema of directional conductivity. We apply the method to a simple natural microstructure comprising a single mica grain in a quartz matrix and to three natural phyllosilicate-rich rocks representing planar foliation, transitional crenulation cleavage, and fully developed crenulation cleavage. Progressive fabric reorganization reduces in-plane anisotropy (max/min thermal conductivity) from A2D = 2.77 for planar foliation to A2D = 1.22 for fully developed crenulation cleavage. The transitional fabric remains substantially anisotropic (A2D = 2.26) despite similar diagonal tensor components because a large off-diagonal term rotates the principal conductivity directions. Comparisons with Voigt, Reuss, Voigt–Reuss–Hill and geometric-mean estimates show that classical averages capture broad trends but can misrepresent both anisotropy magnitude and principal directions when microstructures are strongly textured or spatially organized. These results demonstrate that EBSD-resolved multiscale homogenization provides a physically grounded route from rock fabric to effective thermal conductivity tensors and microscale heat-flow patterns relevant to geophysical models of anisotropic crustal heat transport.

SummaryReflectivity estimation aims to enhance the resolution of seismic data, providing crucial support for the detailed inversion of reservoir parameters. We propose a method that combines supervised pre-training with synthetic data and physics-guided fine-tuning in field data to estimate reasonable reflectivity from seismic data. Initially, a U-shaped network is pre-trained by supervised learning on a large amount of synthetic seismic data. Subsequently, multiple geophysically meaningful constraints including structure-oriented smoothness, reflectivity sparsity, and data reconstruction, are introduced to formulate a self-supervised or unsupervised learning mechanism to fine-tune the pre-trained model so that it is better adapted to field data for obtaining more reasonable reflectivity. The pre-trained model provides an initial reflectivity that aligns with fundamental structural features. Based on the initial estimate, the model is further optimized through physics-guided fine-tuning to obtain a more reasonable reflectivity estimation that better reflects the characteristics of the field data and geophysical priors. Furthermore, the well-log-based correlation evaluation metric is applied to automatically and adaptively determine the early-stopping point of the fine-tuning process where favorable results are achieved. Experiments on synthetic and field seismic data confirm that the proposed method yields reasonable and high-resolution reflectivity estimation.

How much ice is stored in the world's glaciers? And where exactly is it located? A new study led by Ca' Foscari University of Venice, in collaboration with the Institute of Polar Sciences of the National Research Council of Italy (CNR-ISP), provides an updated global map of glacier ice volume.

The initiation of rain in clouds without ice remains one of the largest unsolved mysteries in atmospheric science.

Zooming from her office, Michigan State University researcher Kelly Kapsar showed satellite images from across the United States. In some, different colors revealed the precise heights of the forested ridges in the Sierra Nevada or the craggy peaks of the Rockies and the valleys between them. Others showed the pine flatwoods of southern Florida or the smooth, rolling grasslands of the Kansas prairie.

Source: AGU Advances

Within our solar system, Uranus is a geometric oddball. Its spin axis tilts more than 90° from its orbit, so it essentially rolls on its side through space. In contrast, Earth and other planets tilt only moderately or not at all. What’s more, the ice giant’s magnetic field is strangely offset and tilted another 60°.

These extreme asymmetries mean that the interaction between Uranus’s magnetic field and the solar wind—charged particles constantly streaming out from the Sun in all directions—is also quirky. At Earth and other planets, the boundary where the solar wind slams into the planetary magnetic field and abruptly slows to form a turbulent shock wave, known as the bow shock, is relatively stable. But at Uranus, the bow shock is highly dynamic, changing shape and size throughout each Uranian day, like the expansion and contraction of breathing lungs.

However, the precise extent and underlying drivers of the Uranian bow shock’s “breathing” have so far been unclear. Now, using advanced computer simulations and data from NASA’s Voyager 2 spacecraft, Cao et al. have quantified the specifics of these daily, repeating changes.

The researchers used a three-dimensional multifluid magnetohydrodynamic model, a tool they recently developed to explore how planets’ magnetospheres interact with the solar wind. For these simulations, they incorporated observations made by Voyager 2 in 1986 when it flew by Uranus. They ran the model under the condition of Uranus’s equinox, the part of its 84-Earth-year orbit during which the Sun is directly over the equator and the bow shock’s expansion and contraction are strongest.

The simulations revealed precisely how the bow shock of Uranus evolves in size and shape over the course of one full day. To isolate the role of planetary rotation, the researchers ran some simulations under conditions of steady, unchanging solar wind. The regular, daily pattern persisted, suggesting that rotation-driven daily reconfiguration of the magnetic field geometry, rather than solar wind changes, is primarily responsible for the breathing.

In contrast, at Earth, solar wind changes are the main driver of variability in the bow shock, with only small daily variations arising from the slight angle between Earth’s spin axis and its magnetic field.

These findings could help inform future space missions to Uranus and could aid in understanding the bow shocks of the numerous ice giant exoplanets detected throughout the galaxy. (AGU Advances, https://doi.org/10.1029/2026AV002307, 2026)

—Sarah Stanley, Science Writer

Citation: Stanley, S. (2026), Getting to know Uranus’s “breathing” bow shock, Eos, 107, https://doi.org/10.1029/2026EO260255. Published on 7 August 2026. 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.

When the Tajogaite volcano erupted on the Spanish island of La Palma in 2021, it changed the local landscape almost overnight. What started as a small fissure spewing gas and volcanic ash soon grew into a massive volcanic cone. Lava flows destroyed hundreds of homes and basic infrastructure such as roads and water pipes, but they also created a natural laboratory for scientists.

Tajogaite erupted in September 2021. Credit: Eduardo Robaina/Wikimedia Commons, CC BY-SA 3.0

As the lava cooled and slowed on the surface, molten rock continued to flow through channels under the surface. Once the eruption ceased and the lava drained out, the empty tubes remained, forming a tunnel network. Between 12 and 24 months after the eruption, a team of researchers went onto the still cooling lava tubes of La Palma to study how life gets its first foothold and colonizes these newly created environments.

Numerous studies have investigated how life takes hold on new surface lava, and mature microbial communities in lava tubes have also been studied in the past, but this is the first time the colonization process has been studied underground from the very beginning, the researchers said. It could help researchers learn more not just about terrestrial lava tubes but about those on Mars or the Moon.

This photo was taken from the interior of a lava tube formed during the eruption of Tajogaite, including white mineral deposits coating the walls. Credit: Nicasio Jiménez

“This is a unique opportunity; we are studying nature’s blank pages,” said Ana Miller, a geomicrobiologist at the Institute of Natural Resources and Agrobiology of Seville in Spain who led the study published in Environmental Microbiome.

The tubes formed by the Tajogaite eruption were sometimes tall enough for a person to walk upright through them. But the temperatures could be uncomfortably hot, even after toxic gases had dissipated and initial temperatures cooled from upward of 800°C (1472°F). In some sampling sites, air temperatures hovered at a blow-dryer hot 60°C (140°F), while rock surfaces reached 90°C (194°F).

Yet even in such inhospitable conditions, the researchers found adventurous microorganisms already dwelling in the caves and, in some cases, altering the rock.

The Lucky Few

Though these passages are underground, they aren’t entirely sealed from the outside world. In some locations, sections of the tubes collapsed, or bubbling lava created holes in the roofs of the lava flows, known as skylights. Cracks in the rock also allow rainwater to enter the caves.

These openings are entry points for the first colonizers, which are carried by wind and rain or transported by living collaborators, such as birds, rodents, insects, and even worms. The microorganisms are accompanied by a nutrient cache of decaying vegetation, feathers, and guano.

On the basis of previous studies, the researchers thought that only the highly specialized microorganisms that can extract energy from chemical reactions with minerals—known as chemolithotrophs—could survive these early stages. The results at Tajogaite, however, show this isn’t entirely true.

Researchers explore the interior of a lava tube known as “Tubo Rojo,” which formed during the Tajogaite eruption. Credit: Nicasio Jiménez

The team collected scrapings from the cave floors and walls, combining traditional laboratory cultures with advanced genetic sequencing, and found that the microbial communities were not uniform. If light or organic matter was available, opportunistic organisms prevailed, with random luck playing a role in which species made it into the caves—a process called stochastic seeding. However, the harsh interior conditions of the lava tubes decided which microorganisms survived over the long term, favoring highly specialized species adapted to extreme environments. Deep within the caves, where there is no organic input, no light, and very little humidity, only these specialists survived.

The rapidly changing environment in the caves likely also influences the colonization process. “In a newly formed tube, the rock is still cooling down,” said Francesco Sauro, a geologist at the University of Padua in Italy who wasn’t involved with the new study. “You have cracking of the lava linings on the walls, collapses, and a lot of secondary mineralization that is metastable—meaning it exists only at that specific condition of temperature and humidity.”

This close-up shot shows some of the details of the lava formations within Tubo Rojo. Credit: Octavio Fernández

In contrast to mature lava tubes that formed thousands of years ago, which present stable conditions and mature microbial communities that are in equilibrium with the environment, young ones like those in La Palma evolve rapidly. “If you go back to Tajogaite or Iceland after 2, 5, or 10 years,” Sauro said, “the community will have changed for sure.”

Leaving Their Mark

“It isn’t just a case of microbes arriving, depositing on the walls, and surviving. To survive, they must interact with the volcanic substrate.”

Using electron microscopy, the team also found that the organisms are already dissolving and creating new minerals out of the rock.

“The microscopy helps us see if the microorganisms are associated with the mineral structures,” Miller said. “It isn’t just a case of microbes arriving, depositing on the walls, and surviving. To survive, they must interact with the volcanic substrate. That activity confirms we have a community developing.”

The research team poses for a photo with their protective gear before venturing into a lava tube. Credit: Ana Miller

The researchers found that the microbes were already forming biofilms—mat-like structures that help them attach to rock. Biofilms also retain humidity, helping the microbes capture the little moisture available, along with dissolved nutrients. Subtle alterations like biofilm formation represent the very first steps of a process that, over millions of years, will eventually break the rock down to form soil, Miller said.

Mars Underground

Lava tubes like the ones created in La Palma are common features in volcanic environments both on and off Earth. These subsurface structures are considered a possible last redoubt for life on Mars, if it ever existed.

Lava tubes could provide a stable sanctuary, shielded from the freezing, radiation-bombarded, and chemically aggressive surface environment of the Red Planet. Understanding how life takes hold in newly created terrestrial tubes, like those in La Palma, could help inform how the same processes could occur on Mars.

Researchers believe that these features captured by the High Resolution Stereo Camera aboard the European Space Agency’s Mars Express are lava tubes. Credit: ESA/DLR/FU Berlin (G. Neukum), CC BY-SA 3.0 IGO

One of the main controversies surrounding the idea of life in Martian lava tubes, however, is that most of the tubes that exist today formed after the planetary shift that ended habitable surface conditions on Mars roughly 3.8 billion years ago. This timing casts doubt on whether life ever had the chance to colonize them, Sauro said.

However, the larger picture is that lava tubes never stopped forming on Mars, at least throughout the first half of its history. “They were forming 4 billion years ago, and then through up to 2 billion years ago while volcanism was still active,” Sauro said.

In this way, Martian lava tubes could provide temporary “houses” that life could colonize one after the other, Sauro said. The fact that on Earth this colonization is extremely quick—not taking decades, but happening as soon as the temperature drops below a certain threshold—suggests that even young Martian lava tubes could have been rapidly colonized by surviving bacteria, Sauro said. “As soon as the lava tube is below a certain temperature and there is availability of liquid water, then it’s done.”

—Javier Barbuzano (@javibar.bsky.social), Science Writer

Citation: Barbuzano, J. (2026), A rare look at how life first colonizes cooling lava tubes, Eos, 107, https://doi.org/10.1029/2026EO260253. Published on 7 August 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): Pedro F. Gil, Weiping Li, Julianne Stratton, Alan A. Kaptanoglu, and Eve V. Stenson

Finding feasible coils for stellarator fusion devices is a critical challenge of realizing this concept for future power plants. Current design efforts struggle to navigate the highly nonconvex optimization landscape, spend considerable resources scanning the parameter space, and may produce subopti…

[Phys. Rev. E 114, 025202] Published Fri Aug 07, 2026

Throughout the 18th and 19th centuries, Europe's cartographers traded on their reputation for accuracy and detail at a time of huge societal change. But as demand grew for increasingly detailed maps of the world to support industrialization at home and colonization overseas, they didn't always get it right.

Stanford researchers have shown that instruments primarily used to understand earthquakes can capture key details about hurricanes, helping meteorologists better predict how storms will evolve and intensify.

The Arctic is warming at an accelerating pace. As permafrost thaws across vast areas and wildfires become more frequent, large amounts of methane (CH4) are being released. Together, these changes are reshaping the region's greenhouse gas emissions and further intensifying climate change.

The images of the major forest fires in Spain and France, with fire clouds near Bordeaux, have shocked many people. There have been numerous reports of the formation of a pyrocumulonimbus cloud—a fire-driven thundercloud—and the possible transport of smoke particles to Central Europe.

During the most recent ice age, much of North America disappeared beneath ice sheets several kilometers thick. These frozen giants covered most of present-day Canada and parts of the northern United States, while smaller ones spread across northern Europe.

Typhoons pose significant threats, with sudden, dangerous waves that endanger ships, offshore platforms and coastal infrastructure in the northwest Pacific Ocean. Current typhoon forecasting methods sometimes underestimate the largest waves during typhoons, but researchers in China have designed a new model that may offer improvements. Their new study, published in Ocean Engineering, describes how the model combines physics guidance with data-driven learning to improve typhoon forecasting.

Source: AGU Advances

Deep inside super-Earths—rocky planets with a mass anywhere between 1 and 10 times that of Earth—high pressure can cause familiar minerals to take forms that are rarely seen on Earth. Understanding more about the temperature and pressure conditions under which these phases are reached could help researchers learn more about how planets evolve.

One such mineral is magnesium orthosilicate, or Mg2SiO4, one of the major building blocks of rocky planets. As pressure increases deep inside a planet, the atoms in this mineral rearrange into different crystal structures. One of these high-pressure forms is called the spinel phase, which is found in Earth’s mantle. At even higher pressures, this phase breaks down into two different minerals: bridgmanite, the most abundant mineral phase in Earth, and ferropericlase, a magnesium-rich oxide. However, under the far more extreme pressures expected inside massive rocky planets known as super-Earths, Mg2SiO4 becomes stable again in an entirely new crystal structure called post-post-spinel. Scientists predict that this ultrahigh-pressure phase of Mg2SiO4 is one of the dominant minerals in the deep mantles of super-Earths, making its melting behavior important for understanding how these planets form and evolve.

Re-creating the high temperatures and extraordinary pressures inside massive rocky planets is challenging in the lab, so Zheng et al. took a computational approach. The team used a technique called thermodynamic integration to study the melting curve of post-post-spinel Mg2SiO4 at up to 1,300 gigapascals of pressure.

They found that post-post-spinel Mg2SiO4 is an exceptionally refractory mineral, meaning it can withstand extremely high temperatures before melting. Depending on the pressure, it melts at between 9,780 K and 14,897 K, significantly hotter than temperatures at which related minerals melt, including bridgmanite and MgSiO3 postperovskite, the high-pressure form of bridgmanite stable near Earth’s core-mantle boundary. Even after moderate amounts of iron were added, something that likely happens to some degree in most exoplanets, the melting point for post-post-spinel Mg2SiO4 remained above the temperatures estimated for the deep mantles of most rocky planets, the authors say.

Their results indicate that many super-Earths likely have solid deep mantles, which has implications for convection deep inside rocky exoplanets, as well as for their magnetic fields, which are created by swirling molten metals in their interiors. (AGU Advances, https://doi.org/10.1029/2026AV002326, 2026)

—Nathaniel Scharping (@nathanielscharp), Science Writer

Citation: Scharping, N. (2026), Super-Earths may be solid deep inside their mantles, Eos, 107, https://doi.org/10.1029/2026EO260256. Published on 7 August 2026. 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.

Author(s): James C. Welch, III, Louis Jose, Timothy D. Tharp, and Scott D. Baalrud

An important process for antimatter experiments is the cooling of particles in a Penning-Malmberg trap to experimentally useful temperatures. A non-neutral plasma of one species (e.g., antiprotons) can be collisionally cooled on another colder species (e.g., electrons). Modeling temperature relaxati…

[Phys. Rev. E 114, 025201] Published Thu Aug 06, 2026

In July 2026 I recorded 48 fatal landslides causing 413 fatalities. This year continues to be atypical in terms of the temporal pattern of fatal landslides.

This is my regular update for the number of fatal global landslides, focusing on July 2026. As usual, this data has been collected in line with the methodology described in Froude and Petley (2018) and in Petley (2012). References are listed below – please cite these articles if you use this analysis. Data presented in these updates should be treated as being provisional at this stage as I will reanalyse them prior to formal publication, and other events will emerge.

Note that this data excludes landslides triggered by earthquakes.

The headline figures are as follows:

July 2026: 100 fatal landslides causing 413 fatalities.

This is the number of landslides by month in 2026 to the end of July:-

The number of global fatal landslides in 2026 by month to the end of July.

We saw a massive uptick in fatal landslide occurrence in July 2026; indeed, this is the first time I have recorded 100 or more landslides in that month, and it is the third highest total in my dataset. This largely reflects an intense start to the South Asian Summer Monsoon.

My preferred way of presenting this data us to use the cumulative total by pentad. This graph is to pentad 42, which captures almost all of the July data (two landslides that occurred on 31 July 2026 are not included):-

The cumulative total number of global fatal landslides in 2026 by pentad to the end of July.

The steepening of the curve that is associated with the Northern Hemisphere rainy season is evident. 2026 continues to run a long way above the long term mean, and very close to the record year of 2024, even though the monthly pattern is markedly different.

It will be interesting to see what August 2026 brings.

References

Froude, M. and Petley, D.N. 2018.  Global fatal landslide occurrence from 2004 to 2016.  Natural Hazards and Earth System Sciences 18, 2161-2181.

Petley, D.N. 2012. Global patterns of loss of life from landslides. Geology 40 (10), 927-930.

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.

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.

Wildfires in the Canadian provinces of Ontario and the Northwest Territories have burned more than 3.9 million hectares this summer, prompted widespread evacuation orders, and created poor air quality for not only Canadians, but more than 120 million people across the midwestern and northeastern United States. The fires spread exceptionally quickly, stressing the resources of local response agencies. About 700 fires are still active across Canada.

 “The impacts of climate change are very real, and we can quantify what those are and the extent to which they have become more serious.”

According to a new analysis, human-induced climate change and its contribution to fire conditions across Canada made these fires twice as likely to occur. The report is from World Weather Attribution, an international climate science partnership. 

The analysis is an attribution study, which determines the extent to which climate change is responsible for a specific extreme weather event. Current science is best at determining climate change’s role in driving extreme temperatures and precipitation events, but wildfires are more difficult to attribute to climate change due to the many factors that drive their occurrence. Still, scientists’ attribution methods have greatly improved over the past decade, according to a recent report. 

“The impacts of climate change are very real, and we can quantify what those are and the extent to which they have become more serious,” said Theodore Keeping, a climate scientist at Imperial College London and coauthor of the new report.

Detected fire activity in Canada from 1-18 July, 2026. Study regions for the new World Weather Attribution analysis are represented by the two boxes overlaying the Northwest Territories and Ontario. Credit: World Weather Attribution

To determine the role of climate change in driving this summer’s Canadian wildfires, the research team analyzed the so-called Daily Severity Rating (DSR), a measure of fire weather that reflects how difficult it is to suppress a fire once it ignites. Using climate models, the team tested the likelihood that similar DSRs to those present in Ontario and the Northwest Territories this summer would occur in a hypothetical world without human-caused climate change.

Researchers determined that the sustained, severe DSRs present in Ontario and the Northwest Territories in July were made about twice as likely by climate change. The worst of the fire weather, a particularly high-DSR week in the Northwest Territories, was made about 27 times more likely by climate change, according to the researchers. 

However, such fire weather is “no longer rare in today’s climate,” the authors wrote. In a world without human-caused climate change, similar extreme fire events would have been expected about every 40 years. In our warming world, though, such fires are expected to occur every 2-6 years in the Northwest Territories and every 6-15 years in Ontario. 

Though a doubling of the likelihood of extreme fires may sound small, “a small change makes a huge difference for an ecosystem and a community,” said Frederike Otto, scientific lead of WWA and coauthor of the new report, in a press conference. The Canadian fires, she said, are “incredibly hard to suppress with the available people power and available technology. Even if [things get] just a little bit worse, it would mean that everything is stretched further.” 

Frequent Fires, Vulnerable People

The increasing occurrence of destructive fires means some communities are facing displacement repeatedly, especially as the last three fire seasons in Canada have been “exceptionally severe,” the authors wrote. 

Repeated extreme fire events make it difficult for communities to recover, and Indigenous communities are particularly vulnerable because they’re overrepresented in fire-prone areas. One 2024 study, for example, found that though Indigenous communities are only about 5% of Canada’s population, they made up 42% of its wildfire evacuations between 1980 and 2021. Fires in Ontario this summer have put thirteen First Nations communities under evacuation orders.

 
Related

•  Read the Report: “Climate Change More Than Doubled Extreme Fire Weather Conditions in Canada”
•  Natural Resources Canada: Climate Change and Wildland Fire
• We’re Getting Better at Knowing When Climate Change Is to Blame, National Academies Report Says
 

“Repeated displacement can disrupt cultural practices of Indigenous communities, as well as access to hunting grounds and traditional food,” said Chris Boyer, technical advisor and climate scientist at the Red Cross Red Crescent Climate Centre and coauthor of the new analysis, in a press conference. “Some of these communities are also dealing with the shortened response and recovery times between disasters due to the recent successive wildfires affecting longer-term resilience.”

“If you care about anyone but the super-rich, you have to stop burning fossil fuels,” Otto said. “The most vulnerable are hit hardest.”

—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 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.

Storm conditions capable of causing major coastal erosion at New Jersey's North Beach on Sandy Hook are occurring about twice as often as they did in 1979, according to Rutgers researchers. The finding offers new evidence that storm impacts are becoming more frequent along the Mid-Atlantic coast.

Fires in the Arctic are not solely a regional issue, as shown by the hazy skies in Switzerland last summer despite otherwise sunny weather. Smoke from major fires in northern Canada crossed the Atlantic and reached Europe. Until now, large-scale studies of Arctic tundra fires have focused primarily on rising temperatures and drought as the main drivers. The role of human activity has received much less attention, even as industrial development, settlements, roads and other infrastructure expand rapidly in parts of the Arctic, particularly in connection with extractive industries such as oil and gas production and mining.