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SummaryContinental intraplate regions exhibit slow deformation yet host destructive earthquakes, posing fundamental questions about strain partitioning far from plate boundaries. Here we combine a refined GNSS velocity field and elastic block modeling to investigate the Datong basin–range system in North China, a key intraplate deformation zone at the intersection of major fault systems and Quaternary volcanism. We find that left-lateral shear (∼2 mm/yr) and NW–SE extension (∼1 mm/yr) are accommodated across multiple faults and coherent block rotations, indicating broadly distributed deformation rather than localization on a single structure. Integration with mantle tomography reveals a low-velocity anomaly beneath Datong, suggesting that upwelling-driven thermal weakening augments far-field stresses from India–Asia collision and Pacific plate rollback. This deep–shallow coupling implies non-negligible seismic hazard and highlights the role of mantle dynamics in intraplate deformation.

SummaryLaterally distributed conductive bodies and intervening resistive regions within the transient electromagnetic (TEM) sensitivity region can produce anomalously enhanced responses over resistive zones. When interpreted with standard one-dimensional (1D) inversion, this response pattern can lead to laterally misplaced conductive anomalies. We refer to this family of inversion artefacts as array effects, because they arise when a subsurface array of conductive and resistive features jointly contributes to the measured TEM response, causing 1D inversion to recover conductive anomalies at incorrect lateral positions. The underlying physical cause is the conductive–resistive alternation mechanism: spatially separated conductive regions, interleaved with resistive gaps, can jointly influence the measured response, causing 1D inversion to place conductive anomalies into, or towards, intervening resistive regions. This produces severe artefacts in inversion models and can mislead geological interpretation. Such conditions may occur in geological settings characterized by repeated lateral electrical heterogeneity, provided that the electrical contrast and spacing are appropriate. Using smoke-ring theory and 3D numerical modelling, we investigate how these effects arise and propose the Instantaneous Smoke Ring Footprint (InSR-Footprint) as a practical criterion for model design and effect identification. Finally, we present field evidence for array effects in SkyTEM data acquired over a coastal dune environment in the Netherlands.

Two of the world's most fire-prone regions have followed strikingly different wildfire trajectories despite both experiencing a warming climate. Burned forest area has surged across the U.S. Southwest, while eastern Australia has not seen the same increase.

Coastal cities are at increasing risk of compound flooding events, such as when heavy rainfall and storm surges occur simultaneously during hurricanes. However, the processes that contribute to urban compound flooding aren't well understood at smaller scales.

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.

Over the past 2 weeks, large wildfires in southwestern France and central Spain have burned 255,000 hectares, displaced hundreds of thousands of people, and created extremely poor air quality even hundreds of kilometers away. Though firefighters have now contained the major fires, a forecasted heat wave and windy weather threaten to worsen the situation. 

Climate change played a role in creating the conditions for these fires to burn and spread, a new analysis has found.

The analysis, from World Weather Attribution, indicates that climate change made France and Spain’s fire-prone conditions much more likely: at least twice as likely in southwestern France and at least 20 times as likely in central Spain. Extreme heat and a widespread drought in Western Europe, both linked to climate change, created “tinderbox conditions,” the authors write.

“What we’re seeing in France and Spain isn’t just bad luck, it is a clear sign of the escalating impacts of anthropogenic warming,” said Clair Barnes, a climate scientist at Imperial College London and one of the authors of the analysis, in a press release.  

“We’ve seen repeatedly how climate change increases hot, dry, flammable conditions that are extremely conducive to wildfires. What’s unique about this case is that it’s still early in the season – and with another heatwave looming, these findings are extremely scary,” she said.

July wildfires have burned over a quarter of a million hectares (shaded in red) in Spain and France, as shown by European Forest Fire Information System (EFFIS) data. Climate change made these fires more likely. Credit: World Weather Attribution

Attribution studies typically compare weather and climate observations from the real world with a simulated, theoretical world in which the climate has not warmed. Through this method, scientists can get an idea of how likely a certain event would have been without climate change. 

World Weather Attribution, an international climate science partnership, said the researchers’ analysis used a “super-rapid” protocol that analyzed historical weather observations. Researchers compared this year’s fire weather conditions to the maximum fire weather conditions recorded in previous summers and simulations of conditions in a pre-industrial climate (a world without substantial anthropogenic climate change). 

Surface soil moisture anomalies relative to the 1991-2020 baseline in Spain and southeastern France show “weather whiplash”—a wet December, January, and February followed by a dry June and July. Credit: World Weather Attribution A historic heat wave in June put much of France under temperatures far above those of a 1991-2020 baseline. Credit: World Weather Attribution

Researchers determined that in France, drought-affected man-made pine woodlands created particularly suitable fuel for wildfires to spread rapidly. In Spain, a wet winter caused a spike in plant growth. When severe drought and high temperatures followed in spring and summer, a large volume of biomass became highly flammable fuel. This so-called “weather whiplash” is becoming “an increasingly important driver of wildfire risk in western Europe,” the authors write. 

Two previous attribution analyses by World Weather Attribution this summer found that Europe’s June heatwave and summer drought were both made more likely by climate change. A similar June heatwave would have been about 3.5°C (6.3°F) degrees cooler in 1976, for example, according to their analysis. 

“While this observation-based attribution study is well-designed and relies on established scientific literature,” the “super-rapid” protocol is limited in two ways, wrote Danielle Touma, a climate scientist at the University of Texas at Austin who was not involved in the study, in an email.

First, it’s difficult to assess the role of internal climate variability (natural fluctuations in the climate unrelated to climate change) without climate modeling, and second, it’s hard to assess the impact of increased carbon dioxide emissions on plant growth that could fuel fires. Still, “the methods that they use are well established for climate change-induced increases to temperatures and evaporative demand, which can lead to droughts,” she wrote.

 
Related

•  Read the Analysis: “Climate Change Increases Likelihood of Compounding Drivers of Severe Wildfire Conditions in France and Spain”
•  We’re Getting Better at Knowing When Climate Change Is to Blame, National Academies Report Says
 

Confidence in attributing events to climate change is highest for extreme temperature events, followed by precipitation events and drought. Scientists have relatively lower confidence in attributing wildfires to climate change due to the many drivers of fires. However, the science surrounding attribution studies has greatly improved over the past decade, according to a recent report from the National Academies of Science, Engineering, and Medicine. 

“These mega-fires show how fast climate-driven extreme heat and dry landscapes can turn wildfires into devastating national disasters,” said Simon Stiell, executive secretary of the United Nations Framework Convention on Climate Change, in a press release. 

“Humanity continuing to burn colossal amounts of coal, oil and gas is baking our planet, making these conditions more dangerous, and these megafires more deadly and destructive. But the solutions are equally clear: All countries must move faster from fossil fuels to renewables and protect people from worsening climate impacts, from wildfires, to megastorms and floods, to droughts hitting food production,” he said. 

—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
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Summer days featuring conditions that promote wildfire ignition, intensity and spread have more than doubled across large parts of the Iberian Peninsula, France, Italy and Greece since 1981, according to a study in Scientific Reports. The findings suggest that hotter, drier weather is increasing wildfire risk across Southern Europe, despite fewer fires occurring in the region since the 1980s.

When catastrophic wildfires capture global headlines, such as the unprecedented blazes sweeping through southern Europe this summer or the devastating 2019–20 "Black Summer" in Australia, they are almost always preceded by severe drought. Dry vegetation and parched landscapes are necessary ingredients for infernos.

The ocean absorbs roughly a quarter of humanity's carbon dioxide emissions each year. Understanding how that happens, and how it might change, is essential for predicting our climate's future. To do that, scientists need models that simulate not just the ocean's physical processes, such as currents and temperature, but the full web of biological and chemical processes that move carbon through the water column.

A 113-million-year-old marine murder mystery may finally be solved. Using chemical clues locked inside microscopic fossils, Northwestern University scientists found evidence that ocean acidification drove one of the largest extinction events in the history of planktic foraminifera—tiny shell-building organisms that help regulate Earth's carbon cycle.

Sea-surface salinity, the concentration of dissolved salts in the upper layer of the ocean, is much more than a measure of how salty the sea is. It responds rapidly to changes in rainfall, evaporation, river discharge and, specifically in polar regions, the melting and formation of sea ice. Salinity is both an important driver of ocean circulation and a tracer of the movement of water masses and surface currents.

Before rain falls, the moisture that forms it may have traveled anywhere from just a few kilometers to hundreds or even thousands of kilometers away. It usually begins as water that evaporated from oceans, lakes, forests or fields. According to a paper published in Geophysical Research Letters, rain in parts of the United States is increasingly arriving from farther away.

For around 12,000 years, the Earth has been in the Holocene epoch, a warmer period following a glacial period. During this epoch, however, there have been around 22 abrupt cold phases, each lasting up to several centuries and leading to the expansion of glaciers.

Source: Geophysical Research Letters

Coastal cities are at increasing risk of compound flooding events, such as when heavy rainfall and storm surges occur simultaneously during hurricanes. However, the processes that contribute to urban compound flooding aren’t well understood at smaller scales.

To better understand how different drivers of flooding interact near coastal cities, Xu et al. used the Energy Exascale Earth System Model (E3SM) with the River Dynamical Core (RDycore) shallow-water equation library built to simulate extreme flooding events. Their modeling highlights the importance of rural runoff for urban flooding events, the researchers say, while also underlining the continued role of coastal wetlands in blunting the dangers of compound flooding events.

The authors simulated 2011’s Hurricane Irene in the Delaware River basin. Using the kilometer-scale E3SM configuration allowed them to simulate flood dynamics at the building scale in many cases. They looked to see how factors such as runoff sources, interactions between rainfall and storm surge, and sea level rise affected flooding in urban areas near the coast. The biggest factor in severe flooding was topography, the authors say, especially in surrounding rural areas, where topographic features can funnel water toward cities. Features like the elevation change between outlying and urban areas and the connectivity of drainage systems had a significant effect on the severity of urban flooding.

Storm surges are predicted to become worse as sea levels rise, intensifying compound flooding. In their model, the authors re-created this effect but noted that most of the expanded flooding under sea level rise occurred in coastal wetlands, which acted to absorb much of the surge. This result is an indication of how valuable these ecosystems are for nearby urban areas, the authors say. (Geophysical Research Letters, https://doi.org/10.1029/2026GL122550, 2026)

—Nathaniel Scharping (@nathanielscharp), Science Writer

Citation: Scharping, N. (2026), How water flows toward cities during hurricanes, Eos, 107, https://doi.org/10.1029/2026EO260250. Published on 30 July 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.

The role of weather and environmental conditions in malaria transmission has long been recognized. Rainfall, temperature, and standing water all influence the life cycle of the female Anopheles mosquito, which spreads the malaria parasite Plasmodium falciparum. But what drives the conditions that make malaria outbreaks more or less likely?

A new study published in Communications Medicine found that temperatures in the Atlantic and Indian Oceans influence malaria risk in Malawi by altering the country’s environmental conditions. The researchers identified soil moisture as the key link connecting distant ocean temperature patterns to local malaria transmission.

Their work forms the basis for a potential forecasting tool, a much-needed innovation in a country like Malawi, where malaria remains one of the most prevalent infectious diseases, accounting for 7 million morbidity cases and 36% of outpatient visits in 2025.

Unlike rainfall and temperature, which fluctuate from day to day, sea surface temperatures evolve more slowly, making them potentially useful as malaria early-warning systems.

“In Malawi, there haven’t been a lot of studies on early warning signs for malaria transmission. So this was a first step in that direction.”

“In Malawi, there haven’t been a lot of studies on early warning signs for malaria transmission. So this was a first step in that direction,” said Maxwell Elling, a climate scientist at the University of Colorado Boulder and lead author of the study. “The idea is to incorporate all these factors that have a strong relationship with malaria and build a sort of statistical forecast that can help you, months in advance, to make a prediction of malaria incidence for that period.”

“Climate drivers like moisture and temperature don’t just affect the survival rates and habitats of vectors like mosquitoes but also of the pathogens themselves, including malaria parasites,” said Jessie Abbate, an infectious disease ecologist at the University of Virginia who was not involved in the study.

“These pathogens also have a range in which the weather is favorable for their development,” Abbate said. “So understanding how climate drivers influence changes in the weather and environment is hugely important.”

The team combined 19 years of district-level malaria records from Malawi with satellite and atmospheric datasets tracking sea surface temperatures, rainfall, and soil moisture. They then searched for ocean regions whose temperature fluctuations most strongly coincided with changes in malaria incidence.

“Oceans set off wave-like distributions and pressure that drive global winds,” Elling said. “So we wanted to ascertain how these factors influence weather changes in Malawi.”

Two Oceans, Two Effects

Two regions stood out: the tropical Atlantic Ocean and the central Indian Ocean. The researchers found that the two oceans exerted nearly opposite effects on Malawi’s climate.

When the tropical Atlantic was warmer than average, atmospheric circulation patterns transported warm, moist air into southeastern Africa. Rainfall increased, soils became wetter, and malaria incidence tended to rise.

“By and large, wind from the Atlantic drives the kind of environments that mosquitoes like: It’s warmer, more humid, and the soils are moist,” Elling said.

A warmer Indian Ocean produced a different outcome. Although warmer conditions were associated with some increases in rainfall, the additional heat also increased evaporation, drying out soils and creating conditions that were generally less favorable for mosquito breeding and malaria transmission.

Although previous studies have linked soil moisture to malaria transmission, soil moisture has received far less attention than rainfall and temperature.

“Products have been out there to analyze temperature and precipitation for decades,” Elling said. “But with soil moisture, the apparatus for monitoring, like satellite products, is relatively new.”

In the study, soil moisture emerged as the environmental variable most closely aligned with malaria incidence across Malawi.

“Soil moisture…tells us more about water sitting on the ground, which is an essential influence on the development of mosquitoes and their ability to transmit malaria.”

Unlike rainfall alone, soil moisture reflects the combined effects of precipitation, evaporation, and other land surface processes, making it a more direct measure of mosquito breeding conditions.

“Two main climate and environmental factors that these mosquitoes care about are temperature and standing water,” Elling said. “Soil moisture accounts for standing water better than just precipitation. It tells us more about water sitting on the ground, which is an essential influence on the development of mosquitoes and their ability to transmit malaria.”

Abbate agreed, arguing that as long as a link between soil moisture and infectious disease has been established, as in this study, “soil moisture is a much stronger predictor than precipitation. Because after precipitation events, it is the humidity of the soil that determines how much of that water sits in the ground and affects the development of the mosquitoes.”

A Drier Future but Not Necessarily Less Malaria

The researchers also examined what future climate change could mean for Malawi, a country that has already been described as “on the frontline of the climate crisis.” Using projections from nine global climate models, they found a consistent drying trend across the country by the end of the century. Average soil moisture declined by about 6% under a moderate-emissions scenario and roughly 11% under a high-emissions scenario, though the models disagreed on the magnitude of the change.

However, they cautioned that a drier future would not necessarily mean less malaria. Instead, transmission could shift geographically, becoming less likely in some regions while increasing in others.

Abbate also noted that the practical applicability of these long-term predictions depends on a range of factors, in part because pathogens and vectors can evolve over the course of 10 to 20 years.

“So regardless of how much mapping we do, it may not be what the future actually is,” she said. “A more practical approach would be to keep watching where the risk is increasing per time and shifting resources to those regions.”

More broadly, the researchers emphasized that climate is only one factor shaping malaria risk. Housing quality, health care access, socioeconomic conditions, and public health interventions also influence transmission and would need to be considered in any forecasting system.

Still, by showing that soil moisture connects large-scale climate variability to local transmission conditions, the work suggests that malaria outbreaks may be predictable months before they occur.

—Toluwalogo Niji-Olawepo (@Toluwalogo_), Science Writer

Citation: Niji-Olawepo, T. (2026), Distant oceans may help predict malaria risk in Malawi, Eos, 107, https://doi.org/10.1029/2026EO260243. Published on 30 July 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.

A new framework to cool urban areas which integrates AI-driven technical solutions with cooling schemes that are acceptable and doable for the host community, has been proposed by QUT Urban AI Hub researchers.

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

In near-Earth space, charged particles and plasma waves can exchange energy most effectively through resonance. Cyclotron resonance is one such interaction, where particles whose gyromotion synchronizes with the wave fields can gain or lose energy from waves, influencing phenomena such as the radiation belts, auroras, and space weather effects that can affect satellites and communication systems.

Li et al. [2026] explore the particular conditions leading to anomalous resonance, which occurs when cyclotron resonance is altered by very large amplitude of plasma waves. The distinguishing contribution of the study is the exploration of anomalous resonance in realistic inhomogeneous environments. The results prove that the interplay of resonances may give rise to an inhomogeneity-driven pathway for energy redistribution across a broader energy range than previously recognized. The above findings provide new insights into a fundamental and previously underappreciated mechanism shaping plasma dynamics across a wide range of space and astrophysical systems.

Ion and electron trajectories in wave field without (left column) and with (right column) background inhomogeneity. Panels (a) and (c) show the trajectories of high- and low-energy ions, respectively, in a uniform background. In panels (b) and (d), the corresponding trajectories are shifted by the background magnetic-field inhomogeneity. This inhomogeneity breaks the trajectory symmetry, enabling a net wave–particle energy transfer. Panels (e) and (f) show the trajectories of low-energy electrons, which are hardly affected by the background inhomogeneity. ζ is the gyro-phase difference between the particle’s perpendicular velocity and the wave magnetic field, and dζ/dt is its rate of change. Credit: Li et al. [2026], Figure 5

Citation: Li, J.-H., Zhou, X.-Z., Wang, S., Liu, Z.-Y., Khotyaintsev, Y. V., Graham, D. B., et al. (2026). Bidirectional energy transfer via simultaneous wave-particle resonances in inhomogeneous space plasmas. AGU Advances, 7, e2026AV002479. https://doi.org/10.1029/2026AV002479

—Alberto Montanari, Editor-in-Chief, AGU Advances

Text © 2026. The authors. CC BY-NC-ND 3.0
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A new study provides a fascinating insight into the patterns of landslide exposure in the United States.

The increased focus in recent years on the socio-economic aspects of landslides has been welcome. This area of understanding has lagged behind that for other hazards, possibly in part because of the lack on interest from the insurance industry. Increasing evidence of the societal cost of landslides, for example in New Zealand, is shifting the focus.

A really interesting open access paper (Acosta-Reyes et al. 2026) has just been published in the AGU journal Earth’s Future that examines societal exposure to landslides in the United States. This has been reported by some parts of the mainstream media too, which is welcome given that this is a fascinating study.

This study is underpinned by the landslide susceptibility map for the United States developed by the USGS. Acosta-Reyes et al. (2026) have then combined this with two other datasets – an inventory of buildings (the U.S. Army Corps of Engineers (USACE) National Structure Inventory), which includes 128 million structures, and a national scale social vulnerability dataset (the Social Vulnerability Index).

The headlines from the study are important. Whilst terrain with high landslide susceptibility covers 19% of the land area of the United States, only 2% of the population resides within these areas (although this still represents 6.5 million people).

There is huge richness in this study, but allow me to focus on just two elements. First, this map shows the population exposure to high landslide susceptibility:-

Population exposure to high landslide susceptibility in the United States from Acosta-Reyes et al. (2026). Original caption: “National distribution of population exposure to high landslide susceptibility. Building-level LED population estimates aggregated to the census tract level. Map projected in Albers Equal Area Conic (EPSG:5070); Alaska and Hawaii are displaced from their geographic locations for visualization, with Alaska displayed at 50% of native scale.”

This shows that the most exposed populations are in the Appalachian Highlands and in the Pacific Mountain System, with more isolated areas of higher exposure elsewhere across the country.

Second, we know well that poverty greatly increases the potential human outcomes of geophysical hazards – poorer people suffer more from natural hazards. So this map is absolutely fascinating and very important:-

Poverty characteristics of the population exposed to high landslide susceptibility in the United States from Acosta-Reyes et al. (2026). Original caption: Income and poverty characteristics of the population exposed to high landslide susceptibility at the census-tract scale. (a) … (b) High-exposure population residing in tracts with poverty rates of 20% or higher. Insets for Alaska and Hawaii use a modified scale and geographic displacement for visual clarity.

There are 732,000 individuals represented in this map, but the population is hugely concentrated in the southern Appalachians. These are comparatively poor rural communities. Globally, measures to address this exposure to landslides rarely focuses on these communities, but they are so very important.

Acosta-Reyes et al. (2026) consider carefully the policy implications of these highly exposed communities living in poverty:

“Addressing these conditions requires combining hazard mitigation with broader resilience investments: early warning systems tied to precipitation forecasts can reduce harm during extreme rainfall events; temporary relocation services provide immediate protection during acute hazard periods; and for exposed households in high-risk terrain, voluntary property acquisition programs (such as FEMA’s Hazard Mitigation Grant Program) offer a long-term strategy to permanently reduce exposure, an approach already applied in parts of Appalachia for flood hazard with demonstrated benefit-cost ratios … These communities typically lack the local fiscal capacity to implement mitigation measures independently, and without sustained federal and state investment, the gap between exposure and adaptive capacity will remain.”

Translating this into policy change is very difficult, but we now have the information that highlights the need for action.

Reference

Acosta-Reyes, D. et al. 2026. Landslide exposure in the United States. Earth’s Future, e2026EF008622. https://doi.org/10.1029/2026EF008622Digital Object Identifier (DOI)

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Assessing how climate change will affect different regions usually requires running a complex chain of models. While this approach provides valuable insights, it is expensive and can cover only a limited set of scenarios and model runs. Together with partners, IIASA researchers have developed a faster alternative that uses available projections from Earth system or climate impact models to generate new regional climate and impact projections while capturing the uncertainty essential for understanding climate risk.

SummarySeismic surface wave tomography uses surface wave information to obtain velocity structures in the subsurface. Due to data noise and nonlinearity of the problem, surface wave tomography often has non-unique solutions. It is therefore required to quantify uncertainty of the results in order to better interpret the resulting images. Bayesian inference is the most widely-used method for this purpose. However, the commonly-used Monte Carlo methods require huge computational cost and remains intractable in high-dimensional problems. Variational inference uses optimization to solve Bayesian inverse problems, and therefore can be more efficient in the case of large datasets and high-dimensional parameter spaces. Variational inference has been widely applied to 2-D phase velocity map inversion. In this study, we extend the method to 3-D surface wave tomography by directly inverting for 3-D spatial seismic velocity structures from frequency-dependent travel time measurements. Specifically, we apply three variational methods, mean-field automatic differential variational inference (mean-field ADVI), physically structured variational inference (PSVI) and stochastic Stein varational gradient descent (sSVGD) to surface wave tomographic problems using both synthetic data and real data in the Southwest China. The results show that all methods can provide accurate velocity mean estimates, while sSVGD produces more reasonable uncertainty estimates than mean-field ADVI and PSVI because of Gaussian assumption used in these methods. In the real data case, the variational methods provide more detailed velocity structures than those obtained using traditional linearized methods, along with reliable uncertainty estimates. We therefore conclude that variational surface wave tomography can be applied fruitfully to many realistic problems.

SummaryOn 21 May 2021, a moderate earthquake with a magnitude of M6.4 occurred in western Yunnan Province, China. Several felt earthquakes had occurred in the region in the three days preceding this event. We aimed to investigate whether there are indications of crustal fluid migration in this region and, if so, the extent to which regional seismicity might be influenced by crustal fluids. Using the epidemic-type aftershock sequence (ETAS) model, we analyzed the earthquake triggering process and the nonstationary background rate. In addition, seismicity rates were used to estimate Coulomb stress changes. Specifically, the results suggest that the background rate increased from 0.2 to 15 events per day during the Yangbi earthquake sequence, and the spatial evolution of the background rate was broadly consistent with a fluid diffusion pattern. The evaluated cumulative stress change indicates that the stress rate increased by approximately 50 per cent following the M6.4 earthquake. Spatial stress changes suggest migration and expansion of regions with increased stress. These results imply the presence of crustal fluid flow in the study area, with a tendency to diffuse southward.