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Solar Orbiter isn’t the first spacecraft to study the sun’s poles—but it’s the first to send back photographs

NASA employees have until July 25 to decide if they’ll stay or go.

Gun violence is the leading cause of death of children in the U.S.—and states with loose gun control laws bear the heaviest burden, a new study found

Grab a Lego set worthy of the Lisan al Gaib with the Lego Dune Ornithopter.

Scientists find surprising evidence that space dust is shaping the surfaces of Uranus’ largest moons.

This month’s full Strawberry Moon rides low across the southern sky via livestream on June 11.

In two related firsts, the James Webb Space Telescope has discovered sand-filled rains on a distant exoplanet as its “sandcastle” partner world forms from sandy matter before the eyes of astronomers.

30 people have been evacuated in Les Epenays and Fregnoley in the Val de Bagnes in Valais due to the threat of debris flows .

As the dust settles on the landslide crisis at Blatten, Swissinfo has published a very nice article highlighting the growing landslide risk in Switzerland. For example, in the canton of Graubünden (which is the focus of the article) alone, 17,000 buildings are located in high natural hazard areas. Over 5,000 of these are residential properties.

Right on cue, another significant landslide crisis has developed in Switzerland, this time in in the upper Val de Bagnes in Valais. Here, an ongoing slope collapse is generating debris flows that are affecting the village of Les Epenays. Thirty people have been evacuated. Blue News has published a nice article that summarises the threat. Parts of another hamlet, Fregnoley, are also at some risk, and two farms have been evacuated there as well.

The evolution of this crisis is best told with a series of Planet Labs satellite images. So, to start, this is the site on 28 June 2024. The marker, which is located at [46.06612, 7.26522], is in the upper part of the catchment that is causing the problems.

This is a typical alpine subcatchment, with steep upper slopes and some incision. How let’s jump forward a week to 5 July 2024:-

The site had dramatically changed, the result of intense rainfall. In the upper part of this subcatchment, slope failure had occurred. Lower down the slope a large alluvial fan has developed, and the image shows that the road has been inundated. Further debris flows occurred through summer 2024.

In the last week, storms have further exacerbated the issues. This is an image collected on 8 June 2025:-

Note the dramatic increase in instability in the upper portions of the catchment (especially in the area of the marker) and the huge area inundated by the debris flows downstream. This acceleration in activity was driven by a storm on 1 June 2025.

It is interesting to compare the June 2024 and June 2025 images:-

What a difference a year makes!

The Commune of Val de Bagnes has also released this image of the impact of the debris flows on the road:-

The Commune of Val de Bagnes is publishing daily updates. The bulletin published yesterday highlighted that the slopes in the upper catchment that are generating these debris flows are currently moving at up to 2 metres per day.

Clearly, this issue is less acute than the one at Blatten, but it is serious headache nonetheless. The Alps are prone to thunderstorms with intense rainfall in the summer months, so this could be a trying period for the local community and for the authorities in Vallais.

Acknowledgement and reference

Thanks to loyal reader Alasdair MacKenzie for highlighting the article on landslide risk in Graubünden. And thanks also to Planet Labs for their wonderful imagery, again.

Planet Team 2025. Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https://www.planet.com/

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

Source: AGU Advances

As the global climate continues to warm, fire seasons have intensified, and large-scale wildfires have become more frequent in many parts of the world. Factors such as vegetation type, land use patterns, and human activity all affect the likelihood of ignition, but wildfire proliferation ultimately depends on two factors: climate and fuel availability.

Kampf et al. studied relationships between fire, fuel, and climate in temperate regions around the world, focusing specifically on western North America, western and central Europe, and southwestern South America. Each of the three regions includes desert, shrub, and forest areas, as well as local climates ranging from arid to humid.

The researchers pulled information on total burned area and wildfire frequency in these regions between 2002 and 2021 from the GlobFire database, and they sourced data on land cover and biomass during the same period from NASA’s Global Land Cover Mapping and Estimation (GLanCE). They also used precipitation and evapotranspiration data from TerraClimate to calculate the mean annual aridity index (mean annual precipitation divided by mean annual evapotranspiration) for each region.

The researchers found that over the 20-year study period and across all three regions, fires burned smaller areas of land in zones with either very dry climates or very wet climates compared with zones of intermediate aridity. They suggest that this trend is explained by the lack of vegetation sufficient to fuel widespread fires in dry zones and, in wet zones, by weather conditions that dampen the likelihood of fires. In contrast, burned areas were larger in the intermediate zones where biomass abundance and weather conditions are more conducive to fueling fires.

Of the three regions studied, North America had the largest total burned area, fraction of area burned, and fire sizes. The researchers note that the fragmentation of vegetated areas in South America (by the Andes Mountains) and in Europe (because of extensive land use) has likely limited the sizes of fires and burned areas in those regions. They also point out that rising temperatures and aridity are increasing the risk of large wildfires in all three regions, suggesting that fire managers need to be flexible and responsive to local changes. (AGU Advances, https://doi.org/10.1029/2024AV001628, 2025)

—Sarah Derouin (@sarahderouin.com), Science Writer

Citation: Derouin, S. (2025), The Goldilocks conditions for wildfires, Eos, 106, https://doi.org/10.1029/2025EO250215. Published on 9 June 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.

Editors’ Vox is a blog from AGU’s Publications Department.

A recent article in Reviews of Geophysics explores land subsidence drivers, rates, and impacts across the globe. It also discusses the need for improved process representations and the inclusion of the interplay among land subsidence and climatic extremes, including their effects in models and risk assessments. Here, we asked the lead author to explain the concept of land subsidence, its impacts, and future directions needed for improved mitigation.

What is land subsidence? 

Land subsidence (LS) refers to the relative sinking or lowering of the Earth’s land surface. LS is a pressing global issue that warrants action since subsidence can adversely impact infrastructure, humans, and the environment across various landscapes and climates (Figure 1). It may be driven by one or more natural processes and/or human activities that compound to cause localized or expansive ground deformation. Differential LS causes structures and roadways to crack and buckle. LS can also reduce the water storage capacity of aquifers. Notably, LS can be recoverable (e.g., natural variations in groundwater levels) or permanent (e.g., overdraft causing irreversible compaction).  

Why is it important to understand and monitor land subsidence? 

Various LS drivers and physical processes exist and interact with one another (Figure 1). LS is often closely related to natural resources demand, which increases with growing urbanization and megacities. The proximity of LS to critical infrastructure like water conveyance, transportation, and utility systems is a significant concern since LS could cause catastrophic lifeline failures, outages, and/or loss of life. Also, feedbacks between climatic extremes (e.g., droughts, floods, wildfires, heatwaves) and LS impacts exist, but are not fully understood.

Although a chronic hazard, LS may initially go unnoticed as sinking typically occurs slowly. This influences perceived risk and contributes to reactive policies, regulations, and mitigation steps targeting LS and its implications rather than proactive measures. Furthermore, the compounding effects of extreme events and their impacts can exacerbate LS. More pronounced interactions are likely with projected rises in climate extremes.

How do scientists monitor and measure land subsidence across the globe? 

Scientists use various techniques and technologies to measure LS, including ground-based surveys, subsurface instrumentation, and satellite-based observations. Satellite-based Synthetic Aperture Radar (SAR) has revolutionized LS monitoring and mapping. It is an active remote sensing system that emits microwave pulses and receives echoes. Such systems can operate under various conditions (e.g., day and night, in cloudy skies) and produce high-resolution imagery. With SAR-based information, scientists can infer surface deformation by computing phase differences between SAR snapshots over a region using techniques like interferometric SAR (InSAR). SAR-based observations commonly inform impact assessments for agriculture, structural health, and resource management.

What are the major natural and anthropogenic drivers of land subsidence? 

Naturally-occurring processes and human activities can independently drive LS or enhance existing LS rates (Figure 2). Some examples of natural drivers of LS include: natural consolidation, volcanic or tectonic activity, seasonal groundwater level variations, and soil organic material decomposition. Extraction of natural resources (e.g., fossil fuels, groundwater), removal of wetlands and peatlands, and loading from rapid urbanization serve as examples of human-related activities contributing to LS. Natural resource extraction is a leading anthropogenic driver of LS (Figure 1), which often rises with increasing population. Also, extreme events such as wildfires or heatwaves can trigger LS in permafrost areas by thawing the permafrost layer, altering the soil structure, and releasing greenhouse gases that accelerate warming.

How is land subsidence projected to change in the future? 

Estimating future LS rates is challenging. Projecting human activities driving LS and the effectiveness of restoration and mitigation efforts is complicated, uncertain, and variable. LS projections also depend on other factors (e.g., infrastructure investments, land use-land cover changes). They are further complicated by uncertain projected hydrologic variables like precipitation. Yet, more people are expected to be exposed to LS with greater economic losses anticipated in the future.

Sea level rise (SLR), rising temperatures, and extreme events often compound LS. Subsiding coastal areas and deltas face higher inundation risk from the compounding effect of SLR. Extreme events and LS impacts are expected to increasingly affect one another (Figures 2-3) as extremes (e.g., drought) intensify with warming. Amidst drought, groundwater levels drop through decreased recharge and increased pumping, often leading to soil compaction and LS. As soils dry and crack, heightened microbial processes decompose soil organic matter and release carbon. Such processes can enhance warming while triggering LS and feedbacks. As temperatures rise, permafrost thaw-driven LS is also expected to expand, increasing the infrastructure at risk for damage and failure.

What additional research, data, or modeling is needed to help track and mitigate land subsidence and its impacts? 

Integrated models incorporating multiple LS drivers and processes are necessary for better estimating LS rates, extent, and ramifications at the spatiotemporal resolutions essential for mitigation, adaptation, and policy. Additional data and research are needed to understand the interplay of extreme events, infrastructure, climatic trends, and human activities with LS dynamics and effects (Figure 3), and inform LS mitigation efforts.

Improved climate modeling, management practices, and risk assessments require better representations of LS feedbacks, carbon emissions, and LS processes. Such advancements necessitate accurate, longer, and spatial observations and analyses with improved process understandings. Global adoption of consistent monitoring and reporting frameworks will also support such efforts by leading to new insight into LS observations and regions at-risk for LS, LS-enhanced flooding, etc. Interdisciplinary efforts will help transform science into action focused on LS hazard and risk mitigation.

—Laurie S. Huning ([email protected], 0000-0002-0296-4255), California State University, Long Beach, United States

Editor’s Note: It is the policy of AGU Publications to invite the authors of articles published in Reviews of Geophysics to write a summary for Eos Editors’ Vox.

Citation: Huning, L. S. (2025), Rising concerns of climate extremes and land subsidence impacts, Eos, 106, https://doi.org/10.1029/2025EO255019. Published on 9 June 2025.

This article does not represent the opinion of AGU, Eos, or any of its affiliates. It is solely the opinion of the author(s).

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Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.