EOS

The annual Asian monsoon is one of the most consequential components of the global climate system, pivotally affecting water availability, agriculture, and livelihoods for billions of people across much of East, South, and Southeast Asia. Even modest shifts in the timing or intensity of monsoon rainfall in a given location can lead to flooding, drought, and cascading socioeconomic impacts.

In 2024, for example, exceptionally heavy rains inundated large areas of eastern Bangladesh, affecting millions of people, damaging crops, and disrupting transportation and essential services. In contrast, delayed or below-average monsoon rainfall in parts of India has repeatedly reduced crop yields and strained water supplies, illustrating how both excess and deficient rainfall can have far-reaching consequences for food security and regional economies.

Despite decades of research, predicting the Asian monsoon’s variability from place to place and year to year remains difficult.

Despite decades of research into the complex interplays of tropical ocean conditions, land-atmosphere feedbacks, and large-scale circulation that drive the monsoon, predicting its variability from place to place and year to year remains difficult.

Traditionally, scientists have focused on studying tropical drivers such as the El Niño–Southern Oscillation (ENSO) and Indian Ocean variability. Increasingly, however, attention is turning toward processes far outside the tropics. Rapid environmental change in the Arctic, particularly the decline of sea ice, is emerging as a potential contributor to atmospheric variability that may extend into monsoon regions.

The Arctic is warming nearly 4 times faster than the global average, a phenomenon known as “Arctic amplification.” And since satellite observations of Arctic sea ice began in 1979, summer (minimum) sea ice extent has declined sharply—by about 12% per decade—exposing larger expanses of ocean surface, which absorbs more solar radiation than ice does, and accelerating regional warming [Screen and Simmonds, 2010; Serreze and Barry, 2011].

Arctic sea ice extents and concentrations have declined substantially in recent decades. The minimum ice extent in 2024, shown here, covered far less area compared with the 1981–2010 median. Credit: NOAA Climate.gov image, based on data from the National Snow and Ice Data Center

These changes are often framed as primarily polar concerns, but a growing body of research suggests they may also influence atmospheric circulation patterns affecting distant regions, including the Asian monsoon.

Arctic Amplification and the Jet Stream

Arctic amplification, driven largely by sea ice loss and albedo feedbacks [Screen and Simmonds, 2010; Serreze and Barry, 2011], reduces the equator-to-pole temperature gradient, a key driver of midlatitude atmospheric circulation. This effect has motivated one of the most widely discussed hypotheses about modern climate dynamics: that Arctic warming alters the behavior of the jet stream in ways that affect weather and climate at lower latitudes [Francis and Vavrus, 2012, 2015].

The hypothesis proposes that a weaker meridional (north–south) temperature gradient leads to reduced zonal (west–east) wind speeds and increased meridional meandering of the flow of the jet stream. In this framework, a “wavier” jet stream favors more persistent ridges and troughs, potentially allowing high-latitude weather anomalies to propagate into Eurasia and influence subtropical systems.

Though influential, this idea is far from settled. Subsequent studies have both supported and challenged different aspects of the hypothesis. Some observational analyses, for example, have suggested that episodic increases in the jet stream’s wave amplitude and the frequency of blocking events (stationary high-pressure systems that block other weather systems from moving through an area) are consistent with a weakened jet [Francis and Vavrus, 2015; Coumou et al., 2018]. Others, however, have found that internal atmospheric variability or forcing by tropical conditions alone can explain much of the jet stream’s observed behavior without requiring a prominent Arctic contribution [Barnes and Screen, 2015; Blackport and Screen, 2020].

Unraveling the nuanced cause-and-effect relationships between the Arctic and the jet stream is essential for interpreting potential downstream effects on the Asian monsoon.

Climate model experiments have further complicated the picture. Whereas some simulations reproduce jet stream responses consistent with the Francis-Vavrus mechanism, others show weak, negligible, or even opposite responses. These discrepancies arise in part because modeled atmospheric responses to Arctic forcing are sensitive to background conditions, including sea surface temperatures, stratospheric variability, and how transient eddies in the atmosphere are represented.

Meanwhile, synthesis studies have emphasized that Arctic amplification does not seem to produce a robust, uniform response in the jet stream. Instead, its influence appears to depend on season, region, and interaction with other climate drivers. In this view, Arctic change may alter the likelihood of certain circulation regimes, such as blocking patterns, occurring at given times and places, rather than causing lasting, systematic shifts.

Unraveling the nuanced cause-and-effect relationships between the Arctic and the jet stream, as a large body of recent research has aimed to do, is essential for interpreting potential downstream effects on the Asian monsoon.

Emerging Evidence of a Complex Connection

Recent studies have begun to investigate Arctic-monsoon linkages explicitly, though their results also reveal a complex picture.

Duo and Zhang [2025] used a combination of observational datasets and climate model simulations from the Coupled Model Intercomparison Project Phase 6 (CMIP6) to examine late-season (autumn) monsoon dynamics over Southeast Asia. Their analysis showed that reduced Arctic sea ice is associated with delayed monsoon retreat and increased rainfall during the postmonsoon transition, which the researchers attributed to Arctic-induced circulation changes weakening zonal winds and enhancing moisture convergence over Southeast Asia. Their results highlight that Arctic forcing may influence not only seasonal precipitation averages but also monsoon timing.

Zhang et al. [2024] used reanalysis data alongside coupled climate model experiments from the Polar Amplification Model Intercomparison Project (part of CMIP6) to explore interdecadal variability in the East Asian summer monsoon. They found that Arctic sea ice loss can generate stationary wave responses across Eurasia that alter circulation in the upper troposphere and modulate monsoon strength and rainfall distribution. Their simulations also suggested that Arctic forcing contributes to longer-term variability in monsoon circulation and rainfall that is superimposed on anthropogenic warming trends.

Recent studies indicate that declining Arctic sea ice does not trigger a uniform monsoon response.

In other work, Sardana and Agarwal [2025] examined the influences of spring sea ice variability in the Barents and Kara Seas on the Indian summer monsoon using 6 decades of observational data. They reported that reduced sea ice in the Barents-Kara region is associated with suppressed rainfall over northern India, proposing that the shortage of sea ice alters large-scale atmospheric circulation patterns and weakens moisture transport into the subcontinent.

The studies above indicate that declining Arctic sea ice does not trigger a uniform monsoon response. Whereas Duo and Zhang [2025] identified enhanced late-season rainfall as a result of sea ice loss, Sardana and Agarwal [2025] found that it suppressed monsoon rainfall. Zhang et al. [2024], meanwhile, showed that Arctic sea ice loss modulates long-term variability in the East Asian summer monsoon rather than producing a consistent increase or decrease in monsoon rainfall.

These differences likely arise because of the different regions, seasonal timings, and teleconnection pathways considered in each study. Rather than contradicting one another, however, the studies collectively suggest that Arctic influences on the Asian monsoon are spatially and temporally heterogeneous.

How Arctic Signals Travel South

In addition to outlining monsoon effects associated with Arctic sea ice loss, recent research has proposed several mechanisms to explain physically how ice loss may influence storm systems thousands of kilometers away (Figure 1).

Fig. 1. Arctic sea ice loss may be linked to Asian monsoon variability in a variety of ways, including those illustrated here. Declining sea ice enhances Arctic amplification and weakens the equator-to-pole temperature gradient, altering the jet stream’s structure, the propagation of Rossby waves, and land temperatures across Eurasia. These atmospheric adjustments may then influence the timing, intensity, and spatial distribution of Asian monsoon rainfall, including delaying monsoon retreat. Credit: Neha Kushwaha

Jet stream modulation is one possible mechanism. As noted earlier, Arctic amplification can alter atmospheric temperature gradients and the strength and structure of the polar jet stream. A wavier jet may favor persistent ridges and troughs over Eurasia that can promote the divergence of winds in upper atmospheric layers, as well as vertical motion and moisture transport relevant for monsoon dynamics [Serreze and Barry, 2011].

The propagation of Rossby waves, large-scale atmospheric waves driven by Earth’s rotation, is another potential mechanism. Changes in heat fluxes and pressure-temperature conditions (i.e., geopotential heights) over the Arctic surface may excite stationary Rossby wave trains that propagate into Eurasia. These wave trains can reorganize subtropical high-pressure systems and monsoon troughs, thereby affecting atmospheric convection and rainfall distribution [Zhang et al., 2024; Duo and Zhang, 2025].

Land-atmosphere feedbacks, including Arctic-induced circulation changes, can enhance warming over Eurasia, particularly during spring. This warming may modify land-sea thermal contrasts, a key driver of monsoon circulation. Changes in snow cover and soil moisture can amplify or dampen these contrasts, introducing additional regional variability [Serreze and Barry, 2011; Zhang et al., 2024].

An emerging line of research suggests that Arctic variability may also influence monsoons indirectly via the stratosphere. Sea ice loss can modify the flux of Rossby waves entering the stratosphere, potentially weakening the polar vortex. The resulting atmospheric circulation anomalies can propagate downward from the stratosphere into the troposphere and affect midlatitude circulation patterns that govern monsoon systems [Barnes and Screen, 2015].

The effects of transient eddies in the atmosphere add additional complexity. Changing Arctic temperature gradients can modify eddy formation, influencing how energy is transferred and, in turn, affecting both large-scale wave patterns and the growth and decay of synoptic weather systems that contribute to monsoon variability.

Limitations on Current Understanding

The Arctic-monsoon connection does not occur via a single linear pathway but through a network of interacting atmospheric processes operating across scales.

The variety of mechanisms above demonstrates that the Arctic-monsoon connection does not occur via a single linear pathway but through a network of interacting atmospheric processes operating across scales. Despite growing interest in this connection, substantial uncertainties remain regarding the relative importance and robustness of different mechanisms and their specific effects on the Asian monsoon. Resolving these uncertainties is not an easy problem to parse.

Tropical drivers such as ENSO continue to dominate interannual monsoon variability, often overshadowing the effects of high-latitude influences [Turner and Annamalai, 2012]. Furthermore, observational records of Arctic sea ice and its relationship with Asian monsoon variability are relatively short compared to the timescale of Arctic change, limiting our ability to detect robust, long-term relationships [Barnes and Screen, 2015].

Studies using climate models show considerable spread in monsoon responses to Arctic forcing. Differences in model resolution and representations of sea ice and atmospheric dynamics lead to varying outcomes, including in the magnitude and even direction of monsoon responses.

Another key uncertainty lies in the timescales of responses. Although some studies identify interannual links between Arctic variability and monsoon behavior, others emphasize decadal or longer-term modulation [Zhang et al., 2024; Sardana and Agarwal, 2025]. This distinction raises an important question: Are observed relationships indicative of a persistent physical connection, or do they emerge intermittently under favorable background conditions? Addressing this question will require the availability of longer observational records and conducting targeted model experiments designed to isolate the effects of Arctic forcing.

Furthermore, interactions between Arctic and tropical drivers remain poorly constrained. For example, Arctic-induced atmospheric circulation anomalies may reinforce or counteract ENSO-related patterns. This nonlinearity complicates attribution and suggests that Arctic influences are best understood within a multidriver framework, rather than in isolation.

Why This Matters in a Warming World

Understanding Arctic-monsoon teleconnections is not merely an academic exercise; rather, it carries significant implications. The monsoon underpins food security, water resources, and economic stability across much of Asia. If changing Arctic conditions influence background atmospheric states, they may undermine these crucial needs by affecting the likelihood and timing of rainfall and drought, including extreme events.

Ice loss may act as a risk amplifier, subtly reshaping the conditions under which monsoons evolve.

Although current evidence does not support a simple causal chain between Arctic sea ice decline and effects on the Asian monsoon, ice loss may act as a risk amplifier, subtly reshaping the conditions under which monsoons evolve. As Arctic warming continues and the region undergoes further rapid transformation, whether and how these teleconnections could strengthen and interact with other climate drivers in complex ways remain open questions.

Recognizing these connections challenges the traditional view of monsoons as purely tropical systems and highlights the need for a hemispheric perspective in climate research and prediction. Improving seasonal forecasting, refining climate projections, and anticipating extreme events will increasingly require accounting for cross-latitude interactions.

The Arctic-monsoon connection ultimately illustrates a broad principle: Climate change is not simply a collection of independent regional trends, but a global network of linked processes. Understanding these links is essential for managing risk in a world where distant changes can have local consequences.

References

Barnes, E. A., and J. A. Screen (2015), The impact of Arctic warming on the midlatitude jet-stream: Can it? Has it? Will it?, Wiley Interdiscip. Rev. Clim. Change, 6(3), 277–286, https://doi.org/10.1002/wcc.337.

Blackport, R., and J. A. Screen (2020), Insignificant effect of Arctic amplification on the amplitude of midlatitude atmospheric waves, Sci. Adv., 6(8), eaay2880, https://doi.org/10.1126/sciadv.aay2880.

Coumou, D., et al. (2018), The influence of Arctic amplification on mid-latitude summer circulation, Nat. Commun., 9(1), 2959, https://doi.org/10.1038/s41467-018-05256-8.

Duo, Y., and J. Zhang (2025), Arctic ice loss is delaying monsoon retreat over the Indochina Peninsula, npj Clim. Atmos. Sci., 8, 364, https://doi.org/10.1038/s41612-025-01241-3.

Francis, J. A., and S. J. Vavrus (2012), Evidence linking Arctic amplification to extreme weather in mid-latitudes, Geophys. Res. Lett., 39(6), L06801, https://doi.org/10.1029/2012GL051000.

Francis, J. A., and S. J. Vavrus (2015), Evidence for a wavier jet stream in response to rapid Arctic warming, Environ. Res. Lett., 10(1), 014005, https://doi.org/10.1088/1748-9326/10/1/014005.

Sardana, D., and A. Agarwal (2025), Impact of spring sea ice variability in the Barents-Kara region on the Indian summer monsoon rainfall, Sci. Rep., 15, 37790, https://doi.org/10.1038/s41598-025-21544-y.

Screen, J. A., and I. Simmonds (2010), The central role of diminishing sea ice in recent Arctic temperature amplification, Nature, 464, 1,334–1,337, https://doi.org/10.1038/nature09051.

Serreze, M. C., and R. G. Barry (2011), Processes and impacts of Arctic amplification, Global Planet. Change, 77, 85–96, https://doi.org/10.1016/j.gloplacha.2011.03.004.

Turner, A. G., and H. Annamalai (2012), Climate change and the South Asian summer monsoon, Nat. Clim. Change, 2(8), 587–595, https://doi.org/10.1038/nclimate1495.

Zhang, X., et al. (2024). The role of Arctic sea ice loss in the interdecadal trends of the East Asian summer monsoon in a warming climate, npj Clim. Atmos. Sci., 7, 174, https://doi.org/10.1038/s41612-024-00717-y.

Author Information

Neha Kushwaha (neha24@iiserb.ac.in), Indian Institute of Science Education and Research Bhopal, India

Citation: Kushwaha, N. (2026), Arctic sea ice loss may be reshaping the Asian monsoon, Eos, 107, https://doi.org/10.1029/2026EO260249. Published on 29 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.

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

Rising atmospheric carbon dioxide (CO₂) is cooling the upper atmosphere, but it is also changing how the atmosphere responds to natural disturbances. One important example is a sudden stratospheric warming (SSW), a wintertime event that disrupts atmospheric circulation from the stratosphere to the edge of space. Because SSWs can alter the ionosphere, they can affect satellite operations, radio communications, and navigation systems.

Using a whole-atmosphere model, Kumar et al. [2026] investigate how the atmospheric response to strong SSW changes in a future climate with doubled CO₂. They find that CO₂-driven cooling changes upper-atmosphere winds, making the response increasingly different between the Northern and Southern Hemispheres. These changes produce larger hemispheric differences in atmospheric composition and ionospheric plasma density. The study provides new insight into how climate change could influence future space weather and its impacts on modern technology.

Citation: Kumar, S., Oberheide, J., & Martinez, B. C. (2026). Impact of doubled CO2 on the response of the mesosphere, thermosphere, and ionosphere to the 2008–2009 sudden stratospheric warming. Geophysical Research Letters, 53, e2026GL121817. https://doi.org/10.1029/2026GL121817  

—Huixin Liu, Editor, Geophysical Research Letters

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In June 2026 I recorded 48 fatal landslides causing 131 fatalities. 2026 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 June 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:

June 2026: 48 fatal landslides causing 131 fatalities.

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

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

Last month I once again noted that 2026 was proving to be atypical in terms of the pattern of fatal landslides. This has continued through June, with the total number recorded in this month once again being lower than for both February and March. It is surprising that the June total is lower than that of May, as well. We would normally expect to see the monthly landslide total increasing from April through to July. This may indicate that patterns of rainfall this year are varying from the norm. More research is needed.

My preferred way of presenting this data us to use the cumulative total by pentad. This graph is to pentad 30, which captures all of the June data:-

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

The shows that the number of fatal landslides in 2026 continues to run way ahead of the long term mean, and within noise was equivalent to the exceptional year of 2024 (albeit with a different temporal pattern).

The end of June marks the start of the Northern Hemisphere monsoon season, and the uptick in the number of recorded landslides is clear in the graph. It will be interesting to see the July data as the monsoon gets into full swing.

I hope to be able to produce the July 2026 data next week.

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.

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In August of 2020, intense winds accompanied a severe thunderstorm that ripped through the Great Plains. Gusts up to 100 miles (160 kilometers) per hour produced 26 tornadoes, destroyed crops, took roofs off houses, knocked out power, and killed four people.

The storm was a derecho—a fast-moving, destructive windstorm that forms under unique conditions.

Radar shows the 10 August 2020 derecho at 1-hour time steps as it moved across the Plains and Midwest states. Credit: NOAA/NWS

Scientists track extreme weather phenomena like tornadoes, hurricanes, and derechos in detail to aid in forecasting and communication to the public. But definitions for derechos have always varied, and a comprehensive inventory of them had never existed, until now. A new study, published in the Bulletin of the American Meteorological Society, presents the country’s first archive of derechos, offering scientists a better opportunity to understand the drivers behind these destructive storms.

“We’re trying to objectively identify these events,” said Brian Squitieri, lead author of the new study and a meteorologist at NOAA’s Storm Prediction Center.

Assembling an Archive

“For a long time, meteorologists have taken the approach of ‘It’s hard to define a derecho, but I know one when I see one.’”

The definition of the term “derecho” has been difficult for scientists to pin down: “For a long time, meteorologists have taken the approach of ‘It’s hard to define a derecho, but I know one when I see one,’” said Michael Coniglio, a meteorologist at NOAA’s National Severe Storms Laboratory who was not involved in the new study.

In a 2025 paper, Squitieri and others put forth a new definition of the term that required a windstorm to meet strict requirements for wind gusts and develop from a “cold pool-driven mesoscale convective system” (MCS)—a specific type of thunderstorm cluster resulting from a collection of cold air.

Creating an archive of derechos required applying this new definition to past events. Squitieri ensured that the criteria focused on the distinct physical atmospheric processes that lead to a derecho, rather than “just any large-scale thunderstorm wind event,” he said.

With their criteria in hand, the research team analyzed 2 decades’ worth of detailed data from the Next Generation Weather Radar (NEXRAD) system, operated by the National Weather Service, the Federal Aviation Administration, and the U.S. Air Force. Within the NEXRAD data (1996–2025), they found 96 definitive derechos and 13 likely derechos.

Prior to the NEXRAD era, NOAA used hand-drawn paper maps to summarize radar data and collected storm reports in various formats. Squitieri and the research team combed through more than 2,000 paper maps and more than 22,500 storm reports to identify likely past derechos dating back to 1955. Still, without NEXRAD data, none of the likely derechos from 1955 to 1995 could fully fulfill the team’s criteria. Instead, they identified 48 likely derechos and 16 possible derechos.

“There have been lots of attempts at this over the years,” Coniglio said. The new study, he said, “is an incredibly detailed and thorough paper that I think is now the definitive piece of research that we have out there to know if something is a derecho or not.”

Derecho Behavior

From the new archive, the researchers were able to distinguish patterns in derecho behavior in the United States. The archive confirmed that derechos typically form in three corridors: the Midwest/Ohio Valley, the Northern Plains, and the Southern Plains.

The team also noticed the impressive impact of derechos in the data. “There are a lot of common factors that seem to stick out in reports [of derechos] that are a little bit more unique than what you see with a lot of other wind events,” Squitieri said.

In particular, the identified derechos had large, long-lasting effects on communities, sometimes being responsible for dozens of deaths or leaving towns without power for days. In many cases, derechos caused the worst power outages in a town’s or region’s history. “That’s quite a title for derechos to compete with, but some have achieved that,” Squitieri said.

Satellite imagery shows the 20 June 2025 derecho moving across North Dakota. Credit: CSU/CIRA & NOAA

Some written reports of derechos compared the destruction left in their wake to the effects of hurricanes. Squitieri emphasized that just because a certain windstorm doesn’t meet the derecho criteria doesn’t mean it’s not dangerous and that plenty of windstorms that are not derechos still have tremendous impacts.

Future Forecasts

The derecho archive is another step in NOAA’s goals of ultimately being able to better forecast derechos and better communicate derecho risk to the public. Scientists can use the archive to assess what conditions seem to be present for the formation of derechos compared to other wind events.

“We might be able to cue in on a clue for these higher-impact events more cleanly,” Squitieri said.

“Classifying these things ahead of time can help [meteorologists] understand what to look for and what to communicate to the public.”

The Storm Prediction Center has already begun to study the ambient environments that seem to create derechos to parse out signals that forecasters could use, with promising results, he added.

NOAA is also working to develop a MCS wind swath classification system similar to the Saffir-Simpson Hurricane Wind Scale to help forecasters communicate the risk of wind events to the public. This scale would classify all MCS wind swaths into two types: squall-line wind swaths and those driven by cold pools. Squitieri imagines that a 4 or 5 on the cold-pool-driven scale would be a derecho or “super derecho,” respectively, and lower numbers would be used to describe the risks posed by less severe storms. He hopes that such a scale would be operational sometime in 2027 or 2028.

“Classifying these things ahead of time can help [meteorologists] understand what to look for and what to communicate to the public,” Coniglio said.

—Grace van Deelen (@gvd.bsky.social), Staff Writer

Citation: van Deelen, G. (2026), What drives derechos? The first derecho archive could help meteorologists figure it out., Eos, 107, https://doi.org/10.1029/2026EO260245. Published on 28 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.

Source: Journal of Geophysical Research: Machine Learning and Computation

This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。

单个地震仪通常不足以可靠地探测地震或地下核试验等人类活动。因此，研究人员通常会结合分布在小范围地理区域内的多个地震仪的读数，来提高分析的可靠性。Köhler 等人的一项新研究表明，人工智能 (AI) 可以比传统技术更有效地整合来自多个传感器的读数，从而更可靠地探测微弱的地震信号。

研究人员利用挪威地震研究基金会 NORSAR和其他运营商运营的地震阵列 30 年的观测数据，并通过三种不同的方式训练了一个 AI 模型来探测地震信号。首先，他们每次使用一个台站的数据训练模型，然后应用该模型并将每个台站的结果合并。其次，他们使用传统技术合并同一阵列中多个传感器的信号，然后使用来自多个台站的这些合并信号训练模型。第三，他们将来自所有阵列台站的所有数据都提供给模型，让模型自行决定如何合并这些数据。

第二种方法（训练前合并信号）能够放大微弱信号，其信号检测精度在三种方法中最高。同时，第三种模型（由模型自行决定如何合并台站数据）是计算效率最高的策略，其精度介于其他两种方法之间。

考虑到需要在精度和速度之间取得平衡，研究人员建议在进行实时监测时由模型自行决定如何合并数据，而在可以接受较慢速度的情形中，可以在应用模型之前或之后合并数据。

然而，由于使用区域性有限的训练数据集，该模型对训练区域之外的区域泛化能力较差。若能使用全球数据进行训练，有望改进结果。这一问题主要出现在S波检测中，在P波检测的泛化能力方面则未出现类似问题。

总体而言，结果表明，人工智能可以通过帮助研究人员检测地震、地下核试验和其他地震活动中难以识别的微弱信号来提升地震监测能力。(Journal of Geophysical Research: Machine Learning and Computation, https://doi.org/10.1029/2026JH001249, 2026)

—科学撰稿人Saima May Sidik (@saimamay.bsky.social)

This translation was made by Wiley. 本文翻译由Wiley提供。

Read this article on WeChat. 在微信上分享本文。

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Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Journal of Geophysical Research: Solid Earth

Unlocking the physics of natural and induced earthquakes remains a major challenge. Gischig et al. [2026] performed the “Mzero” hydraulic stimulation experiments within the BedrettoLab, which aimed to find a stimulation procedure to enhance seismicity up to an induced moment magnitude (Mw) 0 earthquake. The multi-sensor network enabled detailed measurements of pressure, fluid flow, and deformation during the stimulations. Some experiments were conducted in a pre-conditioned rock mass, where fluids had previously been injected at pressures just below the fault reactivation threshold.

The results show that earthquake evolution, migration, and magnitude strongly depend on both the injection procedure and the site’s stimulation history. Pre-conditioning induced a mainshock-aftershock sequence and altered rock deformation and fluid flow patterns. In contrast, experiments without pre-conditioning produced no mainshock but exhibited higher seismicity rates and more pronounced outward migration of micro-earthquakes.

These findings are highly relevant for developing strategies to mitigate or even suppress injection-induced felt earthquakes in geo-energy applications.

Citation: Gischig, V. S., Meier, M.-A., Lambiase, A., Jiang, D., Hertrich, M., Gholizadeh Doonechaly, N., et al. (2026). Hydraulic stimulation experiments attempting to enhance induced seismicity for earthquake physics research. Journal of Geophysical Research: Solid Earth, 131, e2026JB033768. https://doi.org/10.1029/2026JB033768

—Birgit I. Mueller, Associate Editor, JGR: Solid Earth

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Satellite images show two very large landslides and multiple smaller failures, and channelised debris flows, in Shimen County in China.

In China, this year rainy season started with an intense event that covered the provinces of Guizhou, Hubei and Hunan in the period between 17 and 21 May 2026. There were some news reports at the time, although the story disappeared quite quickly. One area that was seriously affected was Enshi Tujia and Miao autonomous prefecture, which I have highlighted previously.

However, news reports also suggested a major impact in Shimen County in Hunan Province, which impacted 23 townships with 103,247 residents were affected. One news report indicates that about 340 mm of rain fell in 24 hours. There was some imagery of the aftermath of landslides. One article from Hong Kong reports 16 dead and missing in this area.

Planet Labs has now managed to capture some good imagery of the aftermath of the rainfall event in Shimen County. The area affected is around: [29.9428, 110.5510]. Planet Labs captured an image on 27 June 2026 using their PlanetScope instruments:-

Planet Labs image of the May 2026 landslides in Shimen County, China. Image copyright Planet Labs, used with permission, draped onto the Google Earth DEM.

There are two very large landslides in the image (and highlighted below). The one with the marker is about 3.5 km from the crown to the main drainage line, although one could argue that the runout distance is about another kilometre beyond that point. Note that the image shows that this landslide was valley-blocking and that a small lake has developed. There is a Sentinel image from 23 July 2026 that shows that this lake was still intact.

Planet Labs image of one of the May 2026 landslides in Shimen County, China. Image copyright Planet Labs, used with permission, draped onto the Google Earth DEM.

The other large landslide, also seen in the above image, is about 3 km long and 450 m wide. Elsewhere there are many smaller landslides, although some of these are over a kilometre in length:-

Planet Labs image of the smaller May 2026 landslides in Shimen County, China. Image copyright Planet Labs, used with permission, draped onto the Google Earth DEM.

It is notable that these landslides have generated very serious channelised debris flows in the main drainage lines, which appear to have extended over a distance of many kilometres. There is evidence of severe damage to the infrastructure in the channels.

This intense cluster of landslides occurs in an area of about 20 km x 7 km. Clearly, in this zone there must have been very exceptional rainfall, greater than in adjacent areas.

Acknowledgement

Many thanks to Planet Labs for use of the imagery.

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

It is always encouraging when a new study improves our understanding of a process or compartment within the global nitrogen (N) cycle. This is certainly the case of the recently published study by Langley et al. [2026].

Drawing on an extensive dataset comprising of 8,012 soil N measurements from 255 tidal wetlands, including both salt marshes and mangroves, the authors show that these ecosystems act as important sinks for nitrogen. This stored nitrogen, referred to as blue nitrogen, is buried alongside carbon in wetland soils (see figure above).

The study estimates that tidal wetlands account for approximately 13-15% of marine nitrogen burial, highlighting their role as major hotspots of N accumulation in coastal environments. By retaining nitrogen that would otherwise be transported to adjacent waters, these ecosystems help mitigate harmful environmental impacts such as eutrophication, toxic algal blooms, and water quality degradation.

However, the capacity of tidal wetlands to provide this valuable ecosystem service is increasingly threatened by human-driven environmental change. Rising sea levels may enhance nitrogen sequestration in some wetlands, but only where these ecosystems can persist. If wetlands are degraded or lost, the consequences could be severe. Rather than functioning as N sinks, they may become net sources of N, releasing previously stored N back into aquatic systems and exacerbating the very problems they currently help to alleviate. Thus, conserving and restoring tidal wetlands is essential, not only for blue carbon storage, but also for maintaining their critical role in regulating the coastal nitrogen cycle.  

Citation: Langley, J. A., Chapman, S. K., Wang, L., Maxwell, T. L., Rivera, P., Adame, M. F., et al. (2026). Blue nitrogen follows the fate of tidal wetlands. Earth’s Future, 14, e2025EF006747. https://doi.org/10.1029/2025EF006747

—Luis Lassaletta, Associate Editor, Earth’s Future

Text © 2026. The authors. CC BY-NC-ND 3.0
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Editors’ Vox is a blog from AGU’s Publications Department.

Sand and gravel mined from riverbeds serve as essential raw materials for concrete, asphalt, and other construction materials across the world. But the processes of extracting these critical natural resources have serious environmental and ecological consequences.

A new article in Reviews of Geophysics examines where and how much sand and gravel are mined across the world, and the environmental and societal impacts. Here, we asked the authors to give an overview of sand and gravel mining, the challenges of studying the impacts, and what questions remain.

What are the primary uses of river sand and gravel?

River sand and gravel are the most heavily mined solid materials globally.

River sand and gravel, collectively known as aggregates, are the most heavily mined solid materials globally, serving as the literal backbone of modern urban infrastructure and economic development. Their primary application is in the construction industry, where they constitute over 70% of concrete by volume, alongside applications in asphalt production and building foundations.

River sand is uniquely prized and irreplaceable for concrete manufacturing due to its distinct, naturally weathered properties. Unlike desert sand, which is too fine and rounded, river sand possesses sharp, angular grains that provide the critical granular friction and structural bonding required for robust concrete mixes. Additionally, it is entirely non-saline, making it far superior to marine sand, which contains salts that corrode steel reinforcement structures within buildings and bridges. Beyond concrete and asphalt, massive volumes of river sand are used directly for land reclamation projects to engineer new land space in coastal cities before major building construction begins.

Where are river sand and gravel mined across the world?

Globally, total demand for sand and gravel used in concrete production reached an estimated 28.03 billion tonnes in 2024, spanning at least 65 countries that we identified through our literature review. While sand and gravel mining (SGM) is a global phenomenon, extraction activities and consumption patterns are highly unevenly distributed, with dramatic hotspots concentrated in rapidly developing regions.

Asia stood as the dominant epicentral region for aggregate demand in 2023, consuming an estimated 23.02 billion tonnes annually, driven overwhelmingly by booming urbanization and infrastructure expansion. Within Asia, China is the world’s largest consumer by a wide margin, extracting 6.07 billion tonnes of sand and 8.10 billion tonnes of gravel in a single year to support its construction sector. India ranks as the second highest global consumer, where sand mining is heavily concentrated in peninsular rivers during the dry season and gravel extraction dominates the Himalayan foothills. Vietnam is the third largest consumer globally, with intense, mechanized dredging occurring throughout the Mekong and Red River deltas.

Outside Asia, substantial and rising riverine extraction pressures are documented across Africa, particularly in Egypt, Algeria, and Nigeria, and South America, especially along large tropical systems such as the Paraná and Tocantins rivers in Brazil. Conversely, in Europe and North America, contemporary aggregate extraction has largely shifted away from active riverbeds toward marine sources, floodplain quarries, and crushed rock.

What are the environmental and ecological consequences of SGM?

The environmental and ecological consequences of sand and gravel mining are severe, cascading from localized physical disruptions into widespread ecosystem degradation.

The environmental and ecological consequences of sand and gravel mining are severe, cascading from localized physical disruptions into widespread ecosystem degradation. Instream extraction directly excavates the riverbed, creating dredge pits and other erosional features, while the resulting sediment deficit can generate a “hungry water” effect when removal exceeds natural replenishment. This imbalance promotes further riverbed incision, downstream and upstream erosion, and severe bank instability that may induce seasonal riverbank collapse. In deltas, channel deepening can allow seawater wedges to migrate farther inland, resulting in salinity intrusion that damages agricultural land and compromises freshwater security. Furthermore, vertical incision alters surface water–groundwater interactions, lowers adjacent water tables, and may impair alluvial aquifer recharge. Water quality can also deteriorate as heavy machinery and suction dredging resuspend bottom sediments, producing turbidity plumes, reducing dissolved oxygen, and potentially remobilizing sequestered contaminants, heavy metals, and excess agricultural nutrients.

Ecologically, these physical changes cause immediate habitat destruction. Benthic and macroinvertebrate communities may be buried or displaced, while critical spawning grounds for gravel-dependent fish species are removed or degraded. Together, these stressors reduce habitat complexity, alter algal and aquatic communities, and can drive broader biodiversity loss, threatening vulnerable river-dependent species and the long-term structural resilience of major river systems.

Sand and gravel mining can trigger a cascade of river-system impacts, from channel incision, bank erosion, and altered sediment transport to degraded habitats, reduced water quality, and wider risks for ecosystems and river-dependent communities. Credit: Park et al. [2026], Figure 13

Why is it challenging to study the impacts of SGM?

Studying the impacts of SGM is exceptionally challenging due to deep data scarcities, institutional opacity, and the complex biophysical scales of river networks. A primary obstacle is the severe under-reporting and prevalence of illegal mining operations; official government statistics and company reports frequently miss the true scale of extraction, with measured physical volumes often doubling or tripling officially declared numbers. Furthermore, international trade data (like the UN Comtrade database) is plagued by contradictory records between importing and exporting nations, treating sand as a homogeneous commodity while masking its exact geographic origin. Methodologically, much of the intense extraction occurs underwater, hidden from public view. Tracking these changes requires expensive, logistically demanding, and highly technical bathymetric sonar surveys that must be maintained over years to isolate mining signatures from natural seasonal erosion or the impacts of upstream dams. Finally, there is a pronounced spatial-temporal mismatch. The socio-economic demand driving SGM often originates thousands of miles away in urban centers or across international borders, while the geomorphic and ecological impacts propagate dynamically both upstream and downstream, making it difficult to establish clear, direct cause-and-effect chains for policy design.

What is the “Driver-to-Management Pathway” framework?

The “Driver-to-Management Pathway for Sustainable Sand and Gravel Mining” (DMP-SGM) framework is a comprehensive, four-stage systemic structure introduced to unify the historically fragmented scientific understanding of global extraction activities. It serves as an analytical bridge linking macro-level economic forces to local biophysical changes and regulatory responses.

The first stage, Drivers, identifies and quantifies the socio-economic and demand-side pressures fueling extraction, such as rapid urbanization, industrial production, and land reclamation. The second stage, Extent, focuses on mapping the precise spatial distribution, temporal variations, and physical magnitudes of sediment removal. The third stage, Impact, systematically examines how these physical extraction footprints alter river systems, tracing the pathways through which hydrogeomorphic changes (such as riverbed incision, turbidity plumes, and bank collapse) cascade into downstream ecological degradation and socio-economic vulnerabilities. The final stage, Management, outlines governance interventions, emphasizing the need to integrate technical work—such as real-time vessel monitoring, numerical modeling, and the mapping of Sustainable Mining Zones (SMZs)—with adaptive top-down regulations, international cross-border policies, and inclusive stakeholder engagement. This framework closes the feedback loop, ensuring policy limits are directly informed by biophysical sediment replenishment rates.

The Driver-to-Management Pathway for Sustainable Sand and Gravel Mining links the forces driving extraction to its spatial extent, environmental and ecological impacts, and possible management responses. The framework highlights where better data, monitoring, and governance are needed to support more sustainable river sand and gravel mining. Credit: Park et al. [2026], Figure 2a

What are some of the remaining knowledge gaps?

Despite an accelerating volume of research, profound knowledge gaps remain where additional scientific efforts are critically needed to guide sustainable resource management. Geographically, research remains heavily clustered around a few high-profile hotspots such as in China and Vietnam, leaving emerging mining fronts across rapidly urbanizing regions of Africa and South America largely undocumented and limiting the global transferability of management strategies. Thematically, the literature is heavily dominated by physical hydrogeomorphic perspectives. Quantitative, empirical studies that measure the direct, long-term impacts of SGM on aquatic biodiversity, food security, human health, and local livelihoods remain rare and are frequently treated as secondary components rather than primary research foci. Mechanistically, the exact thresholds and baseline rates of natural sediment replenishment are poorly constrained for most global rivers, leaving policy makers unable to establish geomorphically sustainable extraction caps.

Furthermore, additional research is urgently required to standardize remote sensing detection algorithms that can accurately track small-scale, artisanal mining operations across diverse geographic regions. Finally, a critical gap exists in understanding the compound, non-linear interactions between SGM and other systemic anthropogeomorphic stressors, such as climate change, relative sea-level rise, land subsidence, and upstream sediment trapping by hydropower dams.

—Edward Park (geo.edpark@gmail.com; 0000-0002-1299-1724), Nanyang Technological University, Singapore; and Christopher Hackney (0000-0001-5390-9136), Newcastle University, United Kingdom

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: Park, E., and C. Hackney (2026), The hidden costs of mining river sand, Eos, 107, https://doi.org/10.1029/2026EO265027. Published on 27 July 2026. This article does not represent the opinion of AGU, Eos, or any of its affiliates. It is solely the opinion of the author(s). Text © 2026. The authors. CC BY-NC-ND 3.0
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Source: Earth and Space Science

The expansive red bluffs of Western Australia’s Yilgarn Craton give the landscape a Martian appearance. It turns out the resemblance is more than superficial: The Yilgarn Craton also shares geological characteristics with lakes in Mars’s Terra Sirenum region. Plattner et al. recently characterized those shared features to shed light on the region’s aqueous history and its potential to have supported life.

The Yilgarn Craton contains thousands of acidic and saline lakes that undergo repeated wet-dry cycles. The researchers sampled 40 lakes during both the wet and dry seasons to assess how they change through time. These extreme environments are shaped by the interplay of groundwater, evaporation, and surface processes, generating a remarkable diversity of geochemical conditions. The mineral fingerprints preserved across these landscapes record long-lived groundwater activity and recurring wet-dry cycles, offering clues to how similar water-rock interactions may have shaped potentially habitable environments on the Red Planet.

The geochemistry of lake beds varied widely in response to these hydrologic fluctuations, the researchers found. In some shallow lakes, salt was the predominant mineral that accumulated. In others, a wider variety of minerals, including aluminum-rich clays and iron oxides, built up over time. Acidity and salinity levels also varied.

Some Australian lakes show depositions similar to craters in the Terra Sirenum region on Mars, suggesting that similar hydrologic processes might have taken place over the planet’s history. In some cases, the findings contradict long-held notions that magmatism must have shaped portions of Mars’s surface.

Even though these combinations of salts and acidic minerals indicate extreme lake conditions, the lakes in Western Australia still support diverse microbial life, suggesting that Terra Sirenum might be one of the best places to look for evidence of potential life on Mars, the authors wrote. (Earth and Space Science, https://doi.org/10.1029/2026EA005066, 2026)

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

Citation: Sidik, S. M. (2026), What Australian lakes showed us about Martian hydrology, Eos, 107, https://doi.org/10.1029/2026EO260244. Published on [DAY MONTH] 2026. Text © 2026. AGU. CC BY-NC-ND 3.0
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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.

It’s well-documented that climate change is killing people.

A few months ago, the University of Chicago’s Climate Impact Lab released a report that found that, by 2050, about 10 times as many heat-related deaths would occur in poor countries as in richer ones.

Today, the same lab released a new report. This one found that the regions most affected by extreme heat are also the regions least likely to have increased levels of electricity to power the air conditioning that might provide relief. Use of cooling-related electricity is projected to grow seven times more in middle-income countries than in low-income countries in response to climate change.

“Air conditioning is a life saver, and climate change will no doubt lead to more AC adoption in today’s wealthy countries. Our research finds, however, that in too many countries around the world people will not be able to respond in the same way. The result is one of climate’s great cruelties—lots of death in the very countries that have contributed the least to climate change,” Michael Greenstone, a co-founder of the Climate Impact Lab, said in a statement.

 Related

•  Read the Report: Measuring the impact of rising temperatures on energy consumption to target adaptation planning
•  Major Investment in Air-Conditioning Needed to Address Future Heat Waves
•  Poor Countries Could Suffer 90% of all Heat-Related Deaths By 2050
 

The researchers describe “mortality cooling trap” areas, or locations where increased electricity consumption would most improve human welfare and save lives, but where such increases in consumption are not projected. The 18 identified countries are home to 676 million people, and about 377,000 people in these areas are projected to die each year beginning in 2050, thanks to the combination of hotter temperatures and low projected increases in energy consumption.

Most of the areas are in northern sub-Saharan Africa, in countries such as Burkina Faso, Chad, Mali, and Niger, with others in southern Asia, including Bangladesh, Myanmar, Nepal, and Pakistan.

This chart shows countries in the “mortality-cooling trap,” in decreasing order of the percentage of their population that live in mortality-cooling trap regions. Click to enlarge. Credit: Adaptation Roadmap: Energy, Climate Impact Lab, July 2026

The analysis accounted for deaths caused explicitly by heat, such as heat stroke, as well as related deaths, such as heat-related disease or cardiovascular stress, Genevieve Maricle, executive director of the Climate Impact Lab, said in an email to Eos.

Maricle told Eos that one of the most striking parts of the report to her was the differences in the death tolls between lower-income and higher-income countries, even when those countries have similar climates. For instance, Saudia Arabia faces high temperatures similar to those in Niger, but the projected increase in electricity use per person is approximately nine times higher in Saudia Arabia than Niger. The report found that by 2050, heat will claim 27,000 more lives per year in Niger than it will in Saudi Arabia.

“The disparity in projected deaths between regions is striking and lays bare how tightly climate resilience and energy are bound together,” Maricle wrote. “The communities facing the most extreme heat are also locked out of the cooling that could protect them – a deadly combination of maximum exposure and minimum defense.”

—Emily Gardner (@emfurd.bsky.social), Deputy 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
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A significant reactivation occurred over the weekend of the 22 January 2026 Mauao landslide in Tauranga.

Loyal readers will remember my posts on the Mauao landslide in Mount Maunganui in New Zealand on 22 January 2026, which killed six people. Over the weekend, heavy rainfall caused the landslide to reactivate. Fortunately, in this case there have been no fatalities.

1News has a video of the immediate aftermath of the landslide, shot by a local resident. It includes this still of the immediate aftermath:-

The aftermath of the reactivation of the Mauao landslide in New Zealand. Still from a video posted by 1News.

Meanwhile, Charlie Rahiri from Tauranga City Council has posted this video explaining the situation:-

Tauranga City Council reports that there have been three landslides in recent days at the Mauao landslide site. The head scarp has retrogressed about 20 metres and 8,000 m3 of material has moved over a maximum distance of about 100 metres.

It was an interesting choice to film the video directly at the foot of the debris given that the slope is considered to be unstable and the mass is, in the words of the council, “saturated, mobile and fluid“.

The rear scarp of the landslide remains steep and quite tall, so further reactivations of the Mauao landslide cannot be precluded. This is strong evidence that the situation remains very challenging, but also that New Zealand is well versed in terms of managing these risks.

Taranga City Council has an excellent webpage dedicated to updates regarding the Mount Mauao landslide.

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Source: Journal of Geophysical Research: Planets

Io—Jupiter’s third-largest moon—is constantly kneaded and deformed by the gravitational pull of Jupiter and two of its other moons, Europa and Ganymede. The resulting friction inside Io generates extreme internal heat, fueling volcanoes that erupt all over its surface. In fact, Io is more volcanically active than any other world in our solar system.

Nearly all prior observations of Io’s heat have relied on infrared measurements that could detect temperatures only at the moon’s very outermost “skin.” Now, Brown et al. have taken Io’s internal temperature for the first time.

The researchers used data captured by the Microwave Radiometer instrument aboard NASA’s Juno spacecraft—which has orbited Jupiter since 2016—during close flybys of Io in December 2023 and February 2024.

These data revealed Io’s thermal emissions at microwave wavelengths, which are longer than infrared, enabling the researchers to peer beneath the surface for tens of meters. Their analysis involved identifying and removing portions of the data representing reflections of the sky on the moon’s surface. The goal was to be left with observations truly representative of Io’s characteristics.

These observations showed that the upper tens of meters of Io’s surface are strongly heated by internal processes. Two possible explanations that fit the data are that heat may rise steadily through a conductive layer near the surface and that heat from recent lava flows or hot vents may escape to the surface through thin patches of cooling crust, with the latter being more likely on the basis of the existence of tall mountains.

Further analysis of the microwave observations revealed more about Io. The data suggest that Io has a relatively smooth surface, similar to Earth’s plains. They also suggest that Io has an upper layer with a lower density than solid rock, perhaps similar to volcanic ash or pumice, which likely lies atop denser material several meters below.

These findings and further analysis of Juno’s Microwave Radiometer data could lead to a deeper understanding of Io, particularly the mechanisms by which it loses internal heat and how heat flow patterns may differ across its surface. This work could also help to inform the design of microwave-detecting instrumentation for future missions to Io or other rocky and icy worlds. (Journal of Geophysical Research: Planets, https://doi.org/10.1029/2025JE009622, 2026)

—Sarah Stanley, Science Writer

Citation: Stanley, S. (2026), Io’s hidden heat revealed for the first time, Eos, 107, https://doi.org/10.1029/2026EO260234. Published on 24 July 2026. Text © 2026. AGU. CC BY-NC-ND 3.0
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Want updates from a trusted source about U.S. mining developments? Preference Eos in your searches! Go to Google

In April, President Donald Trump officially revoked a ban on mining that had protected more than 225,000 acres (91,054 hectares) of federal land in Minnesota’s Superior National Forest from mineral exploration and development.

“It’s official. The illegal mining ban put in place by former President Biden has been overturned indefinitely, ending a reckless policy that sidelined Minnesota’s miners and undermined our nation’s ability to source our own materials,” Rep. Pete Stauber (R-Minn.) said in a statement after the repeal.

The action stoked new public concern about two proposed mines near the Boundary Waters Canoe Area Wilderness, a remote, million-acre part of Superior National Forest peppered with interconnected lakes and streams. The NewRange Copper Nickel company’s NorthMet mine, a joint venture of PolyMet Mining Corporation and Teck Resources, would be located approximately 20 miles (32 kilometers) from Boundary Waters in the St. Louis River watershed, which drains into Lake Superior. The Twin Metals Minnesota mine, owned by the multinational mining company Antofagasta PLC, would be located even closer to Boundary Waters and within the Rainy River watershed, which ultimately drains into Lake of the Woods, a lake shared by the Canadian provinces of Ontario and Manitoba as well as Minnesota.

Trump’s repeal of the mining ban is just the latest step in a yearslong battle over the future of mining in northeastern Minnesota, which is a magnet for recreationists and mining companies alike because of a geologic past that created pristine lakes atop rich deposits of critical minerals.

A Rift in the Bedrock

The deposits targeted by NewRange and Twin Metals were formed as a result of a rifting event that took place in the Proterozoic eon, roughly a billion years ago, during which the North American continent was expanding and breaking apart, said Adam Simon, a geologist at the University of Michigan who studies mineral deposit formation. “You can literally think of it as a crack or unzipping of the crust.”

The rift ran from the northeastern corner of Lake Superior, through what is now southwestern Minnesota, and into current-day Iowa and Kansas. The separation of the continent reduced pressure on Earth’s interior, which allowed molten rock to rise from the mantle to just below the surface, and some even erupted at the surface as lava flows. Molten rock from Earth’s mantle contains high concentrations of metal sulfide minerals of interest to mining companies today, including copper, gold, silver, platinum, cobalt, nickel, and chromium.

The rifting event that formed the Duluth Complex stretched across the Great Lakes Region and created intrusions of magma (colored in red) rich in valuable minerals. Credit: Wikimedia Commons/USGS, Public Domain

This uplift of magma, followed by hundreds of millions of years of erosion from glaciers, eventually formed what geologists now know as the Duluth Complex, a roughly 100-mile-long (161-kilometer-long) area north of Duluth, Minn., rich in metal sulfides.

Sulfate Streams

Today, Minnesota is the “Land of 10,000 Lakes,” and many residents worry about the potential impacts of mining in the water-dominated landscape.

The main concern is sulfate, a by-product of the separation of metals from the sulfide minerals that encompass them. Mining companies typically try to contain sulfate by storing mining waste in underground pits and chemically treating water that has been used in mining processes, though mining is still a significant source of sulfate in natural waters.

Though sulfate itself is not harmful to wetland ecosystems, it can cause a range of ecological issues once it is chemically transformed, said Amy Myrbo, a geologist and environmental consultant in Minneapolis. Naturally occurring bacteria in lake bed mud transform sulfate to sulfide, which creates hydrogen sulfide, a substance harmful to plants, when dissolved. In Minnesota, wild rice is an edible wetland grass that serves as an important food source and sacred plant to Indigenous groups; it reacts poorly to water high in sulfide. Additionally, the process can make water browner, fuel algal blooms, and increase freshwater concentrations of a harmful, bioaccumulative form of mercury.

“It’s a really underappreciated contaminant.”

Sulfate is “a really underappreciated contaminant” in fresh water, she said.

Though mines themselves are prohibited within the Boundary Waters area, environmental advocates are concerned that sulfate pollution from mine waste could flow in the wilderness’s waterways. The Boundary Waters wilderness is particularly susceptible to the nutrient-increasing effects of sulfate because its lakes tend to have a high amount of organic matter in their sediments, Myrbo said. “If we get sulfate pollution there, it could really be a problem.”

Minnesota is the only state with a sulfate water quality standard, meant to protect waters used for wild rice production. That standard is one of the only measures keeping the two proposed mines from moving forward, as dozens of wild rice waters are located within watersheds where the two proposed mines would be located.

Controlling Mine Waste

Open-pit mines are common in Minnesota, where iron deposits can be found at very shallow depths. The NewRange mine, though not an iron mine, would also be open-pit.

The Twin Metals project, however, would be an underground mine. Mining this way “significantly reduces the surface environmental impact,” Simon said. “What they’re essentially doing is surgically removing the ore underground.”

Still, separating metals from sulfide minerals creates mining waste high in sulfate, a slurry-like substance called mine tailings. Twin Metals plans to control this waste by drying it and compacting it into a mound that will then be “reclaimed with native soil and vegetation,” a method called dry stacking.

NewRange Copper Nickel plans to store its tailings in an existing facility provided by a closed iron mine. The company states that its methods will “clean up water quality issues from legacy iron ore mining and processing, leading to net reductions in loading of mercury and sulfate in the St. Louis River.”

“If someone says they’re going to open a sulfide ore mine without environmental contamination, they’re saying, ‘We’re going to be the first ones to ever do this.’”

Environmental advocates doubt that either company has an infallible plan to contain its waste because of the track record of similar mining projects. For example, one report commissioned by Northeastern Minnesotans for Wilderness in 2025 reviewed eight hard-rock mines in the United States and found that all eight had degraded downstream water quality. A 2012 report from the environmental advocacy group Earthworks that reviewed 14 copper mines (representing 89% of U.S. copper production according to the most recent data at the time) found that each of the mines had experienced at least one spill or accidental release of mine waste.

“If someone says they’re going to open a sulfide ore mine without environmental contamination, they’re saying, ‘We’re going to be the first ones to ever do this,’” said Steve Emerman, a geologist and environmental consultant. Emerman advises the Friends of the Boundary Waters, an advocacy group, on the effects of mining on the wilderness area.

NewRange Copper Nickel and Twin Metals did not respond to requests for comment.

—Grace van Deelen (@gvd.bsky.social), Staff Writer

Citation: van Deelen, G. (2026), One billion years ago, northern Minnesota nearly split apart. Now, two companies want to mine the aftermath., Eos, 107, https://doi.org/10.1029/2026EO260239. Published on 24 July 2026. Text © 2025. AGU. CC BY-NC-ND 3.0
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body {background-color: #D2D1D5;} Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today.

23 July: This article was updated to include comments from Jennifer Jones and Colette Delawalla.

A report released this week directs the U.S. government to spark a “new golden age” of science by ushering funds toward artificial intelligence, fostering closer relationships with private industry, and dismantling and rebuilding the federal science funding process.

The report was written by Michael Kratsios, director of the White House Office of Science and Technology Policy. He outlined his recommendations to Congress at a hearing of the House Committee on Science, Space, and Technology on 22 July. 

Kratsios intended the report to emulate a letter written to President Franklin D. Roosevelt by Vannevar Bush in 1945, called Science, the Endless Frontier, which set the foundation for the current U.S. federal science process in which federal funds support university research. “As we celebrate the United States’ 250th anniversary, we have the responsibility to renew our foundations once more,” he wrote.

Kratsios listed four goals to guide this approach to U.S. science: to “prioritize the individual scientist over legacy institutions,” to “fundamentally change how research dollars are allocated, distributed, and assessed,” to “set clear scientific goals and build the industrial muscle to translate scientific discovery into technological strength,” and to “prepare our research enterprise for the AI revolution.”

“If you think about this report in the context of everything else this administration has done, it really is about weakening independence, weakening accountability, [and removing] scientific integrity protections in favor of empowering political appointees,” said Jennifer Jones, director of the Center for Science and Democracy at the Union of Concerned Scientists.

Science-A-New-Golden-Age_EosDownload

The report recommends a handful of federal priorities to achieve these goals, including the Genesis Mission, a “national effort to harness AI for scientific discovery at a scale no other nation can match” led by the Department of Energy (DOE).

At the 22 July hearing, Kratsios said the Genesis Mission “is the crown jewel of American AI for science” and announced that federal agencies have committed more than $5 billion to the project. So far, 278 awards have been made, the largest being a three-year, $60 million grant for a project that will “help deliver nuclear facilities faster and safer” with the use of AI, according to the DOE. 

“There’s no mention of scientific integrity, no mention of protections for independence, it’s just the opposite.”

“There are some examples in STEM where AI is valuable,” such as increasing power in computational modeling or identifying new Earth-like planets at scale, for example, wrote Colette Delawalla, founder of science advocacy group Stand Up for Science, in an email. “But AI will never replace curiosity-driven scientific advancement,” she wrote. 

Some scientists viewed the report as a way for the government to justify steering research funds toward private industry and increasing political interference in science. “I think they’re trying to turn it into a venture capital model,” Jeremy M. Berg, a computational biologist and former director of the National Institute of General Medical Sciences at the National Institutes of Health, told The New York Times. 

“Under the hood,” the report is a “vision for faster technology development and commercialization while underinvesting in the fundamental research, expert peer review, and scientific workforce that make those advances possible,” Keivan Stassun, an astrophysicist and member of the National Science Board prior to its dissolution by the Trump administration, told Science.

What’s interesting about the report, Jones said, is what it doesn’t mention. “There’s no mention of scientific integrity, no mention of protections for independence, it’s just the opposite,” she said. “There are no clear systems of accountability” explained in the report, and its suggestion to funnel funds to individual researchers rather than institutions such as universities also means more research could occur outside of universities’ established and robust systems of accountability, she added.

The recommendations in the document largely align with recommendations made by former National Academy of Sciences president Marcia McNutt in June. In the annual president’s address, McNutt encouraged the scientific community to “better understand the needs of industry” and embrace the use of AI to increase research efficiency. 

At the hearing, however, Kratsios agreed with Rep. Brian Babin (R-TX), chair of the committee, that the National Academies of Science, Engineering, and Medicine required more federal oversight, especially in light of its recent report on climate attribution science that Babin said raised “transparency concerns.” Kratsios said he looked forward to working with Congress to codify the recommendations made in the “new golden age” report.

Funding the Golden Age

The vision the report presents is accompanied by recommendations from Kratsios and Russell Vought, director of the Office of Management and Budget, for the FY 2028 budget. These recommendations include prioritizing funding for physical sciences, including quantum physics, chemistry and materials sciences, mathematics and computer sciences, engineering, and biological sciences. 

For FY 2028, “agencies should align their R&D investments, where appropriate, with the Administration’s national missions,” the report states, listing those “national missions” as AI, quantum computing, fusion power, the construction of a lunar base and return of humans to the Moon, autonomous robotics, and semiconductor technology. 

 
Related

•  Read the Report: “Science: A New Golden Age”
•  Watch the Hearing: “Examining the Priorities of the FY2027 Research and Technology Enterprise”
•  Trump’s Plan for Science: More Money for A.I., Less for Universities
•  Trump Administration Steers $5B Toward AI Research
•  Get Involved: AGU Science Policy Action Center
 

At the 22 July hearing, Democrats argued that the Trump administration’s actions have worked against the stated goals of Kratsios’s report. “Big new initiatives and promises mean nothing when agencies act capriciously, canceling grants midway, delaying awards for months, even after they’ve been selected through the rigorous merit review process, and blacklisting educational and research institutions,” said Rep. Zoe Lofgren (D-CA).

The report did not mention the Trump administration’s proposed FY 2027 budget, which, if finalized, would reduce the National Science Foundation’s budget by 53%, the U.S. Geological Survey’s budget by 37%, the NASA science budget by 42%, and NOAA’s budget by 28%.

“I anticipate the report will be used as the rationale for making further cuts in the budgets and staffing of federal research agencies while limiting their authority and accountability to the American people,” Neal Lane, former director of the NSF, told Science. 

The report also did not mention recent sweeping cuts to the NSF’s FY 2026 budget, the fact that the NSF currently has no director, or a June proposal from the Office of Management and Budget that, if finalized, would give political appointees final approval power for scientific grants.

—Grace van Deelen (@gvd.bsky.social), Staff Writer

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The winter earthquake of 923 or early 924 CE remains the benchmark event in the Seattle Fault Zone. It lifted shorelines around Puget Sound and gave geologists one of the most decisive records of the fault’s power.

But that shoreline-lifting earthquake is only part of the zone’s history. A recent Geological Society of America Bulletin study led by Stephen J. Angster, a geologist with the U.S. Geological Survey, looks past the most famous Seattle fault earthquake to examine evidence of earthquakes on lesser-known secondary faults.

At Lytle Beach on Bainbridge Island and at Vasa Park near Bellevue, subtle landforms and trench records suggest evidence of smaller ruptures has been preserved in the landscape but not fully recognized.

At Lytle Beach, the first clue was a small, raised surface. Angster described the “localized uplifted terrace” as “the first feature we saw that drew our eye to that area.” Similar features had already helped geologists read other secondary faults in the Seattle Fault Zone.

For instance, Angster said the Toe Jam Hill fault became one of the better-known examples when lidar helped reveal its scarp through dense vegetation. Later work found smaller uplifted terraces near similar secondary structures, which Angster said may indicate separate earthquake events focused on smaller faults rather than the larger regional rupture.

However, Lytle Beach stood out in a different way, as its fault dips south, in contrast to the zone’s better-known secondary faults, which dip north.

Faults Hidden in the Fold

Finding the localized uplifted terrace was only the beginning for Angster, who used lidar to uncover scarps and lineaments through the region’s forest cover.

His team also utilized ground-based magnetic transects across the Lytle Beach fault to look for changes that may reveal displacement beneath the surface. In addition, they gained a more direct view of disturbed sediments by excavating the Rose Hip trench across the newly identified Lytle Beach scarp and analyzing evidence from the earlier Vasa Park trench.

In the Rose Hip trench at Lytle Beach, Angster said the team found glacial deposits dating to roughly 15,000 years ago. Above them were lake sediments left behind as ice retreated. The trench also preserved an old layer of soil that formed after the lake dried. “That whole package was folded,” he said. “The only way you could fold those is mostly by a tectonic fault.”

A regional map of the Seattle Fault Zone shows the Lytle Beach and Vasa Park fault scarps, along with the uplifted shore platform associated with the 923 CE earthquake. A new study used mapping, geophysics, trenching, and dating methods to investigate secondary faults within the broader fault zone. Credit: Angster et al., 2026, https://doi.org/10.1130/B38333.1, CC-BY-4.0

The trench record showed evidence of two surface-rupturing earthquakes on the Lytle Beach fault. The older event occurred between 11,240 and 10,430 calibrated years before present, whereas the younger event occurred after 1663 CE, likely in the early nineteenth century. (“Calibrated years before present” refers to dates arrived at via radiocarbon dating, relative to the year 1950 as the “present.”)

“I thought the trenching on Lytle Beach was surprising, that we found two events, because it was such a relatively subtle feature that wasn’t really identified before,” Angster said.

At Vasa Park, the team found evidence of one past earthquake that occurred sometime between 11,380 and 7,400 calibrated years before present. That range overlaps with the older Lytle Beach event and raises the possibility of a longer rupture along the Blakely Harbor fault. However, the evidence in Angster’s study better supports separate ruptures on the two secondary faults.

A Longer Record of Smaller Ruptures

Harold Tobin, an earthquake scientist at the University of Washington who was not involved in the study, called the work “exciting new research.”

He said the study shows there is “room to accommodate smaller earthquakes” that do not reshape shorelines like the 923 or 924 event but are “still big enough to be damaging earthquakes.” The Angster paper, he said, examines “additional earthquakes not accounted for in the shoreline uplift record centered on the 923 or 924 event. These smaller earthquakes may have happened more recently or more often.”

“Subtle features, relatively small or fault traces that we might have ignored before, can be an important part of the story.”

For Tobin, the value also extends beyond Puget Sound. The study “shines a light for other people working in cities and urbanized settings,” he said, because it shows that “subtle features, relatively small or fault traces that we might have ignored before, can be an important part of the story.”

By comparing the dated events at Lytle Beach, Vasa Park, and other secondary faults, the authors estimated that these faults may have ruptured roughly every few hundred years during the late Holocene. Angster cautioned that it’s not quite clockwork. “The secondary faults appear, especially within the last 2,500 years, to rupture more frequently, and that’s where that 350-year interval comes from,” he said. But the estimate rests on a limited record.

Though the work doesn’t forecast the next earthquake, it gives scientists more of the past to weigh as they assess the Puget Lowland. Tobin said the paper “certainly beg[s] more research” because the Seattle Fault Zone contains many strands that still need to be studied. Earthquake hazards should remain “something real” for the public and civil planners.

“We don’t know when they are going to come,” Tobin said. “Obviously, we can go decades without any significant earthquakes, as we have since 2001. But when we least expect it, one will happen, and we just have to be prepared.”

Angster framed the findings more conservatively: “This study doesn’t really change the hazard with the Seattle Fault. It just provides more insight into how it behaves.”

—Jason Collins, Science Writer

Citation: Collins, J. (2026), Small faults add to Seattle’s quake story, Eos, 107, https://doi.org/10.1029/2026EO260238. Published on 23 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.

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.

What exactly is a moon? It’s an existential question lunar researchers found themselves pondering when they discovered an exosatellite at least 90% the size of Jupiter, orbiting a brown dwarf in a system about 73 light-years away from Earth.

 
Related

•  Read the Paper: Satellite Discovered Around a Star’s Substellar Companion
•  What Makes a Moon?
•  Very Large Telescope
 

Depending on how exactly one defines “moon,” the object could be the first moon definitively discovered outside our solar system.

If a moon is a body orbiting another body that is orbiting a star, then yes, we’ve got a moon on our hands. But this exosatellite is orbiting a brown dwarf, a body far larger than most planets but too small to sustain hydrogen fusion as stars do, instead of a planet. And it’s enormous in a way our local moons aren’t.

The whole system is really weird, explained lead author Kevin Hoy in an email to Eos. Hoy is a European Southern Observatory astrophysics Ph.D. student who is also affiliated with the Instituto de Estudios Astrofísicos at the Universidad Diego Portales in Chile and its Millennium Nucleus of Young Exoplanets and their Moons research center.

“The host star is much smaller than the Sun, the brown dwarf is much heavier than our most massive planet, and the satellite is much heavier than any of the moons in our system,” Hoy said. “No part of this system has an obvious comparison to any object in the Solar System.”

The researchers published their findings today in Nature.

When Words Fail

The scientists detected the maybe-moon in the CD-35 2722 system using the radial velocity method, which is often used to detect exoplanets. The brown dwarf moves slightly in response to the exosatellite’s orbit, as the exosatellite exerts a slight gravitational pull. These movements can be seen from Earth as small changes in the brown dwarf’s light spectrum. Scientists observed 26 of these changes from the European Southern Observatory’s Very Large Telescope (VLT) in Chile between October 2023 and February 2026.

The scientists ran several models to see what could explain the periodic changes, including a model in which the brown dwarf actually had two exosatellites. The best explanation to fit the data, they found, was one satellite at least 90% as massive as Jupiter orbiting the brown dwarf approximately every 170 days. (The brown dwarf itself is about 37 times as massive as Jupiter, meaning that although the proposed exomoon is huge, it could be proportionally much less massive compared to its primary than the Moon is to Earth.)

The combination of techniques the researchers used were first proposed for detecting exomoons in 2018, in a paper coauthored by Andrew Vanderburg, now an astronomer at Harvard University.

“I never would have imagined that this technique would reveal such an unusual object!” Vandenburg said in an email to Eos. He added that he wondered what exactly the exosatellite was, how it formed, and how big it was. “Regardless, it’s an amazing discovery and I’m super excited to see what else we can find by observing planets like this!”

Researchers have discovered more than 6,200 confirmed exoplanets so far, but only a few candidates for exomoons have been detected, and none have been confirmed. Such a discovery could help us learn more about how various parts of the universe were formed, and how they function today, the paper suggests.

Though it’s possible some unknown variable in the brown dwarf itself could be responsible for the periodic changes in radial velocity the team observed, “we can’t think of any physical mechanism that could reproduce the signal we see,” said Hoy, the lead author of the study. “That’s why we think a satellite is the most likely explanation.”

In this case, the scientists are confident about what they’ve found. They’re just not sure exactly what to call it.

“Perhaps we are approaching the limit of language invented to describe the Solar System, which is entirely unlike CD-35 2722,” the paper reads.

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

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

Protecting soil health is essential to achieving the United Nations Sustainable Development Goals (SDGs) since it has direct impacts on food and water security, ecosystem health, and socio-economic activities. However, human-induced drivers and pressures heighten the susceptibility of soils to degradation.

A new article in Reviews of Geophysics explores the drivers, impacts, and efforts to combat soil degradation. Here, we asked the authors to give an overview of soil degradation, practices being implemented to combat it, and what questions remain.

What is soil degradation and why is it important to study?

Soil degradation refers to the deterioration of soil quality resulting from unsustainable human activities most commonly associated with agricultural, pastoral, industrial, and urban land use. It involves a dynamic reduction in the physical, chemical, and biological properties of soil that diminishes its structural integrity, functional capacity, and overall resilience over time.

Studying soil degradation is important because it is a major global environmental challenge that threatens soil security, ecosystem services, agricultural productivity, and human well-being. It also makes land more susceptible to droughts, floods, landslides, and climate extremes. Soil degradation often develops gradually and may remain unnoticed until critical thresholds are reached, after which recovery can be extremely slow, costly, or even impossible. Understanding the causes, processes, and consequences of soil degradation is therefore essential for preventing long-term environmental and socio-economic damage and for supporting sustainable land management and ecosystem resilience.

What are the key processes that degrade soil?

The key processes of soil degradation can be grouped into physical, chemical, and biological degradation. Physical degradation includes the breakdown of soil structure, aggregate loss, compaction, reduced porosity and pore connectivity, and erosion caused by water, wind, tillage, or crop harvesting. These processes remove topsoil, nutrients, and organic matter while reducing the capacity of soil to retain water. Chemical degradation includes acidification, alkalization, nutrient depletion or excess nutrient accumulation, loss of soil organic matter and soil organic carbon, salinization, sodicity, and contamination by toxic chemicals or pollutants. Biological degradation involves declines in soil biodiversity, microbial activity, and overall biological functioning. These processes rarely occur independently; rather, they interact and reinforce each other thus increasing the susceptibility of soil to further degradation.

What are the major drivers of soil degradation and how do they differ from perturbations?

The major drivers of soil degradation are long-term natural or anthropogenic forces that initiate or accelerate the physical, chemical, and biological processes of soil degradation. These include deforestation, unsustainable agricultural practices, land-use change, industrial and mining activities, climate change, and overgrazing. These drivers place continuous pressure on the environment and gradually reduce soil functioning. In contrast, perturbations are typically short-term disturbances such as floods, droughts, extreme weather events, wildfires, or sudden land-use changes that temporarily disrupt soil ecosystems and their resilience. The distinction between drivers and perturbations lies primarily in their duration and persistence. When disturbances occur repeatedly or continue over long periods, they can become long-term drivers of degradation.

Drivers and pressures contributing to soil degradation, indicating the complex socio‐economic and environmental interactions that contribute. Credit: Shokri et al. [2026], Figure 1

How do scientists measure soil degradation at different spatial scales?

Scientists quantify soil degradation using complementary approaches across multiple spatial scales. At local or field scales, direct surveys and monitoring quantify physical, chemical, and biological indicators of soil health and degradation. These measurements are supported by expert assessments and land-user knowledge gathered from interviews or questionnaires. Analytical frameworks then combine these indicators to evaluate soil functions and ecosystem services under different land management practices. While field observations provide detailed and localized evidence, they are difficult to scale, require repeated monitoring, and depend on context-specific indicator thresholds.

At regional, national, continental, and global scales, assessments combine bottom-up, top-down, and hybrid methods including expert mapping, soil sampling, modeling, and remote sensing. High-resolution satellite imagery and remote sensing technologies enable continuous, large-scale monitoring of land cover, vegetation dynamics, erosion, soil moisture, and other indicators associated with soil degradation. These assessments are increasingly supported by big data analytics, high-performance computing, and advanced machine learning models that integrate diverse datasets and improve the detection and prediction of degradation patterns.

At the microscopic scale, a wide range of experimental and modeling techniques can be employed to characterize the parameters and processes governing the physical, chemical, and biological properties of soils, thereby providing insights into the mechanisms that contribute to soil degradation.

What are some of the restoration efforts or practices being implemented to combat soil degradation?

Efforts to restore degraded soils range from large-scale policy initiatives to practical land management strategies. At the national level, restoration projects such as China’s rehabilitation program on the Loess Plateau have successfully restored millions of hectares of degraded land. In Europe, international agreements to reduce transboundary air pollution have decreased acid deposition and promoted the recovery of acidified soils.

Global distribution of improved land management and restoration measures as applied in restoration scenarios (van der Esch et al., 2021). Credit: Shokri et al. [2026], Figure 4a

At the field scale, restoration focuses on minimizing further degradation while rebuilding soil health. Reducing vehicle traffic is encouraged to minimize soil disturbance and prevent compaction. Agricultural practices include reduced or no-tillage farming, crop rotation, agroforestry, cover crops, compost and manure application, integrated pest management, and efficient irrigation methods such as drip irrigation and rainwater harvesting. These practices improve soil structure, enhance soil fertility, reduce erosion, increase organic matter, and strengthen the long-term resilience of agricultural soils while supporting sustainable land management.

Why is combating soil degradation essential for achieving the United Nations Sustainable Development Goals?

Combating soil degradation is recognized as a fundamental prerequisite for achieving the United Nations Sustainable Development Goals (SDGs) due to the extensive socio-economic and ecological impacts of soil health. Healthy soils provide natural capital and ecosystem service delivery that directly support human well-being. Preventing soil degradation is essential for ensuring global food security, maintaining agricultural productivity, supporting livelihoods, and reducing hunger and poverty. Furthermore, maintaining soil functionality is strictly necessary for preserving water security, regulating the climate, and supporting overall ecosystem health. Consequently, sustainable soil management contributes directly to several SDGs, including SDG 2 (Zero Hunger), SDG 6 (Clean Water and Sanitation), SDG 13 (Climate Action), and SDG 15 (Life on Land). Failure to combat soil degradation can lead to severe socio-economic consequences such as health crises driven by desert dust storms and widespread human migration, which would completely undermine the environmental resilience demanded by the SDGs.

What are the remaining questions or knowledge gaps where additional research is needed?

Several important knowledge gaps remain in our understanding of soil degradation. One major challenge is the lack of a universally accepted definition of soil degradation. This inconsistency makes it difficult to compare studies and establish standardized indicators and assessment methods. In addition, many global and national assessments are fragmented, outdated, or lack long-term monitoring data.

Global climate simulations help scientists understand how the atmosphere, oceans, and land interact. These high-resolution models improve our ability to study environmental processes and assess how climate may influence soil degradation and ecosystem health. Credit: Shokri et al. [2026], Figure 31

Further research is needed to improve understanding of how multiple drivers interact, how quickly degradation develops, and whether soils can fully recover after pressures are removed. Scientists also need a better understanding of the links between climate, land use, and soil processes, as well as the socio-economic impacts on livelihoods, inequality, and migration. Improving monitoring methods, data sharing, and standardized protocols will help produce more reliable assessments and support more effective soil management and restoration strategies.

—Nima Shokri (nima.shokri@tuhh.de, 0000-0001-6799-4888), Institute of Geo-Hydroinformatics, Hamburg University of Technology, Germany; Mehdi Afshar (0000-0002-4411-3299), Institute of Geo-Hydroinformatics, Hamburg University of Technology, Germany; and Milad Aminzadeh (0000-0002-0074-3600), Institute of Geo-Hydroinformatics, Hamburg University of Technology, Germany

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: Shokri, N., M. Afshar, and M. Aminzadeh (2026), Why healthy soils matter more than ever, Eos, 107, https://doi.org/10.1029/2026EO265026. Published on 22 July 2026. This article does not represent the opinion of AGU, Eos, or any of its affiliates. It is solely the opinion of the author(s). Text © 2026. The authors. CC BY-NC-ND 3.0
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Stomach-churning dips and swerves can be the most unpleasant—and dangerous—part of flying. To travelers’ chagrin, climate change has already begun to make such aircraft turbulence more common, as it alters the movement of air masses at the heights where planes fly.

Researchers wondered whether stratospheric aerosol injection (SAI), a controversial climate intervention strategy to cool the planet by injecting sunlight-blocking aerosols into the stratosphere, could help. In a study published last month in Environmental Research Letters, a team modeled aircraft turbulence under future climates with and without SAI. The researchers found that climate intervention could, indeed, reduce aircraft turbulence, even below modern-day levels.

“SAI is very important, but on the other hand, it’s very dangerous,” said study author Hye-Yeong Chun, an atmospheric scientist at Yonsei University in Seoul, South Korea. “These results show that aviation turbulence is quite significantly reduced [with SAI]—so this is one merit, at least, on the SAI side.”

A Bumpy Future

Climate change isn’t warming the planet evenly; the poles are heating up faster than the equator. This imbalance shrinks the temperature difference between the rising masses of cool and warm air that meet to form the jet stream, a fast-moving current of air that swirls like a river around the globe near 9,100 meters (30,000 feet) in elevation. The lower temperature difference weakens the jet stream, making it wavier and prone to wind shear, or changes in wind speed or direction over short distances. Because wind shear is one of the primary causes of aircraft turbulence, plane rides are getting bumpier, explained Chun.

“[Turbulence is] a very intermittent and localized phenomenon. Even current weather forecasting models and high-resolution numerical models cannot directly predict turbulence.”

But turbulence is also one of the trickiest weather elements to predict, she said. Unlike turbulence from storms or clouds, which is visible and easier to forecast, so-called clear-air turbulence can’t be seen by pilots. “It’s a very intermittent and localized phenomenon,” said Chun. “Even current weather forecasting models and high-resolution numerical models cannot directly predict turbulence.”

Understanding turbulence and how the jet stream is changing is important “not only for comforting people, but also for reduction of greenhouse emissions,” said Tommaso Alberti, a physicist at Italy’s Istituto Nazionale di Geofisica e Vulcanologia who was not involved with the study. Turbulence can increase a plane’s fuel requirements as it readjusts, while taking advantage of a strong jet stream can shrink flight times and associated carbon emissions.

Since the phenomenon can’t be directly predicted, scientists like Chun use proxies—other measurements that indicate potential regions where turbulence might occur. In the new study, she and her colleagues used a measure called the Ellrod index, which combines data on vertical wind shear and the stretchiness of masses of air.

The researchers modeled how the Ellrod index would change across seven climate futures with varying amounts of greenhouse gas emissions, three of which had no human intervention and four of which had SAI. They found that although climate change should increase aircraft turbulence across nearly all latitudes, SAI could reduce such increases by up to 60%. And to Chun’s surprise, SAI was powerful enough not only to counteract future turbulence but also to reverse modern-day levels of climate-driven turbulence. One possible explanation is that depending on where the aerosols get injected, SAI cools the tropics more strongly than the poles, counteracting the shrinking temperature difference that forces the jet stream out of balance.

Global Tactics, Global Implications

“We have to find the optimal way to reduce temperature but, on the other hand, reduce any potential side effects.”

Though the study results are promising, they are far from a green light to conduct climate intervention, said Chun. Still, the goal set forth in the Paris Agreement of limiting global warming to 2°C above preindustrial levels will not be easy to achieve, she said. “We have to find the optimal way to reduce temperature but, on the other hand, reduce any potential side effects.”

With global climate interventions such as SAI, a top concern is that any side effects will occur throughout the world, ranging from changes in rainfall to disruptions to the ozone layer. The most commonly proposed aerosol, sulfur dioxide, can also cause acid rain as it falls out of the atmosphere.

Ramalingam Saravanan, an atmospheric scientist at Texas A&M University who was not involved with the study, said that researching SAI in “controlled and safe conditions” had its merits. But as a longtime modeler, he said, “There are all kinds of errors in models that we are still working with…saying ‘This is what will happen’ in a model may not exactly be what will happen in the real world.”

In turn, Saravanan worried that private individuals or companies pushing to enact climate intervention might overstate the benefits to airplane turbulence. “Focusing on potential modest benefits of a radical and uncertain mitigation approach, as this study does, risks deflecting attention away from the inherently large dangers of climate intervention,” he clarified in an email.

Alberti noted that artificial intelligence models may eventually be able to forecast clear-air turbulence, providing a less risky solution for dealing with the hazard. However, he noted that would only be a way to adapt to climate-driven turbulence, not mitigate it.

Chun said that she was not yet advocating for the actual implementation of SAI but that researching it is critical if global leaders are to consider such a strategy. AGU’s Ethical Framework Principles for Climate Intervention Research acknowledges that such geoengineering approaches shouldn’t move forward without an internationally agreed-upon ethical governance structure but states that “more knowledge about climate intervention approaches and their consequences will help society make informed, just decisions about the deployment of climate intervention.”

“The risk is quite significant,” Chun said. “Scientists have to work very hard to save lives, to save our planet.”

—Hannah Richter (@hannah-richter.bsky.social), Science Writer

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Citation: Richter, H. (2026), Stratospheric aerosol injection might make flights smoother, Eos, 107, https://doi.org/10.1029/2026EO260237. Published on 22 July 2026. Text © 2026. The authors. CC BY-NC-ND 3.0
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Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Community Science

California is experiencing major changes in how farmland is used as recent policies seek to protect groundwater resources. These changes are reshaping both the landscape and the lives of rural residents, especially in communities like Fairmead in Madera County, which is surrounded by water-intensive almond orchards.

In Community Science’s special collection on Transdisciplinary Collaboration for Sustainable Agriculture, Katrak-Adefowora et al. [2026] describe a project that engaged Fairmead residents and farmers in redesigning a small almond farm into a landscape that reflects multiple community priorities. The new landscape includes a basin that captures stormwater to reduce flooding and help replenish groundwater, native plants that improve habitat, and a walking path for community recreational use. Community members and farmers were engaged through workshops, outreach, and educational activities, with the project team remaining flexible and responsive to local input.

This paper shows how involving communities in landscape decisions from the beginning can lead to solutions that are both environmentally beneficial and responsive to local priorities. It also offers a practical collaborative model for other regions facing similar land-use and water challenges, demonstrating how partnerships among residents, farmers, nonprofits, businesses, local governments, and scientists can support more resilient communities.

Citation: Katrak-Adefowora, R., Massell, A., Ortiz, V., Vizcarra, A., Nelson, B., & Fernandez-Bou, A. S. (2026). Community-driven solutions for groundwater resilience in California. Community Science,5, e2025CSJ000167. https://doi.org/10.1029/2025CSJ000167

—Claire F. Beveridge, Editor, Community Science Exchange

Text © 2026. The authors. CC BY-NC-ND 3.0
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