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Satellite radar shows ground rising beneath the part of Aral Sea that has dried up

Phys.org: Earth science - Tue, 04/08/2025 - 14:00
A team of Earth scientists affiliated with Peking University and the Southern University of Science and Technology, both in China, and a researcher from the University of Southern California, in the U.S., have found that the land below parts of the Aral Sea that have dried up over the past several decades is slowly rising.

An Atmospheric River Exacerbated Türkiye’s 2023 Earthquake Crisis

EOS - Tue, 04/08/2025 - 13:53

On 6 February 2023, a pair of powerful earthquakes—magnitudes 7.8 and 7.5—struck southern Türkiye and northwestern Syria 9 hours apart, killing 59,000 people and causing catastrophic damage.

While in the area mapping earthquake-triggered landslides the following month, Istanbul Technical University geomorphologist Tolga Görüm and his team noticed an atmospheric river approaching the disaster zone. They found this worrying, because an earthquake can weaken surrounding slopes for months and possibly years, making them vulnerable to heavy rainfall.

In a recent Communications Earth & Environment study, Görüm and colleagues documented the atmospheric river’s characteristics and how it caused flooding, landslides, and, tragically, further loss of life in the already devastated region. According to the team, the case study demonstrates a need for updated hazard models that better integrate various atmospheric and seismic hazards, particularly as climate change is expected to intensify atmospheric rivers in some regions.

A Once-in-20-Year Storm

“This was the heaviest rainfall event in the area in the last 20 years.”

For the study, the scientists analyzed global climate data from the European Centre for Medium-Range Weather Forecasts’ Reanalysis v5 (ERA5). The data revealed that the atmospheric river, originating over the Red Sea, carried more moisture than did 99.99% of all such events recorded in the region. When that moisture hit southern Türkiye’s Taurus Mountains on 14 and 15 March 2023, the resulting upward airflow along the slopes produced extreme rainfall.

“This was the heaviest rainfall event in the area in the last 20 years,” Görüm said. In the Turkish town of Tut, the storm delivered up to 183 millimeters (7.2 inches) of rain within 20 hours. In addition, warm temperatures had caused snowmelt in the mountains just before the atmospheric river arrived, leaving the soil saturated with water and further reducing its stability.

By analyzing the strength of shaking, the steepness of the terrain, and the position of the slopes, the scientists estimated that the shear strength of hillsides—the ability of soil and rock to resist sliding when subjected to a force—in the Tut region was weakened by 52%–77%.

An atmospheric river hit the town of Tut 36 days after two powerful earthquakes, initiating catastrophic landslides. Credit: Tolga Görüm

The consequences were severe. “The atmospheric river hit the area, triggered significant sediment movement, and killed more than 20 people,” Görüm said. Twelve of those deaths were within the study area. The resulting landslides, debris flows, and flooding also disrupted ongoing recovery efforts from the earthquake.

The catastrophe was the result of unfortunate timing. Using a computational model, the scientists ran simulations for earthquakes occurring in different seasons and tracked landslide probability over 5 years. They found that had the earthquakes occurred during summer or fall instead of winter, the recovery period wouldn’t have coincided with peak atmospheric river season, and the landslide hazard would have been significantly reduced.

Ben Leshchinsky, a civil engineer at Oregon State University who has studied cascading hazards but wasn’t involved in the research, said this study “highlights the importance of remembering there is a legacy to hazards. It’s incredibly important to keep following what happens so we can make sure we recover more quickly and plan for recovery in a smarter, more resilient way.”

Anticipating the Worst

Preparing for contemporaneous disasters might become increasingly relevant. Using 40 years of data, the researchers showed that Türkiye has experienced a significant increase in atmospheric river frequency and intensity, likely driven by climate change.

The landslides and flooding that followed the atmospheric river in the earthquake-struck zone damaged roads and bridges, inhibiting recovery efforts. Credit: Tolga Görüm

This trend extends beyond Türkiye to other seismically active regions worldwide. “On the Pacific coast [of the United States], the frequency and magnitude of atmospheric rivers is even higher than our area,” Görüm noted, adding that Southern California is seismically similar to Türkiye. These parallels suggest that lessons learned from Türkiye’s experience could help vulnerable communities around the globe develop more comprehensive disaster preparedness plans.

“This paper…reinforces the argument that we need to be thinking about these coincident hazards.”

Bruce Malamud, a geophysicist at Durham University who wasn’t involved in the study, noted that it can be dangerous when multiple hazards coincide, because government agencies focusing on different hazards work independently, so their disaster responses aren’t coordinated. “What’s important about this paper is that it reinforces the argument that we need to be thinking about these coincident hazards,” he said.

Having spent time in the disaster zone following the 2023 earthquakes, Görüm saw damaged cities and the struggles of response crews to rescue people; he understands more than most the need to warn communities of additional hazards. “It was like a nightmare,” he said.

It’s taxing to work in those conditions, he said, “but at the same time it’s quite important. You have to learn from this type of event.”

—Andrew Chapman (@andrewchapman.bsky.social), Science Writer

Citation: Chapman, A. (2025), An atmospheric river exacerbated Türkiye’s 2023 earthquake crisis, Eos, 106, https://doi.org/10.1029/2025EO250132. Published on 8 April 2025. Text © 2025. 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.

Strange Branching of Water Flows Through Rivers and Lakes

EOS - Tue, 04/08/2025 - 12:00
Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Water Resources Research

Rivers can split into branches, a phenomenon called bifurcation. Typically, the branches return again to the main river or the same floodplain after some distance downstream from the bifurcation, such as around an island, in a braided river, or in a river delta. Some bifurcations, however, are different, branching off and never returning, and seemingly defying conventions of hydrology, the science of Earth’s water and especially its movement in relation to land.

In their new article, Sowby and Siegel [2025] describe such curious bifurcations of rivers and lakes in North and South America. Some rivers diverge rather than converge; some rivers flow in two directions; some lakes have not one but two outlets; and some watersheds have strange boundaries. Some of these irregular water bodies are remote and wild while others are developed and controlled; some are streams small enough to step over and others are lakes over 100 kilometers long; and some are protected in national parks, but others are not. Their irregularities illustrate various aspects and manifestations of the complexity of Earth’s water system on land and how much we have still to learn about it.

These irregularities raise interesting questions: How should the watershed boundaries of such water bodies be defined on maps? Whose water is it before or after it bifurcates? If contaminated, who is responsible? Should flows in a bifurcated river be manually controlled, or left to nature? How can such interesting hydrological features be preserved and studied? The authors explore the natural settings and the societal uses, impacts, and management of these unusual bodies of water on land, along with the implications for our ability to quantitatively model and predict their characteristics and involved water system interactions.

Citation: Sowby, R. B., & Siegel, A. C. (2025). Unusual drainages of the Americas. Water Resources Research, 61, e2024WR039824. https://doi.org/10.1029/2024WR039824

—Georgia Destouni, Editor-in-Chief, Water Resources Research

Text © 2024. 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.

Randomization of a laser wave front by the turbulent gas-puff $Z$-pinch plasma column

Physical Review E (Plasma physics) - Tue, 04/08/2025 - 10:00

Author(s): A. Rososhek, E. S. Lavine, B. R. Kusse, W. M. Potter, and D. A. Hammer

In this paper, we present the first direct experimental evidence supported by numerical modeling of a turbulent plasma column formed during a gas-puff z-pinch implosion generated by the cobra current. Utilizing an imaging refractometer, we showed a significant decrease in spatial autocorrelation of …


[Phys. Rev. E 111, 045202] Published Tue Apr 08, 2025

Coherent puff and slugs in transitional drift-wave turbulence

Physical Review E (Plasma physics) - Tue, 04/08/2025 - 10:00

Author(s): P. Manz, S. Knauer, C. Moon, N. Fahrenkamp, D. Di Matteo, and A. Fujisawa

The long-term development of the transitional regime of drift-wave turbulence is studied in a magnetized plasma column by means of the conditional-average technique. In the transitional regime, small changes in the magnetic-field strength as control parameter lead to large changes in the correlation…


[Phys. Rev. E 111, 045203] Published Tue Apr 08, 2025

Mercury concentrations in tree rings may enable trees to be 'witnesses' of illegal gold mining activities in the Amazon

Phys.org: Earth science - Tue, 04/08/2025 - 04:00
For hundreds of years, the Amazon has been exploited for its gold. Today, the precious metal is just as sought after, but the remaining tiny gold particles are much harder to find. Mining often happens in artisanal and small-scale mining operations that release mercury (Hg) into the air, polluting the environment and harming human health.

Fault identification, complexity and evolution of the 2021, Atarfe-Santa Fe earthquake swarm (Granada basin, Spain)

Geophysical Journal International - Tue, 04/08/2025 - 00:00
SummarySeismic swarms are known to occur in regions with complex deformation and multiple fault systems. The identification of the affected faults, the evolution of the seismicity and the rupture characteristics are key to understand seismotectonics and seismic hazard of such areas. We here address the Atarfe-Santa Fe earthquake swarm with > 5000 events, including six magnitude 4+ earthquakes, recorded in 2021 in the Granada Basin area (S-Spain). We use continuous data from a dense local recording network and apply deep learning models to pick and associate seismic phase arrivals and construct an automatic event catalogue. A double difference relocation of 3196 earthquakes reveals the seismotectonic fine-structure of the swarm. We identify planar, southwest-dipping structures among the relocated hypocentres, consistent with the NW-SE trending, high-angle normal faults present in this sector of the Granada basin. Earthquakes concentrate between 4-7 km depth along three different lineaments. The distinctive pattern of three equidistant, parallel segments allows an association of the swarm with the Ermita los Tres Juanes, Atarfe and Pinos Puente normal faults. These faults outcrop at the upward extrapolation of the swarm, forming an arrangement of three structures that mimic the geometry of the relocated seismicity at depth. In the course of the swarm, the seismicity jumped from the Ermita los Tres Juanes to the Atarfe fault, in midst of a rapid succession of three magnitude 4 earthquakes within 20 minutes, then migrated laterally along both faults, and later migrated basinwards to the Pinos Puente fault, which produced fewer and smaller events. We estimate apparent source time functions for five earthquakes (Mw 4.1 to 4.4) through the deconvolution of empirical Green's functions from the records, suggesting rupture propagation towards NW, N and E directions. An isochrone back projection of apparent source time functions suggests km-scale ruptures with simple slip distributions, showing lateral and updip components of rupture. Our results shed light on the complexity of this seismic swarm in terms of the fault network involved, the propagation of seismicity across the faults and the variable directions of individual ruptures.

The effect of photoelectron interhemispheric transport on ion temperature in the topside ionosphere around sunset

Publication date: Available online 1 April 2025

Source: Advances in Space Research

Author(s): Zhenzhang Tang, Huijun Le, Libo Liu, Yiding Chen, Ruilong Zhang

Identification of the structural configuration of the Equatorial Atlantic Ridge from satellite-derived gravity data using the enhancement techniques

Publication date: Available online 31 March 2025

Source: Advances in Space Research

Author(s): Luan Thanh Pham, Franck Eitel Kemgang Ghomsi, Ahmed M. Eldosouky

Nanosatellite Differential Drag Control for Variable Size Triangular Formation Flying

Publication date: Available online 31 March 2025

Source: Advances in Space Research

Author(s): Yaroslav Mashtakov, Uliana Monakhova, Danil Ivanov

Multiscale Periodic Analysis of Sunspot Number Data and F10.7 Index

Publication date: Available online 31 March 2025

Source: Advances in Space Research

Author(s): Yi Shen, Chunmei Zhao, Peicheng Li, Mengjun Hu, Bingbing Zhang, Wang Li

A Novel Snow Depth Estimation Model for the Eastern Himalayas Using DInSAR

Publication date: Available online 29 March 2025

Source: Advances in Space Research

Author(s): Manmit Kumar Singh, Ritu Anilkumar, Rishikesh Bharti

Chaotic encryption algorithm for satellite images based on novel RNA coding

Publication date: Available online 28 March 2025

Source: Advances in Space Research

Author(s): Chaofeng Zhao, Xinchao He, Yanfei Li, Bo Zeng

Transforming Soil Quality Index Predictions in the Nile River Basin Using Hybrid Stacking Machine Learning Techniques

Publication date: Available online 28 March 2025

Source: Advances in Space Research

Author(s): Chiranjit Singha, Satiprasad Sahoo, Ajit Govind

High-precision estimation of meteor radio echo angle of arrival over long antenna baselines under strong phase ambiguity

Publication date: Available online 27 March 2025

Source: Advances in Space Research

Author(s): Dmitry Korotyshkin

Precise real-time navigation of the LEO satellite enhanced by BDS-3 PPP-B2b service

Publication date: Available online 26 March 2025

Source: Advances in Space Research

Author(s): Xuewen Gong, Wanwei Zhang, Aili Zhao, Shuaihe Gao, Fuhong Wang, Jingkui Zhang, Song Xie, Guodong Feng, Zaichun Yang

Characteristics of tethered towing system after net capture

Publication date: Available online 26 March 2025

Source: Advances in Space Research

Author(s): Jia Guo, Zhaojun Pang, Weiliang Zhu, Jiyue Si, Zhonghua Du

An SPH model reconstruction framework with fragment mapping method for multiplate structure hypervelocity impact simulation

Publication date: Available online 26 March 2025

Source: Advances in Space Research

Author(s): Xu Cao, Jianqiu Zhou, Huadong Xu, Di Song, Changqing Miao

Debiasing of Two-Line Element Sets for Batch Least Squares Pseudo-Orbit Determination in MEO and GEO

Publication date: Available online 26 March 2025

Source: Advances in Space Research

Author(s): Max I. Hallgarten La Casta, Davide Amato

Modelling Aerodynamic Drag of a Very Low Earth Orbit 1U CubeSat Utilising a Boltzmann-BGK Approach

Publication date: Available online 26 March 2025

Source: Advances in Space Research

Author(s): Joseff Parke Sturrock, Ben Evans, Zoran Jelic

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