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Rivers, streams, lakes, and reservoirs aren't just scenic parts of our landscape—they're also vital engines for life on Earth. These inland waters "breathe" oxygen, just like we do. But a new study led by Utrecht University researchers shows that we've been suffocating them during the last century, an era also known as the Anthropocene. The research, published today in Science Advances, reveals that the way oxygen is produced and used in inland waters has dramatically changed since 1900. The culprit? Human activities.

The world's most powerful ocean current could slow by 2050

Phys.org: Earth science - Fri, 04/04/2025 - 17:19

The ocean is a vital part of our planet's climate system. Through its global circulation patterns, the ocean draws vast quantities of our planet's heat and carbon dioxide out of the atmosphere.

Ancient lakes and rivers unearthed in Arabia's vast desert

Phys.org: Earth science - Fri, 04/04/2025 - 16:40

The desert that we see today in Arabia was once a region that repeatedly underwent "green" periods in the past, as a result of periods of high rainfall, resulting in the formation of lakes and rivers about 9,000 years ago.

Scientists discover deep-sea microplastic hotspots driven by fast-moving underwater avalanches

Phys.org: Earth science - Fri, 04/04/2025 - 15:40

Fast-moving underwater avalanches, known as turbidity currents, are responsible for transporting vast quantities of microplastics into the deep sea, according to new research published today.

Underwater robotic gliders provide new insights into the impact of a melting megaberg

Phys.org: Earth science - Fri, 04/04/2025 - 15:07

For the first time, scientists have collected measurements close to a giant iceberg, giving an unprecedented window into the impact of meltwater on the surrounding Southern Ocean and ecosystem. The paper is published today (4 April 2025) in the journal Nature Geoscience.

Soil conditions significantly increase rainfall in world's megastorm hotspots, study shows

Phys.org: Earth science - Fri, 04/04/2025 - 13:18

Storm forecasting is traditionally based on studying atmospheric conditions, but research that also looks at land surface conditions is set to transform early warning systems in tropical regions. This will enable communities to better adapt to the destructive impacts of climate change.

Southern Ocean warming may affect tropical drought and rainfall more than Arctic warming

Phys.org: Earth science - Fri, 04/04/2025 - 12:47

Southern Ocean warming may have a greater impact than Arctic warming in some regions, particularly affecting tropical rainfall patterns, according to a study published in Nature Communications. These effects could exacerbate weather and climate extremes in vulnerable regions.

Quadrilateral particle arrangement within shocks in a two-dimensional dusty plasma

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

Author(s): Anton Kananovich and J. Goree

The microscopic structure within a two-dimensional shock was studied using data from a dusty plasma experiment. A single layer of charged microparticles, levitated in a glow-discharge plasma, was perturbed by an electrically floating wire that was moved at a steady supersonic speed to excite a compr…

[Phys. Rev. E 111, 045201] Published Fri Apr 04, 2025

Uncertainty quantification of FWI solutions using sequential local ensemble transform Kalman filter for full waveform data

Geophysical Journal International - Fri, 04/04/2025 - 00:00

SummaryFull waveform inversion (FWI) has enjoyed increased attention the past decade, becoming the state of the art for estimating parameters influencing wave propagation in a medium. However, only a few recent emerging efforts have attempted to tackle the challenge of uncertainty quantification in FWI. In this study, we suggest joining FWI with the Bayesian approach, where we provide a post-processing step with an advantageous starting point defined by the global minimum stemming from a deterministic FWI algorithm. Then, using the local ensemble transform Kalman filter (LETKF), we obtain the uncertainty as a follow-up step to the FWI procedure. Within a probabilistic Bayesian inversion framework, the LETKF uses local seismic data to update sets of variables in the subsurface domain. Seismic data for each shot and receiver in the time-domain is in this way matched with subsurface layers, and assimilated in a sequential manner. The methodology is showcased on a realistic model of the Gullfaks field in the North Sea, where we study effects of various seismic acquisition design set-ups, algorithm and model parameter settings. We investigate how these acquisition designs and parameters influence the uncertainty reduction and bias of the inversion results. We highlight the importance of studying statistical performance metrics to ensure a balance between bias and underestimation of uncertainty.

Global 0.05○ Water Storage Simulations with the OS LISFLOOD Hydrological Model for Geodetic Applications

Geophysical Journal International - Fri, 04/04/2025 - 00:00

SummaryModel-based information about the global water cycle, in particular the redistribution of terrestrial water masses, is highly relevant for the understanding of Earth system dynamics. In many geodetic applications, hydrological model results play an important role by augmenting observations with a higher spatio-temporal resolution and gapless coverage. Here we demonstrate the feasibility of the high-resolution, open-source hydrological model OS LISFLOOD to simulate terrestrial water storage (TWS) variations with a spatial sampling of up to about 5 km (0.05○). Validation against data from satellite gravimetry reveals that the choice of the maximum soil depth has a significant impact on long-term trends in TWS, mainly in the deepest soil layer. We find that refining the soil depth definition effectively reduces spurious TWS trends, while preserving accuracy in modeled river discharge. Using the modified model set-up, we show that in many regions TWS from OS LISFLOOD fits better to observations than TWS from the Land Surface Discharge Model (LSDM) routinely operated at the GFZ and used in geodetic applications worldwide. The advantage of the high spatial resolution of the OS LISFLOOD implementation is shown by comparing vertical surface displacements to GNSS observations in a global network of stations. The data set presented here is the first application of OS LISFLOOD to generate quasi-global (regions south of 60○S excluded) daily 0.05○ TWS fields for a 23-year period (2000–2022).

Auroral-oval activity during the intense magnetic storm of May 2024 – Overcoming the underestimation of the <em>AE</em> index

Recent articles in Advances in Space Research - Thu, 04/03/2025 - 19:10

Publication date: Available online 25 March 2025

Source: Advances in Space Research

Author(s): Fridrich Valach, Miloš Revallo, Eduard Koči