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Earth's water cycle: Study reveals how climate change may alter hydrology of grassland ecosystems

Phys.org: Earth science - Thu, 01/16/2025 - 19:00
Research co-led by the University of Maryland reveals that drought and increased temperatures in a CO2-rich climate can dramatically alter how grasslands use and move water.

40-year study suggests extreme droughts will become more frequent and severe

Phys.org: Earth science - Thu, 01/16/2025 - 19:00
Increasingly common since 1980, persistent multi-year droughts will continue to advance with the warming climate, warns a study from the Swiss Federal Institute for Forest, Snow, and Landscape Research (WSL), with Professor Francesca Pellicciotti from the Institute of Science and Technology Austria (ISTA) participating.

New evidence suggests sulfur's role in dinosaur extinction was overstated

Phys.org: Earth science - Thu, 01/16/2025 - 17:21
Approximately 66 million years ago, the Chicxulub asteroid, estimated to be 10–15 kilometers in diameter, struck the Yucatán Peninsula (in current-day Mexico), creating a 200-kilometer-wide impact crater. This impact triggered a chain reaction of destructive events, including a rapid climate change that eventually led to the extinction of the non-avian dinosaurs and, in total, about 75% of species on Earth.

Biochar shown to reduce risks of DDT-contaminated soil

Phys.org: Earth science - Thu, 01/16/2025 - 15:35
Dichlorodiphenyltrichloroethane (DDT) soil pollution is still a major problem in many parts of the world. Researchers at Chalmers University of Technology, Sweden, have developed a new method to manage ecological risks from the toxin by binding it with biochar. When they mixed biochar into contaminated soil at a former tree nursery, DDT uptake by earthworms in the soil was halved. This method may enable the growing of certain crops on land that is currently considered unusable due to environmental risks.

Permafrost thaw threatens up to 3 million people in the Arctic

Phys.org: Earth science - Thu, 01/16/2025 - 15:32
Permafrost thaw poses multiple risks to local Arctic communities, their livelihoods, infrastructure and environment. A transdisciplinary study led by Umeå University and others has identified key risks across four Arctic regions. This allows communities to adapt and make informed decisions.

Devastating volcanic eruption did not cause the sudden-onset cold period 13,000 years ago, climate archives reveal

Phys.org: Earth science - Thu, 01/16/2025 - 15:30
The synchronization of data from two natural climate archives—a speleothem from the Herbstlabyrinth Cave in Hesse (Germany) and ice cores from Greenland—offers new insights into the chronology of abrupt climate changes in Central Europe.

Protective actions need regulatory support to fully defend homeowners and coastal communities, study finds

Phys.org: Earth science - Thu, 01/16/2025 - 14:41
As climate change drives increasingly severe hurricanes, U.S. coastal communities are bearing the brunt of mounting losses. With regulations failing to curb the damage, homeowners have become the front line of defense—but their efforts often fall short, a recent study reveals.

Arctic hotspots study reveals areas of climate stress in Northern Alaska and Siberia

Phys.org: Earth science - Thu, 01/16/2025 - 14:04
Ecological warning lights have blinked on across the Arctic over the last 40 years, according to new research, and many of the fastest-changing areas are clustered in Siberia, the Canadian Northwest Territories, and Alaska.

Rockfall frequency from French mountains has doubled since Little Ice Age

Phys.org: Earth science - Thu, 01/16/2025 - 13:00
The Little Ice Age was a period of significant cooling from the early 14th to mid-19th centuries, which saw mean temperatures across the northern hemisphere drop by up to 2°C and the advancement of glaciers.

First-principles molecular-dynamics equation of state of liquid to dense plasma iron

Physical Review E (Plasma physics) - Thu, 01/16/2025 - 10:00

Author(s): Augustin Blanchet, François Soubiran, Marc Torrent, and Jean Clérouin

We computed the equation of state of iron using extended first-principles molecular dynamics simulations, ranging from 7.874g/cm3 and 5500 K up to 47.2g/cm3 and 109K. We compared the principal Hugoniot curve with semiempirical models, average atom-based model predictions, and shock experiment result…


[Phys. Rev. E 111, 015206] Published Thu Jan 16, 2025

Author Correction: Recent uplift of Chomolungma enhanced by river drainage piracy

Nature Geoscience - Thu, 01/16/2025 - 00:00

Nature Geoscience, Published online: 16 January 2025; doi:10.1038/s41561-025-01643-1

Author Correction: Recent uplift of Chomolungma enhanced by river drainage piracy

Direction finding in an active source experiment in Fürstenfeldbruck, Germany using 6 DoF measurements

Geophysical Journal International - Thu, 01/16/2025 - 00:00
SummaryThe seismic wavefield is fully described by translation, rotation and strain. Until recently, the seismological community has not been able to measure rotation directly with portable sensors with satisfactory resolution. Portable blueSeis-3A (Exail) sensors allow measuring 3 components of rotational motions. Co-located with conventional seismometers, one can locally observe six degrees of freedom (6 DoF) of ground motion. To test the performance of the rotational sensors, an active source experiment was carried out in Fürstenfeldbruck, Germany, in November 2019. Five explosions with different yields and distances from our sensors, were fired. In a first stage, eight rotational sensors were deployed inside a bunker next to a seismometer. In a second stage, the rotational sensors were installed in two clusters of 4 sensors each. We compare the back azimuths derived using two different methods: (i) a method using horizontal rotational components and (ii) a standard polarization analysis using only 3C translational data. Back azimuths calculated using rotational data for 5 explosions have an average 10.2○ deviation from the theoretical back azimuths. Estimates using 3C translational data for the first stage of the experiment have a 1.8○ deviation from the theoretical back azimuth. For the second stage we found a 29.4○ deviation using the seismometer from stage 1. We conclude that within our distance range from 50 m to 1070 m, all rotational sensors provide reliably back azimuths of explosive sources when using only horizontal rotational components. For future applications of rotational sensors in other environments this is promising as back azimuths can be derived reliably.

Stabilized mascon solutions through combinations of GRACE and SLR normal equations

Geophysical Journal International - Thu, 01/16/2025 - 00:00
SummaryA new global mascon solution using GRACE and GRACE Follow-On data is co-estimated with Satellite Laser Ranging (SLR) measurements to seven major geodetic satellites. This combined solution is compared with an otherwise similar GRACE-only solution to determine improvements in the estimate. We find similar performance between both solutions in the recovered mass change, but significant improvements in the associated errors in the combination solution. Errors in recovered basin mass change are 10-20% better for the combination solution across all basin sizes, with the greatest improvements in high latitude ice sheets. These results lead to our recommendation that all GRACE Level 3 mascon and spherical harmonic user-oriented gridded solutions should include SLR information during the solution inversion. As an ancillary contribution, we also provide validation of the choice of truncated spherical harmonics used in determining GRACE Technical Note 14, the current recommended mechanism for including SLR information with GRACE solutions in post-processing.

Tidal Deformation and Dissipation Processes in Icy Worlds

Space Science Reviews - Thu, 01/16/2025 - 00:00
Abstract

Tidal interactions play a key role in the dynamics and evolution of icy worlds. The intense tectonic activity of Europa and the eruption activity on Enceladus are clear examples of the manifestation of tidal deformation and associated dissipation. While tidal heating has long been recognized as a major driver in the activity of these icy worlds, the mechanism controlling how tidal forces deform the different internal layers and produce heat by tidal friction still remains poorly constrained. As tidal forcing varies with orbital characteristics (distance to the central planet, eccentricity, obliquity), the contribution of tidal heating to the internal heat budget can strongly change over geological timescales. In some circumstances, the tidally-produced heat can result in internal melting and surface activity taking various forms. Even in the absence of significant heat production, tidal deformation can be used to probe the interior structure, the tidal response of icy moons being strongly sensitive to their hydrosphere structure. In the present paper, we review the methods to compute tidal deformation and dissipation in the different layers composing icy worlds. After summarizing the main principle of tidal deformation and the different rheological models used to model visco-elastic tidal response, we describe the dissipation processes expected in rock-dominated cores, subsurface oceans and icy shells and highlight the potential effects of tidal heating in terms of thermal evolution and activity. We finally anticipate how data collected by future missions to Jupiter’s and Saturn’s moons could be used to constrain their tidal response and the consequences for past and present activities.

Clouds have a surprising effect on surface warming, climate researchers find

Phys.org: Earth science - Wed, 01/15/2025 - 19:26
McGill University researchers have discovered that changes in clouds are slightly mitigating global warming. While greenhouse gases continue to cause temperatures to rise, a reduction in low-cloud cover over land has brought about a modest reduction of the amount of heat being trapped close to ground level.

Large burial flux of modern organic carbon in the St. Lawrence estuarine system indicates a substantial atmospheric carbon sink

Earth and Planetary Science Letters - Wed, 01/15/2025 - 19:10

Publication date: 15 February 2025

Source: Earth and Planetary Science Letters, Volume 652

Author(s): Yunfeng Wang, Jason M.E. Ahad, Alfonso O. Mucci, Yves Gélinas, Peter M.J. Douglas

Evidence for the role of tropical plumes in driving mid-Holocene north-west Sahara rainfall

Earth and Planetary Science Letters - Wed, 01/15/2025 - 19:10

Publication date: 15 February 2025

Source: Earth and Planetary Science Letters, Volume 652

Author(s): Hamish O. Couper, Christopher C. Day, Julia J. Barrott, Samuel J. Hollowood, Stacy A. Carolin, Ben Lovett, Abdeljalil Bouzouggar, Nick Barton, Gideon M. Henderson

Mantle discontinuities and reflectors beneath the Arctic Ocean and Aleutian-Alaska subduction zone: Evidence for MORB crust at the top of the lower mantle

Earth and Planetary Science Letters - Wed, 01/15/2025 - 19:10

Publication date: 15 February 2025

Source: Earth and Planetary Science Letters, Volume 652

Author(s): Y. Yuan, J.K. Magali, X. Deng, D. Sun, C. Thomas

Vanadium isotope fractionation during early planetary evolution: Insights from achondrite analyses

Earth and Planetary Science Letters - Wed, 01/15/2025 - 19:10

Publication date: 15 February 2025

Source: Earth and Planetary Science Letters, Volume 652

Author(s): D.V. Bekaert, M. Auro, K. Righter, L.D. Peterson, A.W. Heard, D. Davis, E. Füri, Y. Marrocchi, A.J. Irving, K. Prissel, K. Burton, C. Fitoussi, S.G. Nielsen

Rheological and topographic implications of thermal insulation created by supercontinents

Earth and Planetary Science Letters - Wed, 01/15/2025 - 19:10

Publication date: 15 February 2025

Source: Earth and Planetary Science Letters, Volume 652

Author(s): João Pedro Macedo Silva, Victor Sacek, Carlos Eduardo Ganade, Gianreto Manatschal

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