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The Tibetan Plateau, together with the Hindu Kush–Karakorum–Himalaya region, has more snow and ice than any other region on Earth apart from the polar regions. As a result, this high-altitude region is particularly sensitive to climate change, making it especially important in analyzing its impacts. In recent years, researchers from the DFG Research Training Group TransTiP have been investigating changes in the region's geo-ecosystems.

High-resolution sediment analyses from the Arabian Sea reveal, for the first time, that summer and winter monsoons respond differently to global climate change. The study enhances understanding of past precipitation patterns and could help refine climate models for regions influenced by monsoons.

Research by atmospheric scientists at UC San Diego's Scripps Institution of Oceanography and colleagues pinpointed an individual coal-fired power plant in Houston as the main source of particles most likely to encourage the formation of clouds around the metropolitan area.

CSIRO hydrologist Dr. Jai Vaze has lost count of how many times over the past four years he has been asked if he can flood-proof the Northern Rivers region of New South Wales.

SummarySurface waves are sensitive to the shear wave velocity and low-velocity zone (LVZ). Here, we analyze the subsurface anomalies in the upper mantle beneath the Central Indian Ocean Basin (CIOB) utilising the ocean bottom seismometer (OBS) data. The Rayleigh wave dispersion curve analysis between earthquake clusters and OBS stations shows a period range between 12 and 300 s for the fundamental modes. A significant decrease in group velocity is observed at an intermediate period (60-180 s). The estimated depth of the lithospheric base is ∼81 km, ∼68 km, ∼67 km, and ∼82 km for P1, P2, P3, and P4 profiles respectively. A significant reduction in Vsv velocity is observed beneath the lithospheric base (i.e. ∼22-24 km thick Lithosphere-Asthenosphere boundary). Our results show an anomalous LVZ between ∼80 km and ∼170 km depth interval beneath the CIOB. A ∼18–20 per cent reduction in Vsv velocity within the LVZ suggests the presence of ∼1.9–2.0 per cent melt fraction in the shallow asthenosphere along P2 (∼3.7 km/s) and P3 (∼3.73 km/s) profiles. An excess temperature of ∼230°C is inferred across the P1-P4 profiles in the vicinity of LVZ beneath the CIOB. Henceforth, we propose a mechanism in which the presence of an unextracted melt fraction, in conjunction with the northward movement of the Indian plate and supplemented by plume-lithosphere interaction, can account for the formation and persistence of anomalous LVZ in the upper mantle. An additional ∼1 per cent melt within the LVZ along the P2 and P3 profiles, relative to the P1 and P4 profiles, favours the possibility of the west-to-east channelized asthenospheric flow beneath the CIOB region.

Oceanic transform faults are strike-slip boundaries—faults that move horizontally rather than up and down and connect offset mid-ocean ridge segments. They have long been regarded as simple "conservative" plate boundaries that slide past each other without creating or destroying Earth's crust. However, mounting evidence suggests that these faults are influenced by magmatism and hydrothermal circulation, exhibiting complex three-dimensional structures.

An international expedition including University of Sydney researchers has pieced together the clearest picture yet of how the Great Barrier Reef responded to dramatic environmental change over the past 30,000 years. Multiple studies since the expedition more than 10 years ago have traced the reef's retreat, regrowth and repeated collapse from the last ice age to the dawn of the modern reef.

Venezuela has a well-documented vulnerability to earthquakes. The country sits on the boundary between the Caribbean and South American tectonic plates, resulting in routine tremors and causing historical earthquake disasters. But the experience of a "doublet," a pair of 7.2- and 7.5-magnitude earthquakes 40 seconds apart, on June 24 was a rare misfortune.

The Antarctic ozone hole was discovered in 1985, when scientists observed a severe depletion in Earth's protective layer of stratospheric ozone. Industrial chemicals known as chlorofluorocarbons (CFCs), then widely used as refrigerants, propellants, foam-blowing agents and solvents, were at the root of the ozone depletion. After a concerted global effort to phase out the use of CFCs, ozone today is recovering, especially in the Antarctic.

New research led by the University of New England's Dr. Timothy Chapman has uncovered the trigger behind slow earthquakes, providing valuable answers for those living in disaster-prone areas. The research has been published in Geology.

In the aftermath of back-to-back earthquakes in northern Venezuela, which by Friday had killed more than 500 people and left thousands injured, experts in resilience planning have emphasized the increasing importance of disaster preparedness in earthquake-prone California.

Author(s): J. H. Kunimune, D. T. Casey, B. Kustowski, M. Jones, L. Divol, T. M. Johnson, S. G. Dannhoff, A. DeVault, and J. A. Frenje

Three-dimensional (3D) asymmetries and their associated residual kinetic energy (RKE) are a major performance-degradation mechanism in inertial-confinement fusion (ICF) implosions at the National Ignition Facility (NIF). These asymmetries can be diagnosed with the three neutron imaging systems field…

[Phys. Rev. E 113, 065213] Published Mon Jun 29, 2026

Human-driven climate change significantly intensified the retreat of one of the most important glaciers in Antarctica during the 20th century. The Pine Island Glacier, which drains a large part of the West Antarctic Ice Sheet into the Amundsen Sea, is one of the biggest contributors to global sea level rise.

Abstract

To meet the high-precision and high-integrity positioning demands of safety–critical applications, monitoring the quality of precise satellite products in global navigation satellite system (GNSS) precise point positioning (PPP) is crucial. This work employs ionosphere-free (IF) PPP with ambiguity resolution (PPP-AR) phase residuals to construct test statistics for monitoring the quality of precise satellite corrections. By utilizing precise satellite orbit and clock products from CODE, WUM, and GRG, the PPP-AR phase residuals were first analyzed with sample moments, Allan variance and power spectral density (PSD). The key findings are as follows: (1) The skewness and kurtosis results indicate that ambiguity-fixed phase residuals deviate from an ideal zero-mean Gaussian distribution and exhibit a super-Gaussian distribution. (2) Allan variance and PSD analysis reveal that flicker noise dominates the phase residuals. (3) The noise amplitudes are similar for all satellites, but certain differences are observed among different GNSS systems and satellite types. (4) The noise level of phase residuals is influenced by the receiver types, antenna types, and precise products from different analysis centers. Leveraging the error characteristics, the two-step Gaussian overbounding (OB) method was employed to estimate the corresponding OB parameters of the phase residuals. The overbounding results demonstrate that, under similar conditions, phase residuals can be bounded by the calculated bound within the acceptable integrity risk after removing the detected outliers. Anomaly monitoring experiments further show that phase residuals can effectively capture anomalies in precise satellite corrections, with the set threshold successfully detecting such anomalies.

The measurement of virtual height of the sporadic E layer (h'Es) is very sensitive to the type of ionosonde used and the calibration processes. The ionosondes used by the national institute of communication an...

Abstract

Solar photospheric abundances and CI-chondrite compositions are reviewed and updated to obtain representative solar system abundances of the elements and their isotopes. The new photospheric abundances obtained here lead to higher solar metallicity. Full 3D NLTE photospheric analyses are only available for 11 elements. A quality index for analyses is introduced. For several elements, uncertainties remain large. Protosolar mass fractions are H (X = 0.7060), He (Y = 0.2753), and for metals Li to U (Z = 0.0187). The protosolar (C+N)/H agrees within 13% with the ratio for the solar core from the Borexino experiment. Elemental abundances in CI-chondrites were screened by analytical methods, sample sizes, and evaluated using concentration frequency distributions. Aqueously mobile elements (e.g., alkalis, alkaline earths, etc.) often deviate from normal distributions indicating mobilization and/or sequestration into carbonates, phosphates, and sulfates. Revised CI-chondrite abundances of non-volatile elements are similar to earlier estimates. The moderately volatile elements F and Sb are higher than before, as are C, Br and I, whereas the CI-abundances of Hg and N are now significantly lower. The solar system nuclide distribution curves of s-process elements agree within 4% with s-process predictions of Galactic chemical evolution models. P-process nuclide distributions are assessed. No obvious correlation of CI-chondritic to solar elemental abundance ratios with condensation temperatures is observed, nor is there one for ratios of CI-chondrites/solar wind abundances.

The January 2022 Tonga volcanic eruption generated atmospheric pressure waves that propagated over the ocean’s surface and triggered a meteotsunami. This meteotsunami caused significant amplitudes exceeding 10...

Abstract

Accurately modeling and prediction the nonlinear motion of GNSS (Global Navigation Satellite System) coordinate time series holds significant theoretical and practical value for the study of geodynamics. A novel integrated network, named Ensemble Learning method based on Signal Source Driver (ELSSD), is proposed, which leverages the strengths of Long Short-Term Memory (LSTM) and Deep Self-Attention Neural Network (DSANN), while integrating GNSS loading data as an additional data source. Additionally, a multi-track synchronous sliding window data processing strategy is designed to address the challenge of multi-source data fusion input. The effectiveness of this algorithm is validated using GNSS coordinate time series from 186 global stations over a period of 10 years. Experimental results initially illustrate that, when accounting for displacement caused by environmental loading effects, there is a marked improvement in the modeling and prediction accuracy compared with GNSS input-only. Furthermore, the application of three ensemble network strategies-Bagging, Boosting, and Stacking-have further been demonstrated to enhance modeling and prediction accuracy. Compared with LSTM and DSANN networks, the proposed ELSSD algorithm achieves an average RMSE (Root Mean Square Error) of 3.6 mm for both modeling and prediction, with modeling accuracy improvements of 4.8% and 6.2%, while prediction accuracy improvements of 5.4% and 5.9%, respectively. With respect to the traditional Least Square method, there is an improvement of 22.1% and 27.9% in modeling and prediction accuracy, respectively. Regarding noise characteristics, there is a significant reduction in colored noise amplitude, with decreases of 36.7% and 36.0% observed in modeling and prediction, respectively. Simultaneously, the velocity uncertainty experiences an average reduction of 27.1% and 27.5%. The average velocity differences are measured at 0.06 mm/year and 0.24 mm/year, respectively. Hence, our findings suggest that the ELSSD algorithm emerges as an effective methodology for handling multi-source data input in GNSS coordinate time series, presenting promising practical applications in the field.

The Mw 7.5 Noto Peninsula earthquake, which occurred on January 1, 2024, was considerably hazardous to the peninsula and surrounding regions owing to a strong motion, large-scale crustal deformation, and subse...

Nature Geoscience, Published online: 21 February 2025; doi:10.1038/s41561-025-01653-z

Quartz-rich clasts in Martian meteorite NWA 7533 indicate the presence of granitic rocks on early Mars that formed via hydrothermal activity and impact melting, according to petrologic and in situ geochemical analyses.