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Tracking and predicting sea level rise involves more than measuring the height of our oceans: Land along coastlines also inches up and down in elevation. Using California as a case study, a NASA-led team has shown how seemingly modest vertical land motion could significantly impact local sea levels in coming decades.

Scientists in Scotland have developed a new method to understand the heat and intensity of fires that burned out millions of years ago, which could unlock our understanding of wildfires during past and present periods of climate change.

Recent wildfires are larger and more intense than they've ever been in the historical record. If you've been watching the news at any point in the last decade, that's no surprise.

The surface of the Earth's inner core may be changing, as shown by a new study by USC scientists that detected structural changes near the planet's center, published in Nature Geoscience.

In 2018, the side of the Anak Krakatau volcano collapsed in a powerful eruption and produced a tsunami that killed hundreds and injured thousands on nearby Java and Sumatra in Indonesia. A new analysis of satellite data showed the mountainside was slipping for years and accelerated before the eruption—information that could have potentially offered a warning of the collapse.

Throughout the world, extreme weather is driving a growing death toll, exacting billions in damage, threatening food and water security and escalating forced migration. Yet some of the most sophisticated climate models—computer simulations of the Earth's vast, complex climate system, based upon the laws of physics—are missing crucial signals.

Beryllium-10, a rare radioactive isotope produced by cosmic rays in the atmosphere, provides valuable insights into the Earth's geological history. A research team from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), in collaboration with the TUD Dresden University of Technology and the Australian National University (ANU), has discovered an unexpected accumulation of this isotope in samples taken from the Pacific seabed.

Nature Geoscience, Published online: 10 February 2025; doi:10.1038/s41561-025-01647-x

The rigid-body motion of Earth’s wandering inner core has now been reliably tracked over the past 20 years. With this knowledge, we can compare seismic recordings obtained when the inner core returns to the same position after moving for several years. More is changing than just the inner core position; the soft outermost inner core probably deforms.

Nature Geoscience, Published online: 10 February 2025; doi:10.1038/s41561-025-01642-2

Earth’s inner core has both changed its relative rotation rate and deformed in the past few decades, according to an analysis of seismic waves recorded when the inner core occupied the same relative location owing to its changing rotation rate.

SummaryGeodetic velocity models, derived from Global Navigation Satellite System (GNSS) velocity solutions, interpolate between sparse GNSS measurements to provide a more comprehensive view of horizontal and vertical intraplate deformation. These models contribute to improved assessment of seismic and volcanic hazards, assist in validating geodynamic models, and enable the integration of diverse datasets for comprehensive Earth science studies. Most interpolation techniques are not adequate to model the velocity distribution, especially for the horizontal velocities where the correlation between the components has to be included. Here, we apply a recent extension of the least-squares collocation interpolation technique to the velocity field solution of the EUREF Permanent GNSS Network Densification (EPND) project (EPND_D2150). The effect of known plate boundaries is accounted for during the interpolation to avoid smoothing across European micro-plates, thereby preserving the high velocity gradients at plate boundaries. The velocity model EuVeM2022 covers Europe and Anatolia, and has a resolution of 0.1○. The model can be applied, amongst other things, to correct models used for ground motion services, support tectonic studies, or identify local deformation along coasts for use in sea-level research.

SummaryThe leaky-mode dispersion extracted from seismograms and noise cross-correlation functions has gained lots of attention in recent years. It has been reported that leaky modes can provide constraints for subsurface structures, especially for P-wave velocities, which may compensate for the limits of traditional surface wave methods. For stable and reliable dispersion-curve inversion, the quantitative analysis of leaky-mode sensitivity is of great importance, which, however, has rarely been studied systematically. Limited by the forward modeling methods, the previous methods for calculating leaky-mode sensitivity are usually hindered by issues of mode skipping, low efficiency, etc. To this end, we propose an effective method that can calculate the leaky-mode sensitivity for various types of models based on the previously proposed forward modeling method named the semi-analytical spectral element method (SASEM). Using the intermediate results of SASEM, we derive analytical expressions for the sensitivity kernels with only matrix operations, which endows the sensitivity calculation procedure with high accuracy and reliability identical to the SASEM. In addition, we suggest a novel modal classification scheme to distinguish different kinds of leaky modes based on the sensitivity features. This scheme facilitates the stable identification of the most attractive guided-P modes from numerous normal and leaky modes, which removes obstacles in the dispersion-curve inversion using guided-P modes to constrain P-wave velocities. Several numerical tests are performed to demonstrate the high accuracy of the sensitivity calculation method and the effectiveness of the modal classification method. To assess the roles of leaky modes in the retrieval of underground structures, we perform comprehensive sensitivity analyses of leaky modes using both crust-scale and near-surface models. Besides the general conclusion that the joint inversion using normal and leaky modes can effectively retrieve P- and S-wave velocities, the feasibility of constraining models with the apparent Σ modes and the split guided-P mode dispersion curves has been demonstrated.

Abstract

The seismo-electromagnetic studies have been in progress since 1998 at Agra station. In the present paper, ionospheric GPS-TEC, ground-based ULF/VLF measurements were investigated in light of four strong earthquakes (M ≥ 6.8) that occurred around the Indian subcontinent in different periods. These three datasets are processed by using advanced signal-processing techniques in time and frequency domains. To analyze these datasets, a period of 16 days (including the day of the earthquake) was considered. For each day, only one minute of data was taken into account, with the time of the earthquake being the midpoint of that minute. The precursors are obtained in all the datasets considered before the occurrence of earthquakes. In TEC, ULF, and VLF data, significant changes are observed 2 to 15, 2 to 7, and 5 to 13 days before earthquakes, respectively. Significant results are obtained in time and frequency domains and the variations of solar and magnetic storm activities have also been examined thoroughly to check the validity of these variations. Further, these variations are interpreted in terms of lithosphere-atmosphere-ionosphere coupling mechanisms available in the literature.

Abstract

This study investigates Pc5 pulsations during the St. Patrick’s Day geomagnetic storm of March 17, 2015, using ground-based magnetic data from the SER station in Chile (29.827° S, 71.261° W), satellite observations, and geomagnetic indices. Pc5 pulsations, with frequencies of 1.67–6.67 mHz, are influenced by various factors, including the Kelvin–Helmholtz instability, field line resonance effects, and solar wind dynamics. During this storm ignificant variations in solar wind parameters were observed, with positive correlations between Pc5 pulsations and parameters like temperature, density, speed, and pressure, especially during the main and recovery phases Pc5 pulsations exhibited large amplitudes during the storm, potentially driven by magnetospheric MHD waveguide/cavity mode and induced by the substantial compression of the geomagnetic field from the solar wind. Our results show the appearance of Pc5 pulsations at low latitudes and strong correlations between solar wind parameters and Pc5 signals during all storm phases, with maximum correlation coefficients of 0.98.

Abstract

The occurrence of geomagnetic storms and the variation in the geomagnetic storm indices during the ascending phase of solar cycle 24 has been examined. The parameters considered for this study includes; IMF Bz (nT), solar wind speed ( \({{{v}}_{x}}\) , in km/s), Dst index (nT), Aurora Electroject (AE, AU and AL indices in nT), and sunspot number. The datasets span from 2010 to 2012. Results of the study reveals that; the frequency of occurrence of geomagnetic storms increases with the increase in solar activity. Six (6) geomagnetic storms were recorded in 2010 (with sunspot number, Rz = 16.5), 13 storms in 2012 (with sunspot number Rz = 55.7), and 17 storms occurred in 2012 (with sunspot number, Rz = 57.5) giving a total of 36 geomagnetic storm events for the entire period. The performed study demonstrates that an increase in the speed and density of the solar wind coincided with the decrease in the Dst index in 58% cases (in 21 out of 36 geomagnetic storms). However, in some cases, there was a sharp simultaneous increase in both the speed and density of the solar wind that fell on the recovery phase of the storm. This also in most cases coincided with the sharp north-south fluctuations in the IMF Bz. These variations cannot be unconnected with the nature of the drivers of such geomagnetic storms. It is evident that the behavior of the solar wind speed during geomagnetic storm events can provide meaningful insight on the underlying mechanisms and processes that drive the geomagnetic storm.

Nature Geoscience, Published online: 10 February 2025; doi:10.1038/s41561-024-01629-5

Diverse lithospheric rocks show nanoporosity that changes the geochemistry of fluids and rock reactivity during fluid–rock interactions, according to a study including electron microscopy, molecular dynamics and thermodynamic modelling.

Nature Geoscience, Published online: 10 February 2025; doi:10.1038/s41561-025-01649-9

Ocean pH probably rose rapidly in the Hadean and early Archaean due to elevated rates of seafloor and continental weathering, according to a model integrating global carbon cycling and ocean geochemistry with continental growth and mantle thermal evolution.

Abstract

Magnetic reconnection is a ubiquitous plasma process that transforms magnetic energy into particle energy during eruptive events throughout the universe. Reconnection not only converts energy during solar flares and geomagnetic substorms that drive space weather near Earth, but it may also play critical roles in the high energy emissions from the magnetospheres of neutron stars and black holes. In this review article, we focus on collisionless plasmas that are most relevant to reconnection in many space and astrophysical plasmas. Guided by first-principles kinetic simulations and spaceborne in-situ observations, we highlight the most recent progress in understanding this fundamental plasma process. We start by discussing the non-ideal electric field in the generalized Ohm’s law that breaks the frozen-in flux condition in ideal magnetohydrodynamics and allows magnetic reconnection to occur. We point out that this same reconnection electric field also plays an important role in sustaining the current and pressure in the current sheet and then discuss the determination of its magnitude (i.e., the reconnection rate), based on force balance and energy conservation. This approach to determining the reconnection rate is applied to kinetic current sheets with a wide variety of magnetic geometries, parameters, and background conditions. We also briefly review the key diagnostics and modeling of energy conversion around the reconnection diffusion region, seeking insights from recently developed theories. Finally, future prospects and open questions are discussed.

Abstract

A 6-year cycle has long been recognized to influence the Earth’s rotation, the internal magnetic field and motions in the fluid Earth’s core. Recent observations have revealed that a 6-year cycle also affects the angular momentum of the atmosphere and several climatic parameters, including global mean sea level rise, precipitation, land hydrology, Arctic surface temperature, ocean heat content and natural climate modes. In this review, we first present observational evidences supporting the existence of a 6-year cycle in the Earth system, from its deep interior to the climate system. We then explore potential links between the Earth’s core, mantle and atmosphere that might explain the observations, and investigate various mechanisms that could drive the observed 6-year oscillation throughout the whole Earth system.

Abstract

As a critical parameter in meteorological monitoring, precipitable water vapor (PWV) is widely used in short-term extreme weather forecasting and long-term climate change research. However, as PWV exhibits significant vertical attenuation, especially within 2 km, achieving accurate vertical interpolation is essential for comparisons and fusion across different measurement techniques, such as sampling water vapor at different heights. PWV vertical adjustment relies only on the empirical or time-varying lapse rate models (e.g., GPWV-H). The non-uniform vertical distribution of PWV and the uncertain variation trend in the low-latitude region still limit the accuracy. To address these issues, we propose the Spatially enhanced Vertical Adjustment Model for PWV (SPWV-H), taking into account the non-uniform distribution in the vertical direction based on the fifth-generation European Centre for Medium-Range Weather Forecasts Atmospheric Reanalysis (ERA5) products. The assessment, validated against the ERA5 benchmark, highlights the SPWV-H model’s superior performance with an RMSE of 1 mm and a bias of 0.03 mm, especially pronounced in the low-latitude region. Compared to global radiosonde datasets, the SPWV-H model achieves notable reductions in RMSE of 12%, 11%, and 18% when evaluated against the EPWV-H, GPWV-H, and GPT3-1 models, respectively. In spatial interpolation, the SPWV-H model achieves an RMSE of 1.22 mm, indicating an improvement of 10%, 9%, and 14% compared to the EPWV-H, GPWV-H, and GPT3-1 models, respectively. Therefore, the SPWV-H model can provide a reliable service for multi-source PWV fusion and real-time PWV monitoring by GNSS.

Abstract

In February 2023, the International Laser Ranging Service started the tracking of additional medium Earth orbit satellites from the global BeiDou navigation satellite system (BDS) constellation, increasing the total number of tracked BDS satellites to 27. As an optical space geodesy technique, the Satellite Laser Ranging (SLR) provides another important measurement for BDS other than the microwave (L-band) one. Based on three years of data from June 2021 to May 2024, the potential benefits of introducing SLR data into BDS processing and analysis are investigated from three key aspects: orbit validation, precise orbit determination, and geodetic parameters estimation. The independent SLR validations of BDS precise orbit products from four analysis centers show that using the a priori box-wing model for solar radiation pressure (SRP) modeling can achieve superior performance than purely empirical models. The results also indicate the existence of SRP modeling deficiencies for some satellites such as C45 and C46 with Search and Rescue payloads. Given a sparse ground network with 5 stations, the introduction of SLR significantly stabilizes the SRP parameter estimates and improves the orbit accuracy by 44.4%. In terms of geodetic parameter estimation, the scatter of the Z-component geocenter motion can be effectively reduced with the inclusion of SLR data, presenting 10.9–15.3% smaller root mean square (RMS) values during February 2023 and May 2024, depending on the SRP models. In addition, the annual amplitudes of the Z-component geocenter motion are reduced by 7.2–48.2%. The improvement is more pronounced with a limited number of microwave stations, due to the greater strength of SLR observations in geocenter motion estimation. On the other hand, since the SLR observations are unhomogeneously distributed in both space and time, the incorporation of SLR does not evidently enhance the accuracy of Earth rotation parameters, and may even to some extent contaminate the results when the number of microwave stations is limited.