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Publication date: 15 January 2025

Source: Advances in Space Research, Volume 75, Issue 2

Author(s): Taihe Huang, Jinxiu Zhang, Minghao Li, Yan Shen, Jianing Wu, Hui Wang

Publication date: 15 January 2025

Source: Advances in Space Research, Volume 75, Issue 2

Author(s): Ming Wang, Yongchen Yin, Chen Zhang, Hao Zhang

Publication date: 15 January 2025

Source: Advances in Space Research, Volume 75, Issue 2

Author(s): Wenjie Lv, Xiuqiang Jiang, Hechao Yang, Yuandong Ji, Guohao Sun, Suchuan Zhong

Publication date: 15 January 2025

Source: Advances in Space Research, Volume 75, Issue 2

Author(s): Jiasheng Li, Zhen Yang, Yazhong Luo

Publication date: 15 January 2025

Source: Advances in Space Research, Volume 75, Issue 2

Author(s): Wenchao Li, Jianlin Chen, Yang Yu, Chen Gao, Jianping Yuan

Publication date: 15 January 2025

Source: Advances in Space Research, Volume 75, Issue 2

Author(s): David Leiser, Christian Dürnhofer, Jérémie Vaubaillon, Peter Jenniskens, Stefan Löhle

Publication date: 15 January 2025

Source: Advances in Space Research, Volume 75, Issue 2

Author(s): Marco Felice Montaruli, Luca Facchini, Niccolò Faraco, Pierluigi Di Lizia, Mauro Massari, Germano Bianchi, Claudio Bortolotti, Andrea Maccaferri, Mauro Roma, Moreno Peroni, Luca Salotti, Elena Vellutini

Nature Geoscience, Published online: 12 February 2025; doi:10.1038/s41561-025-01646-y

Natural gradients across surface ocean regions show that changes in carbonate chemistry projected for ocean alkalinity enhancement could promote the proliferation of calcifying phytoplankton. This shift would increase an alkalinity sink, thus reducing the efficiency of ocean alkalinity enhancement as a CO2 removal method.

Nature Geoscience, Published online: 12 February 2025; doi:10.1038/s41561-025-01644-0

Intensive ocean alkalinity enhancement will cause a proliferation of calcifying organisms, which reduces its effectiveness as a carbon sequestration approach, according to an analysis of coccolithophore sensitivity to natural carbonate chemistry variability.

Abstract

The dynamics of the Earth’s outer radiation belt, filled by energetic electron fluxes, is largely controlled by electron resonant interactions with electromagnetic whistler-mode waves. The most coherent and intense waves resonantly interact with electrons nonlinearly, and the observable effects of such nonlinear interactions cannot be described within the frame of classical quasi-linear models. This paper provides an overview of the current stage of the theory of nonlinear resonant interactions and discusses different possible approaches for incorporating these nonlinear interactions into global radiation belt simulations. We focus on observational properties of whistler-mode waves and theoretical aspects of nonlinear resonant interactions between such waves and energetic electrons. We consider only sufficiently energetic particles, which can be treated as test particles and do not have a significant feedback to the waves. The review covers two main regimes of nonlinear resonant wave-particle interactions: the regime of long wave-packets, historically better studied, and the regime of short wave-packets, actively investigated more recently based on refined spacecraft observations.

Abstract

An International Space Science Institute (ISSI) workshop was convened to assess recent rapid advances in studies of magnetic reconnection made possible by the NASA Magnetospheric Multiscale (MMS) mission and to place them in context with concurrent advances in solar physics by the Parker Solar Probe, astrophysics, planetary science and laboratory plasma physics. The review papers resulting from this study focus primarily on results obtained by MMS, and these papers are complemented by reports of advances in magnetic reconnection physics in these other plasma environments. This paper introduces the topical collection “Magnetic Reconnection: Explosive Energy Conversion in Space Plasmas”, in particular introducing the new capabilities of the MMS mission used in majority of the articles in the collection and briefly summarizing the advances obtained from MMS.

Nature Geoscience, Published online: 11 February 2025; doi:10.1038/s41561-024-01633-9

Rhabdophane contains high concentrations of the rare earth elements, yet Tobias Bamforth argues that it remains underappreciated as a significant host of these critical metals.

Nature Geoscience, Published online: 11 February 2025; doi:10.1038/s41561-025-01651-1

Sustained monitoring is essential for assessing volcanic hazards. Integration with igneous petrology is key to linking monitoring data to underlying magmatic processes.

The triggering mechanism of the substorm onset has been a major issue in magnetospheric research. Various models have been proposed so far. To understand the causal relationship of magnetotail processes associ...

Abstract

The geodetic community commonly challenges the composite hypotheses in the statistical testing of mathematical models. Since the composite hypotheses are not specified as opposed to their simple counterparts, they require a prior estimation of the model parameters. However, if the mathematical models are ill-conditioned, the regularized estimation is often applied for the parameters of interest. Due to the biased property, the regularized estimation does not rigorously originate in the principle of maximum likelihood (ML) estimation, which was the base for developing the theory of the generalized likelihood ratio (GLR) test. Since the regularized estimator of the parameters of interest is consequently inconsistent with the ML one, one cannot construct the GLR test, which is the uniformly most powerful invariant (UMPI) test. So far, only the bias correction approach has been suggested to solve this problem. In this contribution, an implicit representation of the regularized mathematical model is proposed. It eliminates the complete impact of regularized estimation on a mathematical model and delivers the misclosures analytically free from the influence of regularization. Thus, one can construct the GLR test, which belongs to the UMPI family, and then formulate the test statistic in terms of misclosures.

Abstract

This short article highlights unsolved problems of magnetic reconnection in collisionless plasma. Advanced in-situ plasma measurements and simulations have enabled scientists to gain a novel understanding of magnetic reconnection. Nevertheless, outstanding questions remain concerning the complex dynamics and structures in the diffusion region, cross-scale and regional couplings, the onset of magnetic reconnection, and the details of particle energization. We discuss future directions for magnetic reconnection research, including new observations, new simulations, and interdisciplinary approaches.

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.

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.