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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

Pelagic calcifier proliferation along surface ocean gradients in carbonate chemistry

Nature Geoscience - Wed, 02/12/2025 - 00:00

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.

Global carbonate chemistry gradients reveal a negative feedback on ocean alkalinity enhancement

Nature Geoscience - Wed, 02/12/2025 - 00:00

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.

Nonlinear Resonant Interactions of Radiation Belt Electrons with Intense Whistler-Mode Waves

Space Science Reviews - Wed, 02/12/2025 - 00:00

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.

Magnetic Reconnection in Space: An Introduction

Space Science Reviews - Wed, 02/12/2025 - 00:00

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.

Rare-earth-rich rhabdophane

Nature Geoscience - Tue, 02/11/2025 - 00:00

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.

Signs of eruption decoded with petrology

Nature Geoscience - Tue, 02/11/2025 - 00:00

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.

Evolution of the near-Earth magnetotail associated with substorm onsets: revisiting the issues of onset timing and substorm triggering mechanism

Earth,Planets and Space - Tue, 02/11/2025 - 00:00

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...