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Abstract

The Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) was proposed to the Chinese Academy of Science (CAS) and the European Space Agency (ESA) following a joint call for science missions issued in January 2015. SMILE was proposed by a team of European and Chinese scientists, led by two mission Co-PIs, one from China and one from Europe. SMILE was selected in June 2015, and its budget adopted by the Chinese Academy of Sciences in November 2016 and the ESA Science Programme Committee in March 2019, respectively. SMILE will investigate the connection between the Sun and the Earth using a new technique that will image the magnetopause and polar cusps: the key regions where the solar wind impinges on Earth’s magnetic field. Simultaneously, SMILE will image the auroras borealis in an ultraviolet waveband, providing long-duration continuous observations of the northern polar regions. In addition, the ion and magnetic field characteristics of the magnetospheric lobes, magnetosheath and solar wind will be measured by the in-situ instrument package. Here, we present the science goals, instruments and planned orbit. In addition the Working Groups that are supporting the preparation of the mission and the coordination with other magnetospheric missions are described.

Nature Geoscience, Published online: 27 January 2025; doi:10.1038/s41561-024-01637-5

Fire emissions in the Amazon and Cerrado biomes are mainly produced from smouldering combustion of woody debris, according to observationally constrained fire emissions inventories.

SummaryThe central Pamir plateau moves northward and collides into Eurasia at a rate that varies significantly over its 600 km-wide extension. However, the active structures accounting for such internal shear strain remain enigmatic. In this study, we use Interferometric Synthetic Aperture Radar (InSAR) data to investigate the coseismic and postseismic deformation of the ${M}_w6.9$ Sarez earthquake on 23 February 2023. Using a Bayesian framework, we find the most likely seismogenic fault geometry and explore the full solution space of slip distributions. Our results highlight the mainshock ruptures a nearly NNE fault dipping to the southeast. The finite-fault model exhibits a purely left-lateral strike-slip mechanism with little to no slip reaching the surface. Most of the coseismic slip remains confined to a depth of ∼5 to 20 km, consistent with a large shallow slip deficit. Postseismic afterslip, which decays rapidly within the month following the mainshock, cannot compensate for such coseismic shallow slip deficit. Integrating the analysis of coseismic slip, postseismic deformation, and regional seismic activity, we argue that in the central Pamir, significant north-south shear strain is accommodated along multiple parallel faults, often unmapped, hence posing a significant seismic hazard.

SummaryDetailed investigations of aseismic slow slip events (SSEs) are crucial for estimating the strain budget and SSE mechanisms within subduction zones. The Suruga Trough, which includes the Tokai seismic gap, is an important area in Japan from a hazardous perspective. However, the aseismic slip history of this trough following the 2011 Tohoku earthquake is difficult to determine as a result of post-seismic deformation caused by the earthquake. In this study, we provided detailed imaging of the interplate aseismic slip in the Suruga Trough after the 2011 Tohoku Earthquake by applying a network inversion filter to global navigation satellite system data and considering viscoelastic deformation and afterslip caused by the earthquake. The analysis revealed the 2012 Shima long-term SSE (l-SSE), 2013-2016 Tokai l-SSE, 2017-2020 Shima l-SSE, and 2023-2024 Atsumi+Tokai l-SSE, with the slip area expanding to the area adjacent to the Tokai seismic gap from July 2023, consequently changing the stress state to promote the anticipated Tokai earthquake. The findings of this study suggest that the recurrence interval of the Tokai slow slip ranges from 10 to 13 years, with a duration of approximately 4-5 years and a total magnitude ranging from 6.5 to 7.1. The l-SSE zone shows that the upper-limit temperature threshold, which is the temperature at the upper bound of the l-SSE zone aligning the 350°C isothermal line in the Tokai segment, does not hold in the Suruga Trough. The change in strike direction of the l-SSE zone suggests that a discontinuous factor controls the l-SSE occurrence, such as high pore pressure caused by fluid infiltration to the plate interface. Furthermore, we explored a gap between the short-term SSE (s-SSE) and l-SSE zones, and the findings indicated a non-continuous transition from l-SSE to s-SSE, thus providing insights into the discontinuous factors that regulate l-SSE and s-SSE generation. The recurrence interval (10–13 years) and duration (4-5 years) of the Tokai SSEs are long, and their moment rates (1015.8Nm/day) are low compared to those of the l-SSEs in other regions. The SSE parameters suggest that the scaling law may not apply to SSEs in the Suruga-Nankai Trough with the prolonged duration.

Antarctic krill swimming between the Southern Ocean's surface and seafloor depths, make a "surprisingly small" contribution to the carbon export "highway" compared to their fast-sinking feces, according to research published in Science.

A study led by The University of Western Australia has revealed new insights into the landscape profile of the Avon River Critical Zone Observatory in Western Australia.

A large international team of researchers with a wide variety of backgrounds has found evidence that carbon storage below seaweed farms can accumulate as much carbon as some Blue Carbon habitats. In their study published in Nature Climate Change, the group analyzed data from multiple seaweed farms around the globe.

Nature Geoscience, Published online: 24 January 2025; doi:10.1038/s41561-025-01640-4

The cause of episodes of unrest at caldera volcanoes is often unclear. Analysis of the sulfur composition of gas emissions at Campi Flegrei in Italy suggests a magmatic origin of the recent unrest at this hazardous caldera.

Nature Geoscience, Published online: 24 January 2025; doi:10.1038/s41561-024-01631-x

Biofilms on the surface of outdoor stone heritage contribute to either biodeterioration or bioprotection. We suggest that halting biofilm activity by limiting biologically available water shifts geomicrobiological development towards bioprotection.

Nature Geoscience, Published online: 24 January 2025; doi:10.1038/s41561-024-01632-w

The recent increase in isotopically light sulfur emissions from Campi Flegrei (Italy) is probably the result of degassing magma at ≥6 km depth and could be an indicator of caldera reawakening generally, according to observations and simulations.

Nature Geoscience, Published online: 24 January 2025; doi:10.1038/s41561-025-01638-y

Plant litter-derived mineral-associated organic matter that formed in the first year and pyrogenic organic inputs both persist on a decadal scale in grassland soil via distinct mechanisms, according to a soil organic matter decomposition experiment.

SummaryOn 9th January 2020, a Mw 6.4 earthquake struck the central Koryak Highlands of eastern Siberia, northeast of the diffuse triple junction between the North American, Pacific and Eurasian plates. The largest earthquake recorded in the central Koryak Highlands to date, it provides an excellent opportunity to study the little-known active tectonics of this remote, sparsely instrumented region. We mapped coherent, coseismic surface deformation with Sentinel 1 Interferometric Synthetic Aperture Radar (InSAR), making this one of the highest-latitude earthquakes to be captured successfully with satellite radar, in spite of the rugged, snow-covered terrain. Elastic dislocation modelling, teleseismic back-projections, calibrated hypocentral relocations, and teleseismic moment tensor solutions are used to resolve a left-lateral fault trending northwestwards, proximal but perpendicular to a regional geological suture zone, the Khatyrka-Vyvenka Thrust. The earthquake probably ruptured unilaterally northwestwards along a 20 km long segment that appears indistinct in the local topography, and likely generated no surface rupture. We interpret that these observations are indicative of a structurally immature fault zone and estimate a seismogenic zone thickness of 10–15 km. The Koryak Highlands earthquake illustrates how terrane boundaries within cordilleran belts may continue to accommodate tectonic strain long after accretion, resulting in significant earthquakes even along hidden faults.

Shallow coastal waters are hotspots for methane emissions, releasing significant amounts of this potent greenhouse gas into the atmosphere and contributing to global warming. New research highlights how tides, seasons, and ocean currents strongly influence methane emissions and how tiny microorganisms, called methanotrophs, help reduce their impact. These findings are part of a dissertation by NIOZ Ph.D. candidate Tim de Groot, which he will defend on January 31, 2025 at Utrecht University.

While firefighters work to extinguish the Los Angeles-area wildfires, city officials and emergency managers are also worried about what could come next.

By refining an artificial intelligence approach to predicting earthquakes in the laboratory, or labquakes, engineers at Penn State are paving the way to one day help forecast natural earthquakes.

Legend has it that a strange orb sometimes seen hovering over the railroad tracks in the remote area around Summerville, South Carolina, is a lantern borne by a ghost whose husband lost his head in a train accident.

Gravitationally induced deformation of the receiving unit of radio telescopes used for Very Long Baseline Interferometry (VLBI) distorts the observations and biases the deduced products. As this deformation ac...

Abstract

Spoofing detection is an essential process in global navigation satellite system anti-spoofing. Signal quality monitoring (SQM) methods have been widely studied as simple and effective means to detect spoofing. However, the disadvantages of the existing SQM methods, such as long alarm times and low detection rates, necessitate the study of new methods. Therefore, to address these challenges, this paper proposes a novel SQM method based on a long short-term memory-detect (LSTM-Detect) model with a strong capacity for sequential signal processing. In particular, this method evaluates the distortion of the autocorrelation function (ACF) by the trained LSTM-Detect model for spoofing detection. The simulation results demonstrate that the LSTM-Detect model can detect a wide range of spoofing signals, varying in signal power advantages, code phase differences, and carrier phase differences. In the Texas Spoofing Test Battery datasets 2–6, the detection rate exceeds 98.5%, with an alarm time of less than 5 ms. Compared with five existing SQM methods, the LSTM-Detect model exhibits a more comprehensive spoofing detection performance.

Abstract

Low-cost (LC) Global Navigation Satellite System (GNSS) receivers are argued as an alternative solution to geodetic GNSS counterparts for different applications. Single-frequency low-cost (SF-LC) GNSS receivers have been in the market for many years while their inability to acquire GNSS observations in second frequency limited their use. A few years ago, dual-frequency low-cost (DF-LC) GNSS receivers with enhanced capabilities entered the mass market, considering the advancements they have been tested and evaluated by many researchers. Lastly, multi-frequency low-cost (MF-LC) GNSS receivers become available. With the ability to track more satellite signals, these GNSS receivers are expected to obtain better overall performance. This review article aims to analyze recent advances and applications of LC GNSS receivers. To provide answers to the research question relevant articles were selected and analyzed. From the reviewed articles, it was concluded that the performance of SF-LC and DF-LC GNSS receivers is comparable to that of geodetic counterparts only in open-sky conditions. However, in adverse conditions, the differences become more highlighted. In such environments, SF and DF-LC GNSS receivers face challenges not only with positioning quality but also with their proper work. Limited studies on MF-LC receivers have reported comparable observations and positioning performance to geodetic GNSS receivers. Despite drawbacks, LC GNSS receivers have been successfully applied in surveying, mapping, geodetic monitoring, precision agriculture, navigation, atmosphere monitoring, Earth surface monitoring, and other fields.