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As pandemic lockdowns forced humans into isolation, Earth's vegetation was thriving. The year 2020 was the greenest in modern satellite records from 2001 to 2020, according to a recent study published in Remote Sensing of Environment. Consistent growth in northern and temperate regions, combined with a brief period of tropical growth, primarily led to this remarkably verdant period.

The great ice streams of the Antarctic and Greenland are like frozen rivers, carrying ice from the massive inland ice sheets to the sea—and a change in their dynamics will contribute significantly to sea-level rise.

The amount of carbon dioxide (CO2) released by microbial decomposition of soil organic carbon on a global scale is approximately five times greater than the amount of anthropogenic CO2 emissions. Thus, it is essential to clarify the impact of climate change on soil CO2 release dynamics.

Polluted runoff is still smothering the Great Barrier Reef, our first national assessment of water quality trends in Australian rivers has revealed. The problem on the reef is getting worse, not better, despite efforts to improve farming practices and billions of dollars committed by governments to water-quality improvements.

Author(s): J. Gonzalez and J. Sheil

Already some years ago, Langdon [Phys. Rev. Lett. 44, 575 (1980)] proposed that inverse bremsstrahlung absorption in plasmas drives free electrons into non-Maxwellian distributions. Radiation-hydrodynamic simulations of plasma-based light sources, however, often (implicitly) assume Maxwellian-distri…

[Phys. Rev. E 111, L023201] Published Thu Feb 06, 2025

SummaryThe Makran Subduction Zone is a distinctive segment within the Alpine-Himalayan system, where one of the final remnants of the once-expansive Neo-Tethys Ocean is being subducted beneath the Eurasian Plate. Limited seismic data has left several questions unanswered about the structure of the subducting oceanic lithosphere, the transition from the wide and thick Makran accretionary prism to the Zagros Collision Zone, variations in sedimentary cover thickness along and perpendicular to the accretionary prism, and fluctuations in the thickness of sedimentary cover within the fore-arc Jaz Murian Depression (JMD). In this study, we utilize ambient-noise and earthquake surface wave tomography within a period range of 5–50 s to construct a high-resolution 3D shear-wave velocity model down to a depth of 60 km for the Iranian Makran and northern Oman. Using a new dataset from 65 seismic stations located in southeastern Iran and northern Oman, our analysis reveals a sharp velocity contrast within the oceanic lithosphere of the Gulf of Oman, just north of Muscat, with abnormally low-velocity oceanic lithosphere extending westward from this contrast, revealing subduction of a segmented oceanic lithosphere beneath the Makran. Our study finds no lithospheric-scale seismic velocity contrast along the ZMP fault, as usually thought as a transition boundary between the Zagros and Makran. Our velocity model shows that the wide accretionary prism of western Makran consists of two zones: a southern low-velocity zone associated with younger sediments and a northern high-velocity zone corresponding to older sediments. A considerable thinning of the sedimentary cover is observed east of longitude 59° E within the coastal Makran tectono-stratigraphic unit, aligning with the structural trend of the Pan-African Semail Gap Fault observed both onshore and offshore Oman. Additionally, a thick sedimentary basin is located beneath the eastern section of the JMD, with the thickness decreasing towards the west.

AbstractIn this paper we examine the dynamic pressure torque acting on a bumpy core-mantle boundary (CMB) at diurnal timescale in a frame tied to the planet. This torque possibly contributes to the CMB coupling constants determined from nutation observations and could affect the interpretation of these constants in terms of different CMB coupling mechanisms. We revisit the work of Wu and Wahr (1997) who have used seismic estimates for the topography at the CMB and computed the associated pressure torque effect on nutations. These authors showed that some topography wavelengths can lead to amplifications in nutations. For example, they found that the effects on the retrograde annual nutation can be at the milliarcsecond level for a degree-5 spherical harmonics of the topography. While Wu and Wahr (1997) only go up to degree 6 in their development in spherical harmonics and use a numerical technique, we go up to degree 20 and employ an analytical approach to solve the equations and to further study the Earth’s nutations. The approach is similar to the one we used for the effects of the pressure torque on the tidal variations of the length of day (LOD) (a companion paper, Puica et al., 2023). Unlike the numerical approach, this has the advantage of highlighting the mathematical dependencies between the different spherical harmonics involved in the development of the topographic torque and to highlight the frequency dependence of the results and thereby the possible resonances with inertial waves. By doing so, we can isolate and estimate the magnitude of the influence of each topographic coefficient on nutation. We show that only the core flattening may have an important role on nutation and that the other large wavelengths of the topography have a very small contribution, less than that obtained by Wu and Wahr (1997).

In a new paper published in Nature Geoscience, experts from Fraunhofer Heinrich-Hertz-Institut (HHI) advocate for the use of explainable artificial intelligence (XAI) methods in geoscience.

A new climate modeling study published in the journal Science Advances by researchers from the IBS Center for Climate Physics (ICCP) at Pusan National University in South Korea presents a new scenario of how climate and life on our planet would change in response to a potential future strike of a medium-sized (~500 m) asteroid.

Reducing sulfur in the air may inadvertently increase natural emissions of methane from wetlands such as peatlands and swamps, a new study has found.

Land topography is usually formed gradually over long periods of time, but sometimes a single event can dramatically change things. On New Year's Day in 2024, a devastating earthquake in the Noto Peninsula upended the region.

Africa is often synonymous with its drylands that cover two-thirds of the continent. Relief is brought through rainfall during the monsoon season, which is vital to help replenish water reserves for communities and wildlife alike. Now, the West Africa monsoon season runs from June through to September, while those in the east occur during March to May and October to December.

Nature Geoscience, Published online: 05 February 2025; doi:10.1038/s41561-025-01639-x

Uptake of explainable artificial intelligence (XAI) methods in geoscience is currently limited. We argue that such methods that reveal the decision processes of AI models can foster trust in their results and facilitate the broader adoption of AI.

Abstract

Since the Voyager mission flybys in 1979, we have known the moon Io to be both volcanically active and the main source of plasma in the vast magnetosphere of Jupiter. Material lost from Io forms neutral clouds, the Io plasma torus and ultimately the extended plasma sheet. This material is supplied from Io’s upper atmosphere and atmospheric loss is likely driven by plasma-interaction effects with possible contributions from thermal escape and photochemistry-driven escape. Direct volcanic escape is negligible. The supply of material to maintain the plasma torus has been estimated from various methods at roughly one ton per second. Most of the time the magnetospheric plasma environment of Io is stable on timescales from days to months. Similarly, Io’s atmosphere was found to have a stable average density on the dayside, although it exhibits lateral (longitudinal and latitudinal) and temporal (both diurnal and seasonal) variations. There is a potential positive feedback in the Io torus supply: collisions of torus plasma with atmospheric neutrals are probably a significant loss process, which increases with torus density. The stability of the torus environment may be maintained by limiting mechanisms of either torus supply from Io or the loss from the torus by centrifugal interchange in the middle magnetosphere. Various observations suggest that occasionally (roughly 1 to 2 detections per decade) the plasma torus undergoes major transient changes over a period of several weeks, apparently overcoming possible stabilizing mechanisms. Such events (as well as more frequent minor changes) are commonly explained by some kind of change in volcanic activity that triggers a chain of reactions which modify the plasma torus state via a net change in supply of new mass. However, it remains unknown what kind of volcanic event (if any) can trigger events in torus and magnetosphere, whether Io’s atmosphere undergoes a general change before or during such events, and what processes could enable such a change in the otherwise stable torus. Alternative explanations, which are not invoking volcanic activity, have not been put forward. We review the current knowledge on Io’s volcanic activity, atmosphere, and the magnetospheric neutral and plasma environment and their roles in mass transfer from Io to the plasma torus and magnetosphere. We provide an overview of the recorded events of transient changes in the torus, address several contradictions and inconsistencies, and point out gaps in our current understanding. Lastly, we provide a list of relevant terms and their definitions.

Information on geomagnetic field intensity in the past is essential for understanding the behavior and mechanism of the geodynamo. A fundamental unresolved problem of relative paleointensity (RPI) estimations ...

When people think about fiber optic cables, it's usually about how they're used for telecommunications and accessing the internet. But fiber optic cables—strands of glass or plastic that allow for the transmission of light—can be used for another purpose: imaging the ground beneath our feet.

Biochar, a charcoal-like material derived from plant biomass, has long been hailed as a promising tool for carbon dioxide removal. However, a new study by Stanford researchers highlights a critical issue: current methods for assessing biochar's carbon storage potential may significantly undervalue its true environmental benefits.

Computer models reveal how human-driven climate change will dramatically overhaul critical nutrient cycles in the ocean. In the Proceedings of the National Academy of Sciences, University of California, Irvine researchers report evidence that marine nutrient cycles—essential for sustaining ocean ecosystems—are changing in unexpected ways as the planet continues to warm.

С 17 по 21 февраля 2025 года в здании Президиума Российской академии наук (РАН, г. Москва, Ленинский проспект, 32А) состоится научная сессия-конференция Секции ядерной физики Отделения физических наук (ОФН) РАН "Физика фундаментальных взаимодействий", посвящённая памяти выдающегося всемирно известного российского физика-теоретика, академика РАН Валерия Анатольевича Рубакова.
На конференции планируется заслушать следующие пленарные доклады:

17 февраля 2025 г.

1. Сергеев А.М. (Национальный центр физики и математики (НЦФМ), г. Саров, Нижегородская обл.).Экстремальные световые поля.
2. Бутенко А.В. (Объединённый институт ядерных исследований (ОИЯИ), г. Дубна, Московская обл.). Установки проекта NICA.
3. Рябов В.Г. (ФГБУ "Петербургский институт ядерной физики им. Б.П. Константинова Национального исследовательского центра (НИЦ) "Курчатовский институт", г. Санкт-Петербург; Объединённый институт ядерных исследований, г. Дубна, Московская обл.). Эксперименты на ускорительном комплексе NICA.
4. Брагута В.В. (Объединённый институт ядерных исследований, г. Дубна, Московская обл.). Барионная материя при экстремальных условиях.

18 февраля 2025 года

5. Левичев Е.Б. (Институт ядерной физики им. Г.И. Будкера СО РАН, г. Новосибирск). Обзор перспективных ускорительных проектов для физики частиц.
6. Ольшевский А.Г. (Объединённый институт ядерных исследований, г. Дубна, Московская обл.). Изучение осцилляций нейтрино в ускорительных и реакторных экспериментах: результаты и перспективы/
7. Барабаш А.С. (Институт теоретической и экспериментальной физики имени А.И. Алиханова Национального исследовательского центра "Курчатовский институт", г. Москва). Масса нейтрино: прямые измерения и двойной бета-распад.
8. Алексеев И.Г. (Национальный исследовательский центр "Курчатовский институт", г. Москва). Поиск лёгких стерильных нейтрино.
9. Сюняев Р.А. (Институт космических исследований РАН, г. Москва; Max Planck Institute for Astrophysics, Garching, Germany). Результаты и перспективы миссии Спектр—Рентген—Гамма.

19 февраля 2025 года

10. Мурин Ю.А. (Объединённый институт ядерных исследований, г. Дубна, Московская обл.). Детекторные системы в релятивистской ядерной физике сегодня и завтра.
11. Образцов В.Ф. (Институт физики высоких энергий, НИЦ "Курчатовский институт", г. Протвино, Московская обл.). Последние результаты по распадам каонов.
12. Дружинин В.П. (Институт ядерной физики им. Г.И. Будкера СО РАН, г. Новосибирск). Изучение e+e− аннигиляции в адроны на коллайдерах ИЯФ.
13. Xiaorong Zhou (University of Science and Technology of China). The Project of Super Tau-Charm Factory in China.

20 февраля 2025 года

14. Сильченко О.К. (Московский государственный университет им. М.В. Ломоносова, Государственный астрономический институт им. П.К. Штернберга, г. Москва). Молодые галактики на красном смещении больше 9: новые данные и парадигма.
15. Быков А.М. (Физико-технический институт им. А.Ф. Иоффе РАН, г. Санкт-Петербург). Фотоны, нейтрино и космические лучи высоких энергий в нашей Галактике.
16. Кузнецов М.Ю. (Институт ядерных исследований РАН, г. Москва). Космические лучи с энергиями выше 1019 эВ: новые результаты и новые загадки.
17. Джилкибаев Ж.-А. М. (Институт ядерных исследований РАН, г. Москва). Астрофизические результаты Байкальского нейтринного телескопа.

21 февраля 2025 года

18. Кузьмичев Л.А. (Московский государственный университет им. М.В. Ломоносова, Научно-исследовательский институт ядерной физики им. Д.В. Скобельцына, г. Москва). Крупномасштабные детекторы для исследований космических излучений.
19. Никитенко А.Н. (Национальный исследовательский центр "Курчатовский институт", г. Москва; Imperial College, London, UK). Поиски Новой Физики за пределами Стандартной Модели на Большом Адронном Коллайдере.
20. Пешеходов Д.В. (Объединённый институт ядерных исследований, г. Дубна, Московская обл.). Последние результаты эксперимента NA64 в CERN.
21. Дудко Л.В. (Московский государственный университет им. М.В. Ломоносова, Научно-исследовательский институт ядерной физики им. Д.В. Скобельцына, г. Москва). Физика топ-кварка.

20 февраля 2025 года в рамках сессии-конференции "Физика фундаментальных взаимодействий" состоится мемориальная сессия, посвящённая научному наследию академика Валерия Анатольевича Рубакова.
Избранные доклады конференции, содержащие новые результаты, будут опубликованы в журнале "Ядерная физика".

The Pliocene epoch, which lasted from 5.3 million to 2.6 million years ago, was a consequential time in Earth's history. The Isthmus of Panama formed, connecting North and South America, and the accumulation of ice at the poles reshaped the world's biogeography.