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Heat waves have gotten hotter in the Northern Hemisphere in recent decades. Home to about 90% of the world's population, with the largest fraction living in the mid-latitudes, more frequent and more severe heat waves and droughts have occurred in the Northern Hemisphere—in Europe in 2003, 2010 and 2019, in North America during 2018 and 2021, and in eastern China in 2013 and 2022.

Author(s): William Trickey, T. J. B. Collins, I. V. Igumenshchev, V. N. Goncharov, and A. Shvydky

The dynamic-shell concept for inertial confinement fusion (ICF) uses an initially homogeneous target and a carefully shaped laser pulse to form a shell and implode it. The laser pulse consists of a series of pickets that drive shocks into the target. The first few shocks converge inwards and rebound…

[Phys. Rev. E 111, 025210] Published Fri Feb 28, 2025

Author(s): Yichen Fu, Justin R. Angus, Hong Qin, and Vasily I. Geyko

Coulomb collision is a fundamental diffusion process in plasmas that can be described by the Landau-Fokker-Planck (LFP) equation or the stochastic differential equation (SDE). While energy and momentum are conserved exactly in the LFP equation, they are conserved only on average by the conventional …

[Phys. Rev. E 111, 025211] Published Fri Feb 28, 2025

SummaryFaults exhibit dynamic weakening during large displacements (>1 m) at seismic slip velocities (>0.1 m/s), but the role of this weakening in small-displacement induced earthquakes (M 3–4), such as those in the Groningen Gas Field (the Netherlands), remains unclear. We conducted seismic slip-pulse experiments on Slochteren sandstone gouges (SSG) using a rotary-shear apparatus to investigate their dynamic behavior. Pre-sheared gouge layers, confined between ∼1.5 mm thick sandstone host blocks, were subjected to slip pulses at initial effective normal stresses of 4.9–16.6 MPa and pore fluid pressures of 0.1 and 1 MPa under undrained conditions. Slip pulses reached peak velocities of 1.8 m/s, accelerations up to 42 m/s², and displacements of 7.5–15 cm, using either dry Argon or water as pore fluid at ambient temperatures. Water-saturated gouges showed rapid weakening from a peak friction of ∼0.7 to ∼0.3, with early dilatancy followed by slower ongoing dilation. In contrast, Argon-filled samples exhibited only subtle weakening. Our findings confirm that water-saturated SSG weakens substantially during slip, with minimal dependence on normal stress, slip acceleration, or displacement, while dry samples do not. Microstructural analysis indicates no systematic relationship between PSZ width and frictional work or power input densities, suggesting that wear or heat production alone does not govern PSZ growth. Instead, thermal pore fluid pressurization, potentially involving water phase transitions at asperity scales, may drive weakening in short-displacement, induced seismic events.

A study led by UMass Dartmouth School for Marine Science & Technology (SMAST) Ph.D. student Siddhant Kerhalkar sheds new light on the recovery of ocean thermal structures following cyclone passage—an area of oceanography that has remained largely unexplored due to the scarcity of direct shipboard observations. This research enhances our understanding of how the ocean recovers after cyclones, which is essential for improving climate models and predicting extreme weather events.

A new downscaling method has been developed to generate high-resolution surface soil moisture (SSM) data for mountainous regions. By integrating land surface temperature (LST) and vegetation index (VI) data, this innovative technique enhances the spatial resolution of coarse satellite-based SSM products, correcting for topographic effects and providing accurate, seamless SSM maps. This advancement is poised to revolutionize hydrological studies, drought monitoring, and climate change research.

Beginning around 2.5 million years ago, Earth entered an era marked by successive ice ages and interglacial periods, emerging from the last glaciation around 11,700 years ago. A new analysis suggests the onset of the next ice age could be expected in 10,000 years' time.

Researchers led by Prof. Li Nuo from the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences have developed a method to simulate the concentrations of unmeasured geochemical elements in rock and stream sediment samples.

The coastline of Southeast Greenland is uplifting more rapidly than other parts of the island. This is caused by weak rocks beneath this part of Greenland, combined with the melting of the ice sheet, according to researchers.

Author(s): S. Werbowy, B. Pranszke, and L. Windholz

Studies of the static Stark effect are reported for the multiplets at 615.8, 645.6, 777.6, 822.4, 844.9, and 926.5 nm (vacuum wavelengths) of atomic oxygen, which are important for various applications. From the Stark patterns recorded at very high electric fields up to 780 kV/cm, we have determined…

[Phys. Rev. E 111, 025209] Published Thu Feb 27, 2025

The Fraser River is unique among the world's great rivers—a huge, relatively natural, undammed, mountain river running through a dense urban area.

Askoa Ibisate, a geographer specializing in fluvial geomorphology, has analyzed how the disappearance of the Olloki dam affects sediment transport. Ibisate concluded that the volume of pebbles mobilized by the demolition has increased, and their journey has been extended. The results are particularly significant because the monitoring work has been ongoing for seven years and the authorities are provided with valuable information for predicting the consequences of dam demolition. The work is published in the journal Geomorphology.

Publication date: Available online 15 February 2025

Source: Advances in Space Research

Author(s): Vladimir A. Srećković, Ljubinko M. Ignjatović, Milan S. Dimitrijević, Veljko Vujčić, Sanja Tošić, Felix Iacob

Publication date: Available online 15 February 2025

Source: Advances in Space Research

Author(s): Joshua O. Benjamin, Daniel I. Okoh, Babatunde A. Rabiu

Publication date: Available online 15 February 2025

Source: Advances in Space Research

Author(s): A.M. El-Taher, B.M. Habashy, M.A. El-Borie, A.A. Bishara, S.F. Ibrahim

Publication date: Available online 15 February 2025

Source: Advances in Space Research

Author(s): Xiaochen Ren, Biqiang Zhao, Lingqi Zeng, Honglian Hao, Zhipeng Ren, Bo Xiong

Earthquakes occur along fault lines between continental plates, where one plate is diving beneath another. Pressure builds between each plate, called fault stress. When this stress builds enough to release, the plates slip and grind against each other, causing an earthquake.

The nightmare scenario of Atlantic Ocean currents collapsing, with weather running amok and putting Europe in a deep freeze, looks unlikely this century, a new study concludes.

Imagine floating in space, gazing on a frozen white orb. The ball hangs in the void, lonely and gleaming in the light from its star. From pole to equator, the sphere is covered in a thick crust of ice. In orbit around the white planet is a single cratered moon.

A century of fire suppression, combined with global warming and drought, has led to increasingly destructive wildfires in the Western United States. Forest managers use tools like prescribed burns, thinning, mastication, and piling and burning to reduce fuel—live and dead trees, needles and leaves, and downed branches—that can feed intense wildfires. These methods aim to lower fuel levels, reduce crown density, and protect fire-resistant trees, fostering healthier, more resilient forests.