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Abstract

It is often accepted that the magnetic field structure of coronal mass ejections (CMEs) is accurately represented by the highly twisted circular cross-section magnetic flux rope model, which is the basis of all most commonly used sketches and representations of CMEs. This paradigm has been developed based on studies in the 1970s and 1980s, and it was the inspiration for a series of fitting models developed in the 1990s and 2000s to provide 3-D visualizations and representations for data obtained by remote sensing and in situ measurements. There has been a wealth of measurements since this paradigm was first developed, in particular numerous multi-point measurements and remote heliospheric observations of CMEs in addition to more physical models and numerical simulations. Taken together, they have demonstrated that such a paradigm, although it provides an explanation for certain CME signatures, is inadequate to represent the complexity of the magnetic field structure in numerous other cases. This manuscript reviews 40 years of continuous observations and ongoing research efforts since the proposal of the highly twisted circular cross-section flux rope model, and presents a more elaborate and realistic representation that better reflects the true complexity of the magnetic ejecta within CMEs.

The vast majority of earthquakes strike inside the Ring of Fire, a string of volcanoes and tectonic activity that wraps around the coastlines of the Pacific Ocean. But when an earthquake hits, the areas that experience the strongest shaking aren't always the places that suffer the greatest damage.

Even though "glacial" is commonly used to describe extremely slow, steady movement, a new study has found that glaciers speed up and slow down on a daily—even hourly—basis in response to changes in air temperature, rainfall and the tides.

An international team of climate scientists has found that dust brought to parts of Europe in 2022 from the Saharan desert was slightly radioactive, but its source was not from French nuclear bomb testing back in the 1960s. In their study, published in the journal Science Advances, the group tested dust samples from multiple sites in Europe.

Early detection of earthquakes could be vastly improved by tapping into the world's internet network with a groundbreaking new algorithm, researchers say.

The deepest regions of Earth's oceans, known as the abyssal and hadal zones, lie at least as far under the water's surface as Mount Rainier's peak rises above the land surface. These great depths of 4,000 or more meters make up one of Earth's least explored frontiers and are home to some of its most extreme environments and habitats.

Analysis of data from NASA radar aboard an airplane shows that the decades-old active landslide area on the Palos Verdes Peninsula has expanded.

A recent study by the Hong Kong University of Science and Technology (HKUST) has revealed a startling public health threat: About 17 million people are at risk of gastrointestinal problems due to excessive sulfate levels in groundwater. This alarming finding emerged from the world's first high-resolution global groundwater sulfate distribution map, launched by the university's School of Engineering.

Earth systems models are an important tool for studying complex processes occurring around the planet, such as those in and between the atmosphere and biosphere, and they help researchers and policymakers better understand phenomena like climate change. Incorporating more data into these simulations can improve modeling accuracy; however, sometimes, this requires the arduous task of gathering millions of data points.

The Greenland Ice Sheet is cracking open more rapidly as it responds to climate change. The warning comes in a new large-scale study of crevasses on the world's second largest body of ice.

Author(s): P. Hadjisolomou, T. M. Jeong, P. Valenta, A. J. Macleod, R. Shaisultanov, C. P. Ridgers, and S. V. Bulanov

The interaction of an ultra-intense laser with matter is an efficient source of high-energy particles, with efforts directed toward narrowing the divergence and simultaneously increasing the brightness. In this paper we report on emission of highly collimated, ultrabright, attosecond γ-photons and g…

[Phys. Rev. E 111, 025201] Published Mon Feb 03, 2025

Nature Geoscience, Published online: 03 February 2025; doi:10.1038/s41561-024-01636-6

Greenland-wide observations of crevasse volume and distribution suggest substantial increases in crevassing between 2016 and 2021 at marine-terminating sectors with accelerating ice flow.

SummaryThe Tibetan Plateau, a critical region influencing both local and global atmospheric circulation, climate dynamics, hydrology, and terrestrial ecosystems, is undergoing climate-driven changes, including glacial retreat, permafrost thaw, and groundwater changes. Despite its importance, implementing continuous and systematic observations have been challenging due to the area’s high altitude and extreme climate conditions. In this context, seismic interferometry emerges as a cost-effective method for the continuous monitoring of subsurface structural changes driven by environmental factors and internal geophysical processes. We investigate subsurface evolution using four years of seismic data from nine stations on the northeastern Tibetan Plateau, by applying coda wave interferometry across multiple frequency bands. Our findings highlight seismic velocity changes within the frequency bands 5–10 Hz, 0.77–1.54 Hz, and 0.25–0.51 Hz, revealing depth-dependent seasonal and long-term changes. Near-surface and deeper strata exhibit similar seasonal patterns, with velocities increasing in winter and decreasing in summer driven by changes in hydrological processes, while intermediate ice-water phase strata show contrasting behavior due to thermal elastic strain. Long-term trends suggest that the upper subsurface layer is affected by melting water and precipitation originating from Kunlun Mountains, whereas deeper layer reflect groundwater level variations influenced by climate change and human activities. This study provides insights into the environmental evolution of the Tibetan Plateau and its impact on managing local groundwater resources.

We conduct a series of numerical experiments of thermal convection of compressible fluids with temperature-dependent viscosity, in order to study how the adiabatic compression and model geometries affect the m...

Many studies have estimated crustal deformation from observed geodetic data. So far, because most studies have applied a smoothness constraint, which includes the assumption of local uniformity of a strain-rat...

New research reveals the surprising ways atmospheric winds influence ocean eddies, shaping the ocean's weather patterns in more complex ways than previously believed.

Constructed wetlands do a good job in their early years of capturing carbon in the environment that contributes to climate change—but that ability does diminish with time as the wetlands mature, a new study suggests.

The Earth's atmosphere has strengthened its ability to remove air pollutants, including the potent climate-warming gas methane, according to research published in Nature Communications.

The Kenyan rift system is prone to deformation due to various geological processes and human activities, such as overexploitation of groundwater and exploitation of geothermal energy. Crustal deformation monit...

A relatively small amount of groundwater trickling through Alaska's tundra is releasing huge quantities of carbon into the ocean, where it can contribute to climate change, according to new research out of The University of Texas at Austin.