Preprints
Filtering by Subject: Earth Sciences
Spatial Coupling of Greenhouse Gas Emissions, Vegetation Activity, Groundwater Nitrate Occurrence, and Soil Environments Across Denmark: A 5-km Spatial Association and Soil-Stratified Analysis
Published: 2026-09-14
Subjects: Earth Sciences, Environmental Sciences
Integrated environmental assessment increasingly requires the joint analysis of atmospheric emissions, vegetation dynamics, groundwater quality, and soil context rather than isolated thematic mapping. We developed a Denmark-wide 5-km analytical grid in EPSG:25832 containing 1,803 cells and harmonized four continuous environmental indicators: CO2 and CH4 emissions from EDGAR, vegetation activity [...]
Very-high-resolution optical imagery reveals key clues to the Langtang Lirung ice–rock avalanche
Published: 2026-09-14
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Ice–rock avalanches and resulting cascading processes are increasingly recognized to pose an exceptional risk to high-mountain systems. Once initiated, they often transition from dense multiphase mixtures to water-saturated debris flows and even hyper-concentrated floods, thus attaining sufficient runout potential to move from highly remote to populated regions. The event that originated from the [...]
Bounded at both ends: the detection window of routine 12-day C-band InSAR at rock–ice avalanche sources
Published: 2026-09-14
Subjects: Earth Sciences, Geomorphology
A negative result from satellite radar — "no precursory deformation was detected" — carries no information unless the range of signals the measurement could have detected is reported alongside it. We measure that range at two rock–ice avalanche sources, Langtang Lirung, Nepal (2026) and Ronti Peak, India (2021), using a single procedure, and identify four determinants of it that are site-specific [...]
From an everyday device to professional instrumentation. A framework for Portable Geoscience Learning Infrastructure and its illustrative application to ITA ARANDU MS
Published: 2026-09-13
Subjects: Earth Sciences, Geology
Geoscience education depends on practices that connect classroom learning with field settings: observing, locating, measuring, recording, comparing evidence, reasoning under uncertainty, and constructing interpretations. Digital fieldwork allows some of these practices to be undertaken with mobile devices, yet digital convenience, instrumental accuracy, and learning are not equivalent. This paper [...]
Thin the heat-trapping blanket of superpollutants and CO2 to slow the rate of warming by half
Published: 2026-09-13
Subjects: Earth Sciences, Other Earth Sciences
With the collapse of the Atlantic Meridional Overturning Circulation (AMOC) revealed as rate-dependent, it is critical to quickly cut the rate of warming in half, which would require an ambitious combination of fast mitigation of short-lived climate pollutants, CO2 mitigation, and removal of CO2 and other GHGs.
A proxy-based model of glacier thermal characteristics
Published: 2026-09-12
Subjects: Earth Sciences, Physical Sciences and Mathematics, Physics
This work presents a spatially lumped, computationally efficient model for estimating glacier thermal characteristics at a regional scale. We formulated proxies for the major englacial heat sources (meltwater refreezing and vertical shear strain heating) and heat transport mechanisms (downstream advection and vertical diffusion). We subsequently calculated these proxies for all glaciers in Alaska [...]
Assessment of global variations in the velocity–porosity relationship of marine sediments and rocks using the legacy data of scientific ocean drilling programs
Published: 2026-09-11
Subjects: Earth Sciences
The physical properties of sediments and rocks are routinely measured during scientific ocean drilling programs, as such data enable the recovered materials to be linked to geophysical observations and provide constraints on subseafloor lithology. However, lithological descriptions are not consistently linked to physical properties datasets for older drilling expeditions, thereby limiting global [...]
From data availability to evidence sufficiency. PIH MS as an auditable framework for diagnosing hydrogeological knowledge gaps in Mato Grosso do Sul, Brazil
Published: 2026-09-10
Subjects: Earth Sciences, Hydrology, Natural Resources Management and Policy
Groundwater registries can be extensive yet fail to demonstrate the evidence chain required to answer a hydrogeological question. We present PIH MS, an experimental framework that audits a bounded corpus of acquired records and makes knowledge gaps visible without predicting groundwater occurrence. The framework organises 12 evidence layers, nine knowledge dimensions, 39 declared requirement [...]
The explosive engine of the 2022 Hunga submarine eruption
Published: 2026-09-10
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Volcanology
The 2022 submarine eruption of Hunga volcano, Tonga, was among the largest volcanic eruptions in the modern era, yet the processes controlling its explosive sequence remain poorly understood. Here we present the first detailed insight into the internal mechanics of an explosive cycle from teleseismic waveforms. Four eruptive episodes repeat an implosion-explosion cycle, separated by a 3-minute [...]
Calibrated detection limits in routine Sentinel-1 products 50.6 hours before the Langtang Lirung rock–ice avalanche, Nepal
Published: 2026-09-09
Subjects: Earth Sciences, Geomorphology
On 26 August 2026 a rock–ice avalanche detached from Langtang Lirung, Nepal, and released a debris flood that crossed the Nepal–China border. Deformation preceding the failure has since been reported from a multi-month Sentinel-1 stack, and pre-event indications have been identified in commercial optical imagery. Both analyses began from a known failure location. This paper asks a different [...]
Revisiting the felsőbányaite-basaluminite question : nomenclatural synonymy and unresolved structural issues
Published: 2026-09-09
Subjects: Earth Sciences, Geochemistry, Mineral Physics, Soil Science
Felsőbányaite (1853) and basaluminite (1948) share the formula Al4(SO4)(OH)10·4H2O, and were shown to be crystallographically identical in 1997, leading the IMA to discredit basaluminite in 2006 in favor of the older name. This nomenclatural choice is not an issue. Instead, this opinion article explores a more focused contemporary question: is the poorly crystalline material that geochemists [...]
Lab-based X-ray imaging for accurate seismic velocity measurements at high pressure
Published: 2026-09-07
Subjects: Earth Sciences, Mineral Physics
A novel approach for accurately measuring the compressional (P) and shear-wave (S) velocities of materials at high pressure is demonstrated up to ~6 GPa using a Paris-Edinburgh press. Typically, accurate ultrasonic velocity measurements at high pressure require synchrotron facilities to image the sample length in-situ and to determine the internal cell pressure using X-ray diffraction from an [...]
Dendrochronology and the date of the Thera volcanic eruption
Published: 2026-09-07
Subjects: Earth Sciences, Glaciology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology, Volcanology
The main disciplines that contribute to our understanding of the chronology of the ancient Near East are history, archaeology, and various scientific dating techniques including dendrochronology, radiocarbon dating, and ice-core analysis. Beginning in the 1980s, a major rift began to develop between the historical-archaeological chronology and that based on dendrochronology-calibrated radiocarbon [...]
A rock-ice avalanche and the 2026 Bhote Koshi-Trishuli flood, Nepal
Published: 2026-09-06
Subjects: Earth Sciences
On 26 August 2026 a rock-ice avalanche in the Langtang Himal produced a debris flow and flood that destroyed the Rasuwagadhi-Gyirong border crossing within minutes and reached Devghat about six hours later. We reconstruct the cascade with a depth-averaged mixture-flow model constrained by the seismic origin time, a CCTV frame, gauge outages in the gorge and downstream stage records. The model [...]
No detectable precursor in Sentinel-1 backscatter before the 26 August 2026 Langtang Lirung rock–ice avalanche, Nepal
Published: 2026-09-06
Subjects: Earth Sciences, Geomorphology
On 26 August 2026 a rock–ice avalanche on the west flank of Langtang Lirung, Nepal, initiated a debris flow and flood that ran roughly 100 km down the Lhende Khola, Bhote Koshi and Trishuli. Several contemporaneous reports asserted that satellite radar had tracked a month of accelerating slope movement before failure. This note tests that claim in the amplitude record. Using Copernicus Sentinel-1 [...]