Preprints
There are 7675 Preprints listed.
MilAMin in the browser: a million unknowns a minute in TypeScript and WebAssembly
Published: 2026-09-22
Subjects: Geophysics and Seismology, Numerical Analysis and Scientific Computing, Tectonics and Structure
In 2008 MILAMIN showed that a finite element code written in native MATLAB, a language then held to be too slow for large problems, could set up, solve and post-process one million unknowns per minute on a desktop, provided every stage of the pipeline gets equal care. This note brings the same pipeline to the web browser: Triangle meshing, 7-node Crouzeix-Raviart elements, supernodal Cholesky [...]
Early Hadean Earth conditions were ideal for prebiotic chemistry
Published: 2026-09-22
Subjects: Earth Sciences
The time at which surface conditions favorable for prebiotic chemistry were established on Earth remains debated. Following magma-ocean solidification, high atmospheric pressure modulated the release of water from Earth’s primary crust. Here, we model the coupled formation of early oceans and felsic crust under these conditions. Our calculations show that a hydrated primary crust forms, resulting [...]
National-scale mapping locates the mismatch between perceived and assessed flood risk in India
Published: 2026-09-22
Subjects: Environmental Indicators and Impact Assessment, Hydrology, Water Resource Management
Flood risk management assumes that people in hazardous places recognize the danger they face, but evidence on flood risk perception remains sparse in South Asia, home to much of the world's flood-exposed population. India has more than 600 million people exposed to inland flood hazards and the highest flood-related mortality in Asia, yet no national evidence base on flood risk perception. Here we [...]
From buffer-based tables to dynamic response curves for soil-specific lime requirement estimation using machine learning
Published: 2026-09-21
Subjects: Engineering, Life Sciences
Accurate estimation of lime requirement (LR) remains a major challenge in acid soils, as conventional buffer-based approaches, particularly the Shoemaker–McLean–Pratt (SMP) method, rely on a single equilibrium measurement and predefined target pH values, limiting their ability to capture the diversity of soil neutralization responses. This study evaluated whether machine-learning (ML) models can [...]
In-context learning for small-sample soil mid-infrared spectroscopy: evaluating TabPFN across an integrated soil-acidity panel
Published: 2026-09-21
Subjects: Engineering, Life Sciences
Soil acidity diagnosis requires several interdependent laboratory measurements, limiting throughput. Mid-infrared (MIR) spectroscopy can estimate this panel from one scan, but practical use depends on robust calibration. Deep learning has surpassed conventional methods in many data-rich fields; however, adapted deep learning architectures such as convolutional neural networks (CNNs) are [...]
Perceptions of Drought Risk Management in Zambia: Reflections from the Historic 2023/2024 Drought
Published: 2026-09-21
Subjects: International and Area Studies
Drought risk management depends not only on understanding the physical characteristics of drought but also on how drought is experienced, interpreted, and anticipated by affected institutions and communities. This study examines perceptions of drought and their implications for risk management in Zambia using the severe 2023/2024 drought as a case study. Guided by Taylor’s perception framework [...]
A response surface framework for persistence-aware lime requirement
Published: 2026-09-21
Subjects: Engineering, Life Sciences
Conventional lime-requirement (LR) methods estimate the dose needed to attain a target soil pH, but do not indicate how long the correction remains acceptable during re-acidification. We tested whether repeated dose–response measurements could provide a persistence-aware LR. Single applications of calcium carbonate (CaCO{\! }_{3}) and calcium oxide (CaO) were evaluated in clay, sandy loam, and [...]
Extreme Precipitation Indices Trends and Patterns in the Philippines
Published: 2026-09-20
Subjects: Atmospheric Sciences, Climate, Environmental Sciences, Meteorology
The Philippines experiences approximately 86% of its recorded disaster events from extreme precipitation, yet national-scale trend studies remain constrained by sparse station networks and narrow index coverage. This study mapped the spatial patterns and long-term trends of 12 extreme precipitation indices across the Philippine archipelago using 45 years of daily gridded precipitation data from [...]
Deep Learning to Infer Ocean Dynamics
Published: 2026-09-20
Subjects: Oceanography
Inferring ocean dynamics remains challenging due to the complexity of multiscale nonlinear interactions, sparsity of observations, and limitations of numerical models. Deep learning (DL) has emerged as a powerful data-driven framework that exploits nonlinear dependencies across heterogeneous datasets, complementing traditional approaches. Here, we review recent progress in applying DL to ocean [...]
Geodesic Location–Allocation for Liquefaction Investigation Coverage in Uttarakhand, India
Published: 2026-09-20
Subjects: Geographic Information Sciences, Geophysics and Seismology, Geotechnical Engineering, Operations Research, Systems Engineering and Industrial Engineering, Physical and Environmental Geography, Spatial Science
Site-scale liquefaction investigations in Uttarakhand are concentrated in the Roorkee–Haridwar and Rudrapur–Khatima corridors. This article asks a narrower, operational question: where should a limited reconnaissance programme investigate next to reduce geographic gaps in that evidence? Fifteen settlement-centred nodes were represented as a complete weighted graph, with four literature-supported [...]
Characterizing and Predicting Change in the Global Ocean Biosphere: A Four-Dimensional Observing Strategy for the 2028–2037 Decadal Survey
Published: 2026-09-19
Subjects: Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology
Ocean ecosystems constitute the largest habitable volume on Earth and regulate climate, support fisheries and a global Blue Economy valued at an estimated $1.5 trillion annually and provide services on which human wellbeing depends. Four decades of satellite ocean color observations have transformed understanding of phytoplankton distribution, biodiversity, and productivity, and NASA's PACE [...]
Topology-Aware Quality Control of Triangulated Terrain Models Using Local Euler Curvature and Elevation-Filtration Curves
Published: 2026-09-19
Subjects: Earth Sciences, Environmental Sciences, Geomorphology, Mathematics, Physical Sciences and Mathematics
Triangulated irregular networks (TINs) are widely used to represent topography and bathymetry, but their quali-ty control is usually dominated by geometric criteria such as minimum angle and aspect ratio, which do not test whether connectivity errors have changed the topology of the mesh. We present a topology-aware quali-ty-control framework based on a local Euler-curvature identity and on [...]
Was the Pre-Event SWIR Anomaly at Tsangbu Ri a Genuine Glacier-Collapse Precursor? A Calibrated Multi-Glacier Test of the 2026 Case
Published: 2026-09-19
Subjects: Applied Statistics, Geographic Information Sciences, Geology, Geomorphology, Glaciology, Hydrology, Planetary Geology, Planetary Glaciology, Remote Sensing, Spatial Science, Tectonics and Structure
On 26 August 2026 a compound bedrock-and-glacier failure on the northern flank of the Langtang Lirung–Tsangbu Ri (Kimshung) massif, Nepal–China border, generated a rock–ice avalanche and a catastrophic downstream flood along the Bhotekoshi–Trishuli river system. A pre-event Sentinel-2 shortwave-infrared (SWIR2–NIR–Red) composite (12 August 2026) shows a sharply bounded, strongly saturated [...]
Quantification of Power Plant NOx Emissions: A Reference for Diurnal and Seasonal Accuracy of TEMPO
Published: 2026-09-19
Subjects: Atmospheric Sciences, Remote Sensing
Satellite observations of NO2 from geostationary orbit provide an opportunity to study daytime emissions with hourly temporal resolution. We used NO2 column measurements from Tropospheric Emissions: Monitoring of Pollution (TEMPO) with a new fitting function, the rise-decay (RD) model, to derive NOx emissions at 64 power plants in the continental United States. The RD model separately fits the [...]
A One-Dimensional Framework for Three-Phase Flow in Immiscible and Near-Miscible CO2 Injection: Application to Enhanced Oil Recovery and CO2 Storage
Published: 2026-09-19
Subjects: Engineering
We develop an integrated analytical framework for one-dimensional three-phase flow - involving rarefaction waves, shocks generated through the elliptic region and shock locus, as well as water and oil banks - for the analysis of oil recovery and CO2 storage. The solutions are compared with numerical approximations from a commercial reservoir simulator and an explicit finite difference code, [...]