Preprints
There are 8049 Preprints listed.
Labels, Thresholds and the Reference Itself: Evaluating Sentinel-1 Flood Segmentation Against Copernicus EMS Maps, with a Preregistered Blind Test
Published: 2026-11-14
Subjects: Environmental Monitoring, Hydrology, Remote Sensing
Flood-segmentation models for Sentinel-1 synthetic aperture radar (SAR) are usually ranked by cross-validation on benchmark chips whose labels share sensors, dates and definitions with the model inputs. We measure how far such scores carry to operational reference maps, what limits them there, and whether adapting a model to the reference helps. The reference is Copernicus Emergency Management [...]
Embedding Probabilistic Pore Occupancy into Soil Hydraulic Models
Published: 2026-11-14
Subjects: Agriculture, Earth Sciences, Hydrology, Physical Sciences and Mathematics, Soil Science
Conventional soil hydraulic models describe unsaturated water retention and conductivity by assuming that water occupies the smallest pores, i.e., lower-energy pores. The author introduces a statistical pore occupancy framework to quantify the pore states by a pore distribution, retrieved from the retention function, allowing statistical inference of pore state conditions. The framework [...]
Anisotropy and redundancy governing undrained cyclic stress paths: closed-form modelling and micromechanical interpretation
Published: 2026-11-14
Subjects: Geotechnical Engineering
The undrained cyclic shear behaviour of sand leading to liquefaction cannot be predicted solely by traditional stress-dilatancy theories based on density and stress state; accounting for fabric, the microscopic structure of granular soils, is essential. This study develops a closed-form micromechanical model predicting increments in shear stress and mean effective stress during undrained cyclic [...]
Comparative Hydrodynamic Simulation and Field-Based Validation of an Extreme Urban Flood Event in Southern Bali
Published: 2026-11-13
Subjects: Engineering
A severe rainstorm on 9–10 September 2025 inundated Denpasar City, Badung Regency, and Gianyar Regency in South Bali, causing 15 fatalities across 188 reported locations. This study simulates the event over 14 sub-catchments (1,146 km²) with HEC-RAS 2D and compares two rainfall inputs: a lumped upstream boundary hydrograph based on Snyder’s synthetic unit hydrograph (Method A) and watershed-scale [...]
Deep oxygen status of Lake Geneva: a zombie lake or a prematurely pronounced death?
Published: 2026-11-13
Subjects: Earth Sciences, Environmental Sciences
Lake Geneva has become an emblematic example of a lake trapped in an apparent "zombie" state, where deep-water hypoxia persists despite decades of declining phosphorus concentrations. The persistence of oxygen depletion has largely been attributed to climate-driven reductions in deep winter mixing, assuming a limited responsiveness to successful nutrient management. The analysis of the 53-year [...]
SWOT Explorer: A browser extension for searching, previewing, clipping and quality-controlling SWOT satellite hydrology data
Published: 2026-11-13
Subjects: Education, Engineering
The Surface Water and Ocean Topography (SWOT) satellite measures the elevation and extent of rivers, lakes and reservoirs worldwide. Its river and lake products are distributed as one continent-wide file per satellite pass, so studying a single water body means downloading, unzipping and clipping many files with scripts or GIS software. SWOT Explorer is an open-source extension for Chrome and [...]
Uncertainty-aware deep learning for national lightning hazard and risk mapping to support sustainable disaster risk reduction in Bangladesh
Published: 2026-11-13
Subjects: Artificial Intelligence and Robotics, Atmospheric Sciences, Meteorology
Bangladesh has one of the world's highest lightning death tolls, borne mostly by farmers and fishers, yet national hazard maps rest on interpolation or tabular machine learning without independent validation. We developed a raster-native deep-learning framework reproducing monthly lightning stroke density from the WWLLN Global Lightning Climatology (WGLC, 2012-2025) on a 5-arc-minute grid from 18 [...]
Seismic evidence for a two-stage origin of the October 2026 Budhi Gandaki landslide in the Nepal Himalaya
Published: 2026-11-12
Subjects: Geomorphology, Geophysics and Seismology
On 10 October 2026 a rock avalanche left the south face of the Chamar massif, Nepal, ran 8.7 km down the Ungilung and dammed the Shyar above the Budhi Gandaki. Single-force inversions of one regional and 28 teleseismic records resolve four force pulses 23–26 s apart, alternating westward and eastward. Flow simulations released from the face favor two stages of failure, a smaller one at the onset [...]
Extensive Olivine Depletion in Archean Greenstone Belts: Evidence from Drill Core and Implications for Natural Hydrogen Generation
Published: 2026-11-12
Subjects: Earth Sciences, Geochemistry, Geology, Mineral Physics
Natural hydrogen models commonly assume that ultramafic rocks in Archean greenstone belts retain olivine for continued serpentinization, but the regional extent of preservation is poorly constrained. We analyze thermal-infrared mineral logs from 18,692 m of ultramafic drill core in 218 Western Australian boreholes. Olivine exceeds a defined spectral threshold in 97% of intrusion-hosted core but [...]
Seasonal-reference and regularization sensitivity with weak annual chlorophyll prediction
Published: 2026-11-12
Subjects: Life Sciences
Do bloom-phase heatwave exposures improve annual surface-chlorophyll anomaly prediction beyond a nutrient-aware baseline? We compare two historical seasonal-reference constructions on fixed lateryear evaluation cases, outcomes and inputs. The best pooled error on the original model and penalty grid is less than 4% below zero-anomaly prediction, which predicts the calibrated [...]
Knowledge graph and dataset of global storms (1990–2023)
Published: 2026-11-12
Subjects: Education, Engineering, Life Sciences, Medicine and Health Sciences, Physical Sciences and Mathematics, Social and Behavioral Sciences
From 1990 to 2023, storms accounted for 45.3% of recorded disaster damage and 18.2% of disaster deaths. Yet impact records do not say how strong a storm was where it struck, who was exposed or why a value is missing. This knowledge graph and dataset cover storms of eleven subtypes recorded in the Emergency Events Database from 1990 to 2023, in 1,595 country-years and 3,492 storm- country records. [...]
From Arctic UAS Reconnaissance to Planetary Rotorcraft Science: An evidence tracking workflow for linking aerial observations with ground investigation at FMARS
Published: 2026-11-12
Subjects: Geomorphology, Other Planetary Sciences
Aerial reconnaissance can place a ground target within its terrain context, but scientific interpretation requires a traceable connection between the image, its processing history, and the field record. This technical case study describes an evidence tracking workflow for imagery associated with the Flashline Mars Arctic Research Station on Devon Island, Canada. The available sources include [...]
Irrigation-driven land subsidence on the Barind Tract, northwest Bangladesh: two-track Sentinel-1 InSAR, GNSS-tied time series and spatially cross-validated explainable machine learning
Published: 2026-11-12
Subjects: Education, Engineering
The Barind Tract of northwest Bangladesh is the country’s most intensively groundwater-irrigated region, yet its ground motion has been measured only at isolated points. We processedascendinganddescendingSentinel-1small-baseline InSAR networks for 2017–2025, referenced them to a continuous GNSS station and converted line-of-sight rates to vertical velocity. In the ascending track, co herent land [...]
Activity-based excavation modelling in total Lagrangian SPH with pressure-dependent plasticity
Published: 2026-11-11
Subjects: Geotechnical Engineering, Numerical Analysis and Scientific Computing
We present an activity-based excavation model for underground mining simulations implemented within the total Lagrangian Smoothed Particle Hydrodynamics (TLSPH) framework of SoliDualSPHysics. The model introduces three key features: (1) a smooth cosine-based activity transition that gradually reduces the stiffness, mass, and gravitational loading of excavated particles; (2) a Drucker-Prager [...]
Adjoint measurement and calibration of Manning roughness in E3SM's river dynamical core
Published: 2026-11-11
Subjects: Physical Sciences and Mathematics
We present a transient discrete adjoint of RDycore, the river dynamical core of the Energy Exascale Earth System Model (E3SM), and use it to measure how much of a flood model's error its roughness parameter can remove. We differentiate the production solver in place rather than port it to a differentiable-programming framework: one exact, assembled shallow-water Jacobian serves the implicit [...]