Preprints
There are 7994 Preprints listed.
Advances in UAV-Based Methane Emission Monitoring: Sensors, Sampling Geometry, and Quantification
Published: 2026-10-30
Subjects: Engineering, Physical Sciences and Mathematics
Unmanned aerial vehicles (UAVs) are one key platforms for monitoring methane due to their flexible deployment with spatial scales between ground-based sensors and crewed aircraft This review synthesises research on UAV sensing technologies, flight and sampling strategies, quantification methods, and validation practices. It finds that quantitative performance depends on the combined choice of [...]
Where the Water Begins: A Field Guide to Six Streams Rising in the Knuckles Mountain Range, Sri Lanka
Published: 2026-10-30
Subjects: Hydrology, Physical and Environmental Geography, Water Resource Management
The Knuckles mountain range in central Sri Lanka is one of the wettest parts of the Mahaweli basin, and the streams that rise on its slopes feed the Victoria, Randenigala, Moragahakanda and Kalu Ganga reservoirs on which irrigation, hydropower and drinking water for a large part of the country depend. Walkers in the range meet these streams every day, yet there is no single account of where each [...]
Historical air quality database in Navarre, Spain (2011–2025): Harmonized hourly records and relational Star Schema of atmospheric pollutants
Published: 2026-10-30
Subjects: Atmospheric Sciences, Environmental Chemistry, Environmental Monitoring
Administrative air quality monitoring networks often release public data across fragmented repositories, variable formats, and inconsistent time encodings, hindering automated scientific re-use. This paper presents a curated, harmonized, and quality-controlled environmental dataset covering 15 consecutive years (2011–2025) of hourly atmospheric observations in Navarre, Spain. Integrating [...]
Conditional Benefits of Point-Level UAV LiDAR--Multispectral Fusion for 3D Vegetation Classification
Published: 2026-10-30
Subjects: Engineering, Environmental Monitoring
Multisensor remote-sensing fusion combines complementary measurements of landscape structure and surface reflectance, but adding a second modality does not necessarily produce uniform classification gains. This study evaluates point-level data fusion of unmanned aerial vehicle (UAV) LiDAR and multispectral imagery within a three-dimensional (3D) point-cloud representation. Tree--shrub [...]
Hotspots of Efficient Large-scale Circulation Response to Idealized Diabatic Heating
Published: 2026-10-30
Subjects: Atmospheric Sciences, Climate
Soil moisture anomalies can influence large-scale atmospheric circulation and thereby affect remote regions. However, the seasonal and geographical dependence of these circulation responses has been largely unexplored. Here, we conduct idealized experiments with a Linear Baroclinic Model, imposing identical low-level diabatic heating anomalies across global land to examine atmospheric circulation [...]
Prospectivity model for magmatic Nickel, Copper, Cobalt, and Platinum-Group Elements in the Midcontinent Rift
Published: 2026-10-30
Subjects: Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Volcanology
Much of the Midcontinent Rift is concealed beneath glacial sediment, which limits direct geological observation and makes it difficult to evaluate the potential for undiscovered magmatic Ni–Cu–PGE deposits with publicly available data. The 1.1 Ga rift hosts the Eagle Ni–Cu–PGE deposit of northern Michigan, one of the few domestic sources of nickel, a critical mineral of the United States. We [...]
Explainable and Uncertainty-Aware Computational Geodetic Inversion: A Review and Framework for Multi-Source Earth Observation
Published: 2026-10-30
Subjects: Artificial Intelligence and Robotics, Geophysics and Seismology, Numerical Analysis and Scientific Computing
Geodetic inversion converts surface and remote sensing data into estimates of concealed Earth system parameters, including fault slip, magma-source geometry, subsurface mass changes, crustal strain, and time-dependent geohazard activities. This review explores geodetic inversion as a computational challenge that involves combining diverse data, optimizing and quantifying uncertainty, and [...]
Constraining Lithospheric Delamination on Venus with Flexural Topography and Trench Geometry
Published: 2026-10-30
Subjects: Physical Sciences and Mathematics
Rollback-style lithospheric recycling has been proposed for a subset of Venusian coronae and other tectonic features based on the presence of trench-outer-rise systems, but the mechanism and conditions required to initiate recycling remain poorly understood. Peel-back delamination (PBD) is a proposed mechanism in which dense lithospheric mantle decouples and peels away from a thin layer of [...]
Spatiotemporal Variability of Aerosols over Ghana: Changes Associated with the COVID-19 Period
Published: 2026-10-30
Subjects: Environmental Sciences
Exposure to fine particulate matter (PM2.5) is a leading environmental health risk in West Africa, yet long-term characterization of aerosol variability in Ghana is constrained by sparse surface monitoring. Here we combine aerosol optical depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra and Aqua satellites (2010-2022), the daily, 1 km2 Gridded Africa Surface [...]
Droughts are dominated by anomalous circulation not anomalous atmospheric moisture content
Published: 2026-10-30
Subjects: Atmospheric Sciences, Climate
Agricultural drought is a sustained soil moisture deficit caused by reduced net moisture flux to the land surface. We show that agricultural droughts can occur when the atmosphere is anomalously wet, challenging the assumption that surface drying reflects atmospheric moisture deficits. Precipitation declines during drought even under increased atmospheric moisture, indicating low precipitation [...]
Treatment of Contaminated Water from the Oil Industry Using Electrocoagulation: A Bibliometric Analysis
Published: 2026-10-30
Subjects: Engineering
This review article presents a bibliometric analysis aimed at examining recent advances in the treatment of contaminated water from the oil industry using electrocoagulation (EC), evaluating the operational parameters that influence removal efficiency. A bibliometric analysis and a systematic review were conducted on 80 experimental articles (2021–2026) retrieved from Scopus. VOSviewer (threshold [...]
Assessment of SWOT Systematic Errors and Calibration Strategy
Published: 2026-10-30
Subjects: Physical Sciences and Mathematics
The SWOT KaRIN instrument provides wide-swath Sea Surface Height measurements affected by cross-swath systematic errors largely driven by thermo-elastic distortions and attitude knowledge errors. Using more than two years of science-orbit data, we evaluate a calibration procedure structured in two principal steps to estimate the systematic errors. The first step applies an empirical modeling [...]
Seasonal hydropower forecast framework using a combination of deep learning and physics-based methods
Published: 2026-10-30
Subjects: Engineering
Seasonal hydropower forecasts can inform power-system resource adequacy, but uncertainty propagates through climate, hydrologic, routing, water-management, and generation components.We develop a regional planning prototype linking North American Multi-Model Ensemble seasonal forecasts, Fourier Neural Operator (FNO) downscaling, an uncertainty-aware long short-term memory runoff model based on [...]
Dehydration of Serpentinized Ultramafic Rocks as a Candidate Deep Crustal Source of Natural Hydrogen and Hydrocarbons: Experimental Evidence from the Lesser Caucasus
Published: 2026-10-29
Subjects: Earth Sciences, Geology, Geophysics and Seismology
Natural hydrogen generated by serpentinization — the hydration of ultramafic rocks, in which ferrous iron is oxidised and molecular hydrogen is liberated from water — has recently been shown to proceed at rates of only 0.1 to 0.5 tonnes H₂ yr⁻¹ km⁻³ of reactive rock, implying that economically significant accumulations would require 10³ to 10⁴ years to develop [1]. A complementary process [...]
Late Paleocene leaf macroflora from a destroyed outcrop of the Marcelina Formation, Paso Diablo Mine, Venezuela: a rescue record
Published: 2026-10-29
Subjects: Earth Sciences, Geology, Other Plant Sciences, Paleobiology, Paleontology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
In 2016, a production blast at a mining face of the Paso Diablo Mine (Guasare Basin, northwestern Venezuela) exposed a level rich in fossil leaves of the Marcelina Formation (late Paleocene), located between coal seams 4O and 4M. The material was removed as overburden by a mining shovel a few hours after it was documented. We present the first published record of leaf macroflora from this [...]