Preprints
Filtering by Subject: Hydrology
Quantifying hydropower flexibility during extreme temperature events
Published: 2026-04-20
Subjects: Computational Engineering, Environmental Engineering, Hydraulic Engineering, Hydrology, Other Civil and Environmental Engineering, Other Mathematics, Power and Energy, Systems Engineering
Extreme weather events can impose substantial stress on the electrical grid. Hydropower offers unique operational flexibility, enhancing grid resilience and reliability. Despite this value of flexibility, systematic assessments of hydropower flexibility -- particularly during extreme events -- remain limited. This study is the first to quantify hydropower operational flexibility using 25 years' [...]
EXPLORATION OF WATER RESOURCES MANAGEMENT DECISION SUPPORT POTENTIAL IN DATA SCARCE WATERSHEDS AND ASSOCIATED DATA POLICY NEEDS
Published: 2026-04-18
Subjects: Bioresource and Agricultural Engineering, Computational Engineering, Environmental Monitoring, Hydrology, Natural Resources Management and Policy, Remote Sensing, Sustainability, Water Resource Management
Insufficient data access presents major challenges to scientific assessment of water resources, development of management plans, and attainment of water security. Hydrologic models are widely applied in the advisement of pollution, drought, and flood mitigation strategies; their accuracy relies on data used in setup and calibration. A case study of Sasumua River Watershed in Kenya illustrates [...]
How Would You Like Your SAR Flood Model? A Full-Stack, AI-Enabled Perspective on Operational Flood Mapping
Published: 2026-04-14
Subjects: Earth Sciences, Hydrology
Flood mapping with synthetic aperture radar (SAR) has long been framed primarily as a problem of improving inundation detection algorithms. That framing has produced major advances, but it increasingly understates what operational flood monitoring actually requires. In practice, useful flood products depend on the coordinated performance of data access, preprocessing, ancillary information, model [...]
Geostatistical Assessment of Shallow Groundwater Risk in Urban Coastal Virginia: A Case Study from Virginia Beach
Published: 2026-04-14
Subjects: Civil and Environmental Engineering, Engineering, Environmental Sciences, Geology, Hydrology, Life Sciences, Other Environmental Sciences, Water Resource Management
Urban groundwater assessments in coastal cities often rely on public monitoring datasets that are spatially uneven and temporally discontinuous. This study evaluates shallow groundwater risk in Virginia Beach, Virginia, using 30 years of records (1991–2020) from 121 monitoring wells for groundwater levels and 55 wells with groundwater‑quality data for chloride (Cl), iron (Fe), and manganese (Mn). [...]
Increasing Floods and Intensifying Droughts: The Future of Hydrological Extremes in a Warming Climate
Published: 2026-04-13
Subjects: Hydrology, Water Resource Management
Understanding how climate change alters the frequency and severity of hydrological extremes is critical for anticipating regional vulnerabilities and guiding adaptation. In this study, we analyze changes in the magnitude, intensity, and duration of extreme streamflow events, both floods and droughts, under RCP4.5 and RCP8.5 scenarios using the FutureStreams dataset. This dataset, driven by [...]
Lowering barriers to probing high-frequency variations in river chemistry through a frugal machine learning-based framework
Published: 2026-04-11
Subjects: Biogeochemistry, Environmental Monitoring, Hydrology, Water Resource Management
High-frequency river chemistry monitoring is crucial for capturing transient hydro-geochemical variations and ensuring water security, yet its implementation is limited by logistical and budgetary constraints. Here we present a machine learning-based framework that integrates continuous, low-cost physico-chemical proxies with sparse ‘anchoring’ solute measurements to reconstruct hourly-scale [...]
Inverse computational morphology of debris and alluvial fans
Published: 2026-04-09
Subjects: Geographic Information Sciences, Geomorphology, Hydraulic Engineering, Hydrology, Numerical Analysis and Scientific Computing
In mountain areas, debris flows and fluvial transport often build up conical deposits at the confluence between steep tributaries and trunk rivers. The resulting debris and alluvial fans typically exhibit a well-defined relationship between slope or elevation and the distance from the fan apex. This relationship, however, becomes more difficult to characterize when fans are constrained by the [...]
Simulation of Groundwater Flow To Evaluate Hydrogeologic Controls on a PFAS Plume, Coakley Landfill Superfund Site, Rockingham County, New Hampshire
Published: 2026-04-09
Subjects: Earth Sciences, Environmental Health and Protection, Environmental Sciences, Geology, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Per- and polyfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), have been detected at combined concentrations above 2,000 nanograms per liter (ng/L) at groundwater seep locations near the Coakley Landfill Superfund site, in North Hampton, New Hampshire. The landfill was active from 1972 to 1985. An impermeable cap was placed on the [...]
Multi-Sensor Monitoring of Wetland Inundation Using a Machine Learning and Data Fusion Framework
Published: 2026-04-04
Subjects: Applied Statistics, Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Statistics and Probability
Continuous, high-resolution inundation data are needed to understand how small-scale, short-term wetland flooding influences global methane emissions and carbon cycling. Small (less than 1,000 m²), variably inundated wetlands are significant methane sources, yet coarse satellite products often miss their dynamics. Integrating optical and radar imagery with resolutions less than 30 m offers a [...]
The Hermatz Effect: A Five-Layer Solar–Geo Dynamo Model for the Persistent 0.038 Hz Global Seismic Signal
Published: 2026-03-30
Subjects: Astrophysics and Astronomy, Atmospheric Sciences, Condensed Matter Physics, Earth Sciences, Environmental Chemistry, Fluid Dynamics, Geology, Geomorphology, Geophysics and Seismology, Hydrology, Meteorology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Astrophysics and Astronomy, Other Physics, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Planetary Hydrology, Tectonics and Structure, The Sun and the Solar System
Earth produces a faint but globally detectable vibration at a period of exactly 26 seconds, and no one has fully explained why. This paper proposes that it comes from a crack in the ocean floor off West Africa acting like a tuned whistle — the ocean blows air through it, the crack vibrates at its natural frequency, and the vibration travels around the entire planet as a seismic wave. Occasionally [...]
Spectral signatures in satellite soil moisture reveal irrigation patterns across the contiguous United States
Published: 2026-03-21
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Irrigation profoundly alters the terrestrial water cycle, yet its spatial distribution and temporal variability remain poorly constrained. Here, we introduce a new approach to detect irrigation in space based on spectral differences between modelled and satellite-observed soil moisture time series. Using wavelet decomposition, we isolate irrigation-induced variability at sub-annual scales by [...]
Do Less Predictable Tropical Cyclones Induce Larger Damages?
Published: 2026-03-17
Subjects: Atmospheric Sciences, Hydrology, Meteorology, Statistical Models
Tropical cyclones (TCs) cause substantial disaster losses worldwide. Forecast skill for TC track and intensity has been improved by enhanced observations, high-resolution numerical models, advanced data assimilation methods, and applications of machine-learning methods. Yet these improvements have not consistently translated into reduced losses, in part because disaster outcomes depend on many [...]
Probabilistic modelling of pharmaceutical pollution risk from sewage treatment work discharges using a Bayesian Network: application to a Scottish river catchment
Published: 2026-03-16
Subjects: Earth Sciences, Environmental Engineering, Environmental Monitoring, Environmental Sciences, Hydrology, Pharmacology, Toxicology and Environmental Health, Statistical Models, Statistics and Probability, Water Resource Management
Pharmaceuticals are increasingly recognised as a class of emerging contaminants of concern in rivers. Their continuous release from human use and variable removal in sewage treatment works (STWs) can produce ecologically relevant concentrations and contribute to antimicrobial resistance. We developed a probabilistic catchment-scale model based on a Bayesian Network (BN) to quantify pharmaceutical [...]
A terrain-aware approach for image-based urban flood monitoring
Published: 2026-03-12
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Water Resource Management
Urban nuisance flooding is widespread, yet quantitative observations of its magnitude and spatial variability remain limited. Most image-based approaches provide only relative measures of flooded image fraction, while quantitative methods require surveyed ground control and three-dimensional reconstruction. We introduce a terrain aware, perspective weighted framework that converts flooded image [...]
Slope-dependent riverbed strengthening and the evolution of the threshold for motion in gravel-bed rivers
Published: 2026-03-10
Subjects: Earth Sciences, Geomorphology, Hydrology
The threshold for motion exerts a fundamental control on sediment transport, channel morphology, and fluvial erosion. While channel slope and flow history are known to influence entrainment thresholds in gravel-bed rivers, their interaction has not been explored. We investigate how channel slope modulates riverbed strengthening during low-flow periods. Flume experiments were conducted across [...]