Preprints
Filtering by Subject: Hydrology
Impacts of a regional multi-year insect defoliation event on seasonal runoff ratios and instantaneous streamflow characteristics
Published: 2020-10-26
Subjects: Forest Sciences, Hydrology, Terrestrial and Aquatic Ecology, Water Resource Management
Repeated moderate severity forest disturbances can cause short- and long-term shifts in ecosystem processes. Prior work has found that stand-replacing disturbances (e.g., clear-cutting) increases streamflow in temperate forests, but streamflow responses to repeated moderate severity disturbances are more equivocal. This study examined a moderate disturbance caused by an unexpected population [...]
Modeling transpiration with sun-induced chlorophyll fluorescence via water use efficiency and stomatal conductance
Published: 2020-10-25
Subjects: Earth Sciences, Hydrology
Successfully applied in the carbon research area, sun-induced chlorophyll fluorescence (SIF) has raised the interest of researchers from the water research domain. However, the mechanism between SIF emitted by plants and transpiration (T) has not been fully explored. To improve the understanding of the relationship between SIF and T, we developed two SIF-T models, the WUE model and the [...]
A comprehensive study to understand the relationship of urbanization and population density with GRACE ΔTWS for selected study regions in India during 2003-2017
Published: 2020-10-24
Subjects: Environmental Indicators and Impact Assessment, Hydrology, Natural Resources and Conservation, Natural Resources Management and Policy, Planetary Hydrology, Remote Sensing, Sustainability, Water Resource Management
This work investigates the relationship between urbanization, population density and meteorological variables (temperature & precipitation) on groundwater storage in India during the period January'2003 to January'2017. Variations in groundwater storage have been analysed using Gravity Recovery and Climate Experiment (GRACE) derived variations of Terrestrial Water Storage (TWS). In the first part [...]
Modulation of riverine concentration-discharge relationships by changes in the shape of the water transit time distribution
Published: 2020-10-21
Subjects: Geochemistry, Hydrology
The concentrations of weathering-derived solutes in rivers and their co-variance with discharge are thought to reflect reactive-transport processes in hillslopes and to reveal the sensitivity of solute fluxes to climatic change. It is expected that discharge-driven changes in water transit times play some role in setting concentration-discharge (C-Q) relationships, but knowledge gaps remain. To [...]
River Planform Extraction From High-Resolution SAR Images Via Generalised Gamma Distribution Superpixel Classification
Published: 2020-10-21
Subjects: Computer Engineering, Electrical and Computer Engineering, Engineering, Geology, Geomorphology, Hydrology
The extraction of river planforms from remotely sensed satellite images is a task of crucial importance to many applications such as land planning, water resource monitoring or flood prediction. In this paper we present a novel framework for the extraction of rivers from Synthetic Aperture Radar (SAR) images, based on superpixel segmentation and subsequent classification. Superpixel segmentation [...]
A machine learning approach for prioritizing groundwater testing for per-and polyfluoroalkyl substances (PFAS)
Published: 2020-10-19
Subjects: Environmental Engineering, Environmental Health and Protection, Environmental Monitoring, Geochemistry, Hydrology, Risk Analysis, Water Resource Management
Regulatory agencies are beginning to recognize and regulate per-and polyfluoroalkyl substances (PFAS) as concerning environmental contaminants. In groundwater management, testing and mitigation strategies are desirable, but can be time and cost-intensive processes. As a result, only a fraction of all groundwater wells has been tested for PFAS levels, resulting in potentially extended drinking [...]
Uncertainties in Projected Rainfall over Brazil: The Role of Climate Model, Bias Correction and Emission Scenario
Published: 2020-09-01
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
The aim of this study is to answer four main questions: How well the Eta regional climate model simulates past precipitation over Brazil? What is the impact of bias correction on the reduction of model’s biases? What is the contribution of climate models, bias correction and emission scenarios to the total uncertainty of projected precipitation? And finally, what is the projected change in [...]
Quantification of non-linear multiphase flow in porous media
Published: 2020-08-20
Subjects: Earth Sciences, Engineering, Hydrology, Life Sciences, Medicine and Health Sciences, Mineral Physics, Physical Sciences and Mathematics
We measure the pressure difference during two-phase flow across a sandstone sample for a range of injection rates and fractional flows of water, the wetting phase, during an imbibition experiment. We quantify the onset of a transition from a linear relationship between flow rate and pressure gradient to a non-linear power-law dependence. We show that the transition from linear (Darcy) to [...]
Bedload transport in rivers: size matters but so does shape!
Published: 2020-08-16
Subjects: Earth Sciences, Geomorphology, Hydrology, Physical Sciences and Mathematics, Sedimentology
Bedload transport modelling in rivers, which defines the threshold for pebble movement, takes into account the size and density of pebbles, but does not formally consider particle shape. The lack of analyses evaluating the influences of shape and density on particle mobility presents a major deficiency. To address this issue and to compare the relative roles of the density and shape of particles, [...]
Variability of headwater stream network extents controlled by flow regime and network hydraulic scaling
Published: 2020-08-14
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Stream networks expand and contract through time, impacting chemical export, aquatic ecosystem habitat, and water quality. Although recent advances improve prediction of the extent of the wetted channel network (L) based on discharge at the catchment outlet (Q), controls on the temporal variability of L remain poorly understood and unquantified. Here we develop a quantitative, conceptual [...]
Hydrogeologic and Geochemical Distinctions in Salar Freshwater Brine Systems
Published: 2020-08-05
Subjects: Earth Sciences, Geochemistry, Hydrology, Physical Sciences and Mathematics
The Salar de Atacama contains one of the world’s most important lithium resources and hosts unique and fragile desert ecosystems. Water use issues of the hyper-arid region have placed it at the center of global attention. This investigation is the first robust assessment of a salar system to incorporate geology, hydrogeology, and geochemistry of the aquifer system in the inflow, transition zone [...]
Serious Gaming for Water Resources Planning and Hazard Mitigation
Published: 2020-08-03
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Education, Environmental Engineering, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Sustainability, Water Resource Management
Hydrological hazards lead to a broad range of socio-economic and environmental risks. The development of a resilient community and risk reduction heavily rely on the adoption of holistic watershed master planning whereby the adaptation options consider the risk associated with individual or multiple hydrological hazards occurring simultaneously at a specific location. Such planning approaches [...]
Visualizing the daily evolution and extent of snow drought
Published: 2020-07-22
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Natural Resources Management and Policy, Physical Sciences and Mathematics
Snow droughts are commonly defined as below average snowpack at a point in time, typically 1 April in the western United States. This definition is valuable for interpreting the state of the snowpack for resource management but obscures the temporal evolution of snow drought. Borrowing from dynamical systems theory, we applied phase diagrams to visually examine the evolution of snowpack [...]
Navigating groundwater model uncertainty analysis
Published: 2020-07-20
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
The design of a groundwater model is based on the model objective, the management or research question that the model seeks to address. Designing the uncertainty analysis of a groundwater models likewise needs to consider the objective of the uncertainty analysis; how the uncertainty in model predictions will be used. In this paper a framework is presented to consider the various dimensions of [...]
Tracking and measuring of clay shrinking and swelling using spaceborne remote sensing
Published: 2020-07-12
Subjects: Earth Sciences, Geophysics and Seismology, Hydrology, Physical Sciences and Mathematics
New capabilities for measuring and monitoring are needed to improve the shrink/swell hazard. A new French experimental site at Chaingy (Centre-Val de Loire) has been instrumented using extensometers at the surface and soil moisture sensors in the clay layer. Here we show by direct comparison between remote and in situ data for a period longer than three years that the vertical ground [...]