Preprints
Filtering by Subject: Hydrology
Impact of Hydrostratigraphic Continuity in Heterogeneity on Brine-to-Freshwater Interface Dynamics; Implications from a 2-D Parametric Study in an Arid and Endorheic Basin
Published: 2020-07-10
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Despite the prevalence of density-driven flow systems in brine-rich aquifers of arid climates and coastal aquifers, the impact of realistic geologic conditions remains poorly constrained regarding interface geometry in arid regions and time-sensitive density-dependent dynamics in brine-bearing aquifers in general. Salar de Atacama provides an analog for exploring interface dynamics in arid [...]
Post-Processing a Conceptual Rainfall-Runoff Model with an LSTM
Published: 2020-07-10
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics
Machine learning is becoming an increasingly important part of streamflow forecasting, but as these models to date lack a physical basis, there is a potential that they may produce values that are not realistic. We tested a simple post-processing strategy that uses the outputs from a calibrated conceptual model (the Sacramento Soil Moisture Accounting Model with Snow-17; SAC-SMA) as inputs into a [...]
GANSim: Conditional Facies Simulation Using an Improved Progressive Growing of Generative Adversarial Networks (GANs)
Published: 2020-07-06
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Earth Sciences, Geology, Hydrology, Mathematics, Physical Sciences and Mathematics, Sedimentology, Statistical Models, Statistics and Probability
Conditional facies modeling combines geological spatial patterns with different types of observed data, to build earth models for predictions of subsurface resources. Recently, researchers have used generative adversarial networks (GANs) for conditional facies modeling, where an unconditional GAN is first trained to learn the geological patterns using the original GANs loss function, then [...]
Exposure and vulnerability estimation for modelling flood losses to commercial assets in Europe
Published: 2020-07-06
Subjects: Earth Sciences, Hydrology, Multivariate Analysis, Physical Sciences and Mathematics, Statistics and Probability
Commercial assets comprise buildings, machinery and equipment, which are susceptible to floods. Existing damage models and exposure estimation methods for this sector have limited transferability between flood events. In this study we introduce two methodologies aiming at broader applicability: (1) disaggregation of economic statistics to obtain detailed building-level estimates of replacement [...]
Post-processing the National Water Model with Long Short- Term Memory Networks for Streamflow Predictions and Model Diagnostics
Published: 2020-07-02
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
We build three Long Short-Term Memory (LSTM) daily streamflow prediction models (deep learning networks) for 531 basins across the contiguous United States (CONUS), and compare their performance: (1) a LSTM post-processor trained on the U.S. National Water Model (NWM) outputs (LSTM_PP) as a target variable, (2) a LSTM post-processor trained on the NWM outputs and using atmospheric forcings [...]
Influences on Discharge Partitioning on a Large River Delta: Case Study of the Mississippi-Atchafalaya Diversion, 1926–1950
Published: 2020-07-02
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
The modern Mississippi River (M.R.) Delta is plumbed by the Mississippi and Atchafalaya rivers, setting water and sediment dispersal pathways for Earth’s fifth-largest river system. The Atchafalaya River’s (A.R.) partial annexation of discharge from the M.R., particularly between 1926 and 1950, prompted warnings of a rapid river avulsion and the construction of the Old River Control Structure to [...]
Geological Facies Modeling Based on Progressive Growing of Generative Adversarial Networks (GANs)
Published: 2020-06-22
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Earth Sciences, Geology, Geophysics and Seismology, Hydrology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Geological facies modeling has long been studied to predict subsurface resources. In recent years, generative adversarial networks (GANs) have been used as a new method for geological facies modeling with surprisingly good results. However, in conventional GANs, all layers are trained concurrently, and the scales of the geological features are not considered. In this study, we propose to train [...]
Potential environmental hazard due to tailings dam failure in Minnesota iron range and safety concern of the Dams in the US
Published: 2020-06-19
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
An ongoing debate centered around mining operations and tailings dam usage near the Minnesota mining range led to an investigation of potential environmental hazards near the cities of Hoyt Lakes and Embarrass. Topographic data from Satellite observations made available by USGS and HEC-RAS developed by US Engineer Corp are used to simulate the extent of mud flow from a hypothetical tailings dam [...]
Turbulent flow effects in a slickwater fracture propagation in permeable rock
Published: 2020-06-18
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Oil, Gas, and Energy, Physical Sciences and Mathematics, Volcanology
This work is devoted to an analysis of the near-tip region of a hydraulic fracture driven by slickwater in a permeable saturated rock. We consider a steady-state problem of a semi-infinite fracture propagating with constant velocity. The host rock is elastic and homogeneous, and fracture propagates according to linear elastic fracture mechanics. The fluid exchange between the fracture and [...]
The social-ecological dimensions of changing global freshwater availability
Published: 2020-06-18
Subjects: Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Sciences, Hydrology, Physical Sciences and Mathematics
Quantifying physical water security at the global scale remains hampered by a lack of systematically produced observational data. Here we combine the observed trends in global freshwater availability from the recently completed Gravity Recovery and Climate Experiment satellite mission1 with more than a dozen other global datasets and provide the missing observational basis to numerous existing [...]
Seasonal impact-based mapping of compound hazards
Published: 2020-06-17
Subjects: Applied Mathematics, Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Hydrology, Mathematics, Multivariate Analysis, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Statistics and Probability
Impact-based, seasonal mapping of compound hazards is proposed. It is pragmatic, identifies phenomena to drive the research agenda, produces outputs relevant to stakeholders, and could be applied to many hazards globally. Illustratively, flooding and wind damage can co-occur, worsening their joint impact, yet where wet and windy seasons combine has not yet been systematically mapped. Here, [...]
Mechanical Response of Shallow Crust to Groundwater Storage Variations: Inferences from Deformation and Seismic Observations in the Eastern Southern Alps, Italy
Published: 2020-06-05
Subjects: Earth Sciences, Geophysics and Seismology, Hydrology, Physical Sciences and Mathematics
Changes in continental water storage generate vertical surface deformation, induce crustal stress perturbations and modulate seismicity rates. However, the degree to which regional changes in terrestrial water content influence crustal stresses and the occurrence of earthquakes remains an open problem. We show how changes in groundwater storage, computed for a ~1000 km^2 basin, focus deformation [...]
Effect of Lateral Outflow on Three-Dimensional Flow Structure in a River Delta
Published: 2020-05-27
Subjects: Earth Sciences, Geomorphology, Hydrology, Physical Sciences and Mathematics
Spatial and temporal patterns in three-dimensional flow structure are linked to channel processes and morphology in many environments. However, there is not yet an understanding of how the flow structure is influenced by channelized and gradually distributed lateral outflows that are often prevalent in river deltas. This study presents an analysis of three-dimensional flow structure data [...]
Predictive modelling of envelope flood extents using geomorphic and climatic-hydrologic catchment characteristics
Published: 2020-05-26
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Hydraulic Engineering, Hydrology, Physical Sciences and Mathematics
A topographic index (flood descriptor) that combines the scaling of bankfull depth with morphology was shown to describe the tendency of an area to be flooded. However, this approach depends on the quality and availability of flood maps and assumes that outcomes can be directly extrapolated and downscaled. This work attempts to relax these problems and answer two questions: 1) Can functional [...]
UNSEEN trends: Detecting decadal changes in 100-year precipitation extremes
Published: 2020-05-26
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Climate, Earth Sciences, Engineering, Environmental Sciences, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Sample sizes of observed climate extremes are typically too small to reliably constrain non-stationary behaviour. To facilitate detection of non-stationarities in 100-year precipitation values over a short period of 35 years (1981-2015), we apply the UNprecedented Simulated Extreme ENsemble (UNSEEN) approach, by pooling ensemble members and lead times from the ECMWF seasonal prediction system [...]