In hydrological modelling, traditionally one calibration is performed over a certain calibration period before the model is used to study the hydrological system. This implies that a constant model structure and parameterization are assumed. However, if the catchment system is subject to changes that are not incorporated in the model, the parameter values found in a calibration period may not be optimal

Depth to water table (DWT) for an unconfined aquifer affects a wide range of hydrological, ecological, and agricultural problems such as soil salinization, plant type, and crop output. In nature conditions (without human impacts), DWT in shallow groundwater zones is mainly driven by evapotranspiration and precipitation. In real-world conditions, the human impacts on groundwater hydrological processes

Salt deposition has been encountered in near-wellbore regions of saline reservoirs during field-scale carbon dioxide (CO2) sequestration. To explain this phenomenon, pore-scale studies, mostly in the form of micromodel visualizations, have been previously implemented. However, there is limited knowledge about salt deposition and inherent dynamics in reservoir rocks. This study investigates and characterizes

Climate change has a significant impact on the runoff of basins in cold, dry areas. The quantification of regional ecohydrological responses to climate change such as warming and drought is essential for establishing proper water resource management schemes. We propose a simple and novel method based on the Budyko framework to evaluate the hydrologic resilience of 16 basins that conform the Asian Water

Parameter estimation has a high importance in the geosciences. The ensemble Kalman filter (EnKF) allows parameter estimation for large, time-dependent systems. For large systems, the EnKF is applied using small ensembles, which may lead to spurious correlations and, ultimately, to filter divergence. We present a thorough evaluation of the pilot point ensemble Kalman filter (PP-EnKF), a variant of the

We investigate the combined effects of network scale flow variability and retention due to matrix-diffusion on the scaling behavior of transport through fractured media. Two of the principal mechanisms controlling the transport of solutes through fractured low-permeability media are broad distributions of flow velocities and retention times in the solid matrix. We study the relative impact of these

Estimation of CO2 storage capacity in fractured porous reservoirs requires a better understanding of the CO2-water flow fundamentals in fracture-matrix systems. There are few core-flood experiments on three-dimensional CO2-water drainage in a fracture-matrix system, yet none have examined the impacts of the capillary continuity of fractures and fracture-matrix interactions. In this study, twelve drainage

Until recently, wave and hydrodynamic properties in the cross-shore direction have been linked to accretive or erosive morphological evolution. However, various uncertainties remain, hindering the full understanding and accurate prediction of the transport direction and quantity of sediment transport in nearshore areas. In this study, we showed that flash rip currents (FRCs) could significantly amplify

Riemann problems at geometric discontinuities are a classic and fascinating topic of hydraulics. In the present paper, the exact solution to the Riemann problem of the one-dimensional (1-d) Shallow water Equations at monotonic width discontinuities is completely determined for any initial condition. This solution is based on the assumption that the relationship between the states immediately to the

Snow and glaciers are important freshwater resources in the Himalayan catchments for all biological activities. However, under recent climate change, these resources are decreasing, thereby posing a serious threat to the future freshwater resources among the Himalayan catchments. Therefore, understanding the hydrological behaviour and sources of streamflow is necessary for better assessment, planning

An adaptive scheme for the sequential formulation of reactive transport involving two fluid phases is presented. Instead of solving the transport problem on the global fine-scale model, we decompose the domain into coarse gridblocks that are aggregates of fine gridblocks, and we define and solve transport problem on each of the coarse blocks. The details of the prolongation operator that allows for

Pore network model simulation (PNM) is an important method to simulate reactive transport processes in porous media and to investigate constitutive relationships between permeability and porosity that can be implemented in continuum-scale reactive-transport modeling. The existing reactive transport pore network models (rtPNMs) assume that the initially cylindrical pore throats maintain their shape

Three-dimensional (3D) natural convection (NC) processes in heterogeneous porous media and associated energy losses and mixing processes are still poorly understood. Studies are limited to two-dimensional domains because of computational burden, worsened by heterogeneity, which may demand grid refinement at high permeability zones for accurate evaluation of buoyancy forces. We develop a meshless Fourier

Capillary heterogeneity trapping caused by mesoscale heterogeneity at the millimeter scale has been shown to have a great potential in immobilizing a significant amount of CO2 in CO2 geologic storage. The goal of this study is to develop and apply a macroscopic percolation simulator to better understand how post-imbibition CO2 capillary heterogeneity trapping varies with different types and degrees

An integrated simulation-optimization modeling system (ISOMS) approach was developed for assessing adaptive strategies in response to coupled impacts of climate and landuse variations. The ISOMS can not only reflect future hydrological trends under changing environment, but also provide water-allocation plans under various uncertainties expressed as random or fuzzy feature systematically. A case study

The poultry industry plays an important role in meat production/supply, with a growth rate of more than 4% p.a. in the last few years. This white meat production requires a large amount of feed that increases competition in the use of natural resources for primary food and other uses. Grains are the primary source of poultry nutrition and oilseeds are the most common protein source, with maize, wheat

Multiphase mass and heat transfer are ubiquitous in the subsurface within manifold applications. The presence of fractures over several scales and complex geometry magnifies the uncertainty of the heat transfer phenomena, which will significantly impact, or even dominate, the dynamic transport process. Capturing the details of fluid and heat transport within the fractured system is beneficial to the

A coupled description of flow and thermal-reactive transport is spanning a wide range of scales in space and time, which often introduces a significant complexity for the modelling of such processes. Subsurface reservoir heterogeneity with complex multi-scale features increases the modelling complexity even further. Traditional multiscale techniques are usually focused on the accuracy of the pressure

Fluid-solid reactions play a key role in a large range of biogeochemical processes. Transport limitations at the pore scale limit the amount of solute available for reaction, so that reaction rates measured under well-mixed conditions tend to strongly overestimate rates occurring in natural and engineered systems. Although different models have been proposed to capture this phenomenon, linking pore-scale

Riverine floods are often caused by prolonged or heavy rainfall. These heavy or extreme rainfall events are mainly driven by various climate mechanisms, which have often been ignored in flood risk assessments. This study presents a climate mechanism-based flood frequency analysis approach, accommodating a direct linkage between risk metrics for decision making and the dominant causal climate mechanisms

Technologies that increase the accuracy of soil-moisture monitoring, such as in-situ sensors, have been proposed as a key solution for increasing agricultural water productivity. However, quantifying how uncertainty in soil-moisture estimates lead to irrigation inefficiencies or economic losses has not been explicitly studied. We develop a framework that combines a crop simulation model with a rule-based

Hydraulic properties of natural fractures are essential parameters for the modeling of fluid flow and transport in subsurface fractured porous media. The cubic law, based on the parallel-plate concept, has been traditionally used to estimate the hydraulic properties of individual fractures. This upscaling approach, however, is known to overestimate the fractures hydraulic properties. Dozens of methods

We evaluate the relative importance of the uncertainty related to parameters characterizing partially saturated groundwater flow on head and gravity changes associated with pumping tests taking place in homogeneous and heterogeneous porous media. We frame our study in a Global Sensitivity Analysis setting and assess the way imperfect knowledge of such parameters influences the probability distribution

Fresh groundwater reserves, being of vital importance for more than a billion of people living in the coastal zone, are being threatened by saltwater intrusion due to anthropogenic activities and climate change. High resolution three-dimensional (3D), variable-density (VD), groundwater flow and salt transport (FT) numerical models are increasingly being used to support water managers and decision makers

Subsurface porous formations provide large capacities for underground hydrogen storage (UHS). Successful utilization of these porous reservoirs for UHS depends on accurate quantification of the hydrogen transport characteristics at continuum (macro) scale, specially in contact with other reservoir fluids. Relative-permeability and capillary-pressure curves are among the macro-scale transport characteristics

Two-layer and multi-layer depth-averaged models have become popular for simulating exchange flows, seawater currents and geophysical flows. The partial differential equation systems associated with these models are similar to the single-layer shallow-water model. Yet, their eigenstructures are more complex owing to the pressure coupling between the layers. Such models occasionally lose their hyperbolic

Dealing with uncertainty in water resource planning is problematic because insufficient or underused infrastructure can have social and environmental costs. Multistage stochastic optimisation provides a mechanism to deal with this challenge in water supply capacity expansion planning. However, for real systems it can be mathematically hard and computationally expensive. The ‘Decision-rule’ formulation

Turbulent mixing is a key process influencing the dynamics of subaqueous gravity currents. In this study, the evolution of the local turbulent mixing dynamics along a lock-exchange gravity current propagating over a mild slope is statistically investigated by ensemble-averaging and spanwise-averaging 200 large eddy simulation results at two time steps characteristic of the slumping and inertial phases

Hydraulic tomography is a state-of-the-art method for inferring hydraulic conductivity fields using head data. We employed geostatistical inversion using synthetically generated head and flux data individually and jointly in a steady-state experiment. We designed 96 inversion scenarios to better understand the relative merits of each data type. For the typical case of a small number of observation

Enhanced weathering (EW) scenarios are analyzed using the model presented in Cipolla et al. (2020). We explore the role of different hydroclimatic forcing on carbon-sequestration efficiencies. We also investigate whether increasing soil carbon content improves weathering conditions. We link olivine weathering rates to pH variations and quantify the suitability of hydroclimatic regimes to EW, based

Consistent particle tracking relies on conforming velocity fields that ensure local mass conservation on elements. Cell-centered finite-volume and mixed finite-element methods result in conforming velocity fields but this is not the case for continuous Galerkin methods, such as the standard finite element method (FEM). Nonetheless standard FEM is often used for subsurface flow modeling because it yields

Although many frost heave and freezing soil models have been developed in the past decades, saturated conditions are commonly assumed and/or the behavior of pore ice rather than ice lenses are conventionally predicted. This study presents a fully coupled thermal-hydraulic-mechanical (THM) model for variably saturated freezing soil, which examines a number of processes. These include heat conduction

We combine modeling and measurements to investigate the dynamics of convective carbon dioxide (CO2) dissolution in a pressure-volume-temperature cell, extending a recent study by Wen et al. (J. Fluid Mech., vol. 854, 2018, pp. 56–87) at low-pressure under ideal-gas conditions to high-pressure and real-gas conditions. Pressure-dependent compressibility and solubility are included to model the evolution

One of the main challenges for India is increasing food security and promoting economic development using the domestic finite and already stressed natural resources. In the last decades silk production has been booming in India in response to the 2025 silk self-sufficiency goal set by the Indian Ministry of Textile. It is not clear to which extent mulberry (Morus alba), used to feed silkworm in 70%

The impacts of land cover change have traditionally been assessed in hydrological modeling with a priori knowledge, e.g., using methods based on the curve number, or by calibrating hydrological models over different time periods. However, how hydrological processes respond to such changes is extremely context-dependent. Thus, there is an opportunity for the development of hydrological models that can

Assessing the impacts of climate change on hydrologic regimes through hydrologic modeling is challenged by data uncertainty, predictor-selection uncertainty, and model uncertainty as well as their interrelationships. In this study, a Multi-level factorial ensemble data-driven hydrological model (MFEDHM) is developed to quantify the interactive, individual, and integrative impacts of multiple boundary

Relative permeability of supercritical CO2 (scCO2) and brine was determined in reactive and non-reactive rock cores using a combination of unsteady-state methodology and computed tomography. Experiments were conducted using a medical grade CT scanner to determine saturation using a custom Python script. The saturation and differential pressure across the core were then used to derive four empirical

Cellular Automata (CA) are particularly suitable for physically-based modelling of complex hydrological processes due to their inherent aptitude for parallel computing. Nevertheless, other CA specific features like asynchronism could be exploited to enhance further the computational efficiency. This note introduces an innovative activation/deactivation rule enabling for the first time the practical

Hydraulic parameters define the water retention, θ(ψ), and the unsaturated hydraulic conductivity, K(θ), functions. These functions are usually obtained by fitting experimental data using inverse modelling. The drawback of inverting the hydraulic parameters is that they suffer from non-uniqueness and the optimal hydraulic parameters may not be physical. To reduce the non-uniqueness, it is necessary

Multiphase displacements in porous media are expected to be stable if the injectant has a smaller mobility than the resident phase and injection velocity is small. We investigate two-phase displacements (aqueous phase displacing oleic phase) at favorable mobility ratios, which are expected to be stable, and find that the presence of low-viscosity irreducible water promotes the formation of viscous

Land cover change plays a critical role in influencing hydrological responses. Change in land cover has impacted runoff across basins with substantial human interference; however, the impacts in basins with minimal human interference have been studied less. In this study, we investigated the impacts of directional land cover changes (forest to/from combined grassland and shrubland) in runoff coefficient

At the local scale, artificial impounded reservoirs in dry regions exert influence on the surrounding local climate. Impounded reservoirs have been found to alter precipitation patterns and increase temperature, specific humidity and surface evaporation. The consequences of impoundment or its related climatic changes on the surrounding vegetation are still not well understood. We here examined the

The discrete fracture model (DFM) has been widely used to simulate fluid flow in fractured porous media. Traditional DFM is considered to be limited on conforming meshes, hence significant difficulty may arise in generating high-quality unstructured meshes due to the complexity of the fracture networks. Recently, Xu and Yang reinterpreted DFM and demonstrated that it can actually be extended to non-conforming

Water management by the impoundment of reservoirs has been found to influence evapotranspiration not only locally but also at the basin scale. Highly regulated hydrological basins generally show the effect of a net increase in evapotranspiration accompanying the successive impoundment of reservoirs. However, understanding and isolating the effect from a particular single impounded reservoir remains

Th geomechanical response of a porous reservoir due to injection of fluid can result from a complex interplay between the changes in porepressure and temperature near the wellbore. As a result, predictions are usually made using either simplified analytical models, which may apply unrealistic assumptions in order to produce a tractable model, or detailed numerical simulations that can be computationally

The bedload transport system of equations, composed by the two-dimensional shallow water equations for the free surface flow motion and the 2D Exner or bedload transport equation for the erodible bed layer, is used for a wide range of sediment transport processes in environmental surface flows. In this work, the numerical resolution has been implemented using improved and efficient versions of two

Subgrid modeling to account for unresolved topography within the context of shallow water equations relies on the use of coarse grids for computational efficiency. However, excessively coarse grids can lead to artificial cross flows between hydrologically disconnected areas separated by physical barriers smaller than the grid size. An approach based on introducing cell and edge clones, consisting of

Neural-network-based surrogate models are widely used to improve computational efficiency. Incorporating theoretical guidance into data-driven neural networks has improved their generalizability and accuracy. However, neural networks with strong form (partial differential equations) theoretical guidance have limited performance when strong discontinuity exists in the solution spaces, such as pressure

Two-dimensional shallow water models are widely used for flood risk assessment. Application of these models to large-scale urban areas significantly increases the computational cost as it requires high-resolution simulations to capture the complex hydrodynamic processes. Hence, simplified models that are based on local-inertial formulations have been proposed by different researchers. Although these

Fine temporal resolution streamflow records offer valuable information to further our understanding of watershed function. Among the many tools to decipher watershed processes, recession analysis can be used to gain insight into storage-discharge properties and watershed storage by analyzing portions of stream hydrographs whose behavior is attributed to the relationship between aquifer structure and

Enhanced Weathering (EW) resulting from soil amendment with highly reactive silicate minerals is regarded as one of the most effective techniques for carbon sequestration. While in laboratory conditions silicate minerals dissolution rates are well characterized, in field conditions the rate of the dissolution reaction is more difficult to predict, not least because it interacts with soil, plant, and

Observations show that instream vegetation has a strong impact on bedload transport. However, there is a scarcity of sediment transport predictors that directly account for the effects of plants, and existing methods, based on re-calculation of roughness coefficients, may present some inconsistencies. The approach herein proposed extends Einstein's parameters to include the effects of vegetation on

The dynamic pore-network modeling, as an efficient pore-scale tool, has been used to understand imbibition in porous media, which plays an important role in many subsurface applications. In this work, we aim to develop a dynamic pore-network model for imaged-based modeling of spontaneous imbibition in porous media. The µCT scanning of a porous medium of sintered glass beads is selected as our study