Integration of 2D Lateral Groundwater Flow into the Variable Infiltration Capacity (VIC) Model and Effects on Simulated Fluxes for Different Grid Resolutions and Aquifer Diffusivities

Better representations of groundwater processes need to be incorporated into large-scale hydrological models to improve simulations of regional- to global-scale hydrology and climate, as well as understanding of feedbacks between the human and natural systems. We incorporated a 2D groundwater flow model into the variable infiltration capacity (VIC) hydrological model code to address its lack of a lateral groundwater flow component. The water table was coupled with the variably saturated VIC soil column allowing bi-directional exchange of water between the aquifer and the soil. We then investigated how variations in aquifer properties and grid resolution affect modelled evapotranspiration (ET), runoff and groundwater recharge. We simulated nine idealised, homogenous aquifers with different combinations of transmissivity, storage coefficient, and three grid resolutions. The magnitude of cell ET, runoff, and recharge significantly depends on water table depth. In turn, the distribution of water table depths varied significantly as grid resolution increased from 1° to 0.05° for the medium and high transmissivity systems, resulting in changes of model-average fluxes of up to 12.3% of mean rainfall. For the low transmissivity aquifer, increasing the grid resolution has a minimal effect as lateral groundwater flow is low, and the VIC grid cells behave as vertical columns. The inclusion of the 2D groundwater model in VIC will enable the future representation of irrigation from groundwater pumping, and the feedbacks between groundwater use and the hydrological cycle.

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A near-global, high resolution land surface parameter dataset for the variable infiltration capacity model

Scientific Data ◽

10.1038/s41597-021-00999-4 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Jacob R. Schaperow ◽

Dongyue Li ◽

Steven A. Margulis ◽

Dennis P. Lettenmaier

Keyword(s):

Land Surface ◽

Global Scale ◽

Radiation Budget ◽

Soil Parameters ◽

Variable Infiltration Capacity ◽

Infiltration Capacity ◽

Vic Model ◽

Spatial Coverage ◽

Land Surface Parameter ◽

Vegetation Parameters

AbstractHydrologic models predict the spatial and temporal distribution of water and energy at the land surface. Currently, parameter availability limits global-scale hydrologic modelling to very coarse resolution, hindering researchers from resolving fine-scale variability. With the aim of addressing this problem, we present a set of globally consistent soil and vegetation parameters for the Variable Infiltration Capacity (VIC) model at 1/16° resolution (approximately 6 km at the equator), with spatial coverage from 60°S to 85°N. Soil parameters derived from interpolated soil profiles and vegetation parameters estimated from space-based MODIS measurements have been compiled into input files for both the Classic and Image drivers of the VIC model, version 5. Geographical subsetting codes are provided, as well. Our dataset provides all necessary land surface parameters to run the VIC model at regional to global scale. We evaluate VICGlobal’s ability to simulate the water balance in the Upper Colorado River basin and 12 smaller basins in the CONUS, and their ability to simulate the radiation budget at six SURFRAD stations in the CONUS.

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An evaluation of the importance of spatial resolution in a global climate and hydrological model based on the Rhine and Mississippi basin

10.5194/hess-2017-473 ◽

2017 ◽

Cited By ~ 1

Author(s):

Imme Benedict ◽

Chiel C. van Heerwaarden ◽

Albrecht H. Weerts ◽

Wilco Hazeleger

Keyword(s):

High Resolution ◽

Spatial Resolution ◽

Large Scale ◽

Climate Models ◽

Hydrological Cycle ◽

Global Climate ◽

Global Scale ◽

Global Climate Models ◽

Convective Processes ◽

Parameter Values

Abstract. The hydrological cycle of river basins can be simulated by combining global climate models (GCMs) and global hydrological models (GHMs). The spatial resolution of these models is restricted by computational resources and therefore limits the processes and level of detail that can be resolved. To further improve simulations of precipitation and river-runoff on a global scale, we assess and compare the benefits of an increased resolution for a GCM and a GHM. We focus on the Rhine and Mississippi basin. Increasing the resolution of a GCM (1.125° to 0.25°) results in more realistic large-scale circulation patterns over the Rhine and an improved precipitation budget. These improvements with increased resolution are not found for the Mississippi basin, most likely because precipitation is strongly dependent on the representation of still unresolved convective processes. Increasing the resolution of vegetation and orography in the high resolution GHM (from 0.5° to 0.05°) shows no significant differences in discharge for both basins, because the hydrological processes depend highly on other parameter values that are not readily available at high resolution. Therefore, increasing the resolution of the GCM provides the most straightforward route to better results. This route works best for basins driven by large-scale precipitation, such as the Rhine basin. For basins driven by convective processes, such as the Mississippi basin, improvements are expected with even higher resolution convection permitting models.

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Large-scale characteristics of the distribution of blowing-snow sublimation

Annals of Glaciology ◽

10.3189/172756408787814960 ◽

2008 ◽

Vol 49 ◽

pp. 11-16 ◽

Cited By ~ 5

Author(s):

Konosuke Sugiura ◽

Tetsuo Ohata

Keyword(s):

Northern Hemisphere ◽

Land Surface ◽

Large Scale ◽

Hydrological Cycle ◽

Analysis Data ◽

Global Scale ◽

Blowing Snow ◽

Scale Characteristics ◽

Global Datasets ◽

Northern And Southern Hemispheres

AbstractTo consider the large-scale characteristics of blowing-snow sublimation and its importance in the hydrological cycle in the cryosphere, we investigated the sublimation of blowing snow particles on a global scale using the global datasets of the European Centre for Medium-RangeWeather Forecasts (ECMWF) re-analysis data and the International Satellite Land Surface Climatology Project (ISLSCP) Initiative I data for 1987. The sublimation fluxes of blowing snow particles were estimated globally with 2.5˚ resolution at 6 hour intervals. We found that the sublimation of blowing snow particles occurs more widely in the Northern Hemisphere than in the Southern Hemisphere, does not increase monotonously with latitude, and becomes more active in the polar coast regions and highlands, although the annual mean sublimation fluxes of the Northern and Southern Hemispheres are almost equal. In addition, we confirmed the characteristic seasonal changes in the area of sublimation in the Northern Hemisphere. Although we need to incorporate continuous parameters from systematic ground-based studies of the structure of blowing snow in specific fields to reduce uncertainty regarding the characteristics of blowing snow, our results point to a need to review the current understanding of the hydrological cycle.

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Impact of climate change on groundwater : a global assessment with the CNRM climate models

10.5194/egusphere-egu21-9634 ◽

2021 ◽

Author(s):

Maya Costantini ◽

Bertrand Decharme ◽

Jeanne Colin

Keyword(s):

Climate Change ◽

Water Table ◽

Climate Models ◽

Hydrological Cycle ◽

Anthropogenic Impacts ◽

Global Climate ◽

Global Climate Model ◽

Global Scale ◽

Shallow Aquifers ◽

Mitigation And Adaptation

Groundwaters found in aquifers play an important role in the hydrological cycle and are essential for human activities and for natural ecosystems. They account for approximately one third of the human fresh water withdrawals and sustain ecosystems by supplying soil moisture during dry periods. Climate change will impact every components of the climate system and aquifers are no exception. Precipitation is the main driver of groundwater recharge and relatively shallow aquifers respond rather quickly to changes in the precipitation rates. Thus, climate change should have an impact on water table depths and could lead to water scarcity and food insecurity in some regions. Therefore, knowing the response of the aquifers to climate change is important to improve the development of mitigation and adaptation plans in water management.&#160;Here, the response of unconfined shallow aquifers to climate change is assessed at the global scale using the global climate model developed in our institute (CNRM) : CNRM-CM6 and CNRM-ESM2. We analyse simulations conducted for the Coupled Model Intercomparison Project 6 (CMIP6) following four pathways of greenhouse gas concentrations until 2100. The CNRM models are the only global climate models representing the physicals processes involving aquifers. Results show that aquifers should replenish at the global scale on average, which is consistent with the projected global intensification of precipitation. However, the evolution of water table depths is not uniform and presents large regional disparities. Additionally to climate change, anthropogenic impacts like intensive groundwater withdrawals for agricultural, domestic and industrial purposes should exacerbate the depletion in some aquifers basins. In order to identify these regions, the evolution of the water table depths is compared with the population density. This analysis highlights the widening risk of water stress in some already aquifer-dependant regions.

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Simulation of soil moisture for typical plain region using the Variable Infiltration Capacity model

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-368-215-2015 ◽

2015 ◽

Vol 368 ◽

pp. 215-220 ◽

Cited By ~ 1

Author(s):

Z. Wu ◽

Y. Mao ◽

G. Lu ◽

J. Zhang

Keyword(s):

Soil Moisture ◽

Large Scale ◽

Social Economy ◽

Moisture Distribution ◽

Variable Infiltration Capacity ◽

Infiltration Capacity ◽

Variable Infiltration Capacity Model ◽

Capacity Model ◽

Spatio Temporal ◽

River Plain

Abstract. Droughts have a severe impact on the development of the social economy in developed plain areas. Soil moisture is a good index, it can reasonably reflect changes in drought. In this study, Jiangsu province in the Yangtze River Plain was selected as the research region, and the VIC (Variable Infiltration Capacity) large-scale hydrological model was selected to simulate the daily soil moisture with a resolution of 0.125 × 0.125 degree from 1956 to 2009. The simulated soil moisture was verified by measured soil moisture. The results indicate that the simulated soil moisture distribution is relatively consistent for the three soil layers (0–20, 20−100 and 0–100 cm), showing an increasing trend from northwest to southeast. The simulated soil moisture anomalies agreed well with in situ observations. The simulated soil moisture data thus can be used to analyze the spatio-temporal variation of the regional water content and to provide support for drought monitoring and forecasting.

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Application of an improved global-scale groundwater model for water table estimation across New Zealand

10.5194/hess-2018-235 ◽

2018 ◽

Author(s):

Rogier Westerhoff ◽

Paul White ◽

Gonzalo Miguez-Macho

Keyword(s):

New Zealand ◽

Water Table ◽

Input Data ◽

Large Scale ◽

Hydraulic Head ◽

Global Scale ◽

Scale Model ◽

Catchment Scale ◽

Scale Models ◽

Model Equations

Abstract. Many studies underline the importance of groundwater assessment at the larger, i.e., global, scale. The large-scale models used for these assessments are often simplified and typically not used for smaller-scale, i.e., catchment-scale, studies, because hydrology and water policy are traditionally best constrained at the catchment scale, and because large-scale models are too uncertain for that scale. However, smaller-scale groundwater models can still have considerable uncertainty, especially in data-sparse areas. There is a potential for larger-scale models to constrain the uncertainty for small-scale models. That is because they can provide an extra source of information in data-sparse areas, such as the initial estimate of hydraulic head. Large-scale models, often quick and simple, can thus take away some of the computational burden of local and more sophisticated applications. The problem of this approach is that model uncertainty of large-scale models is often too large, because the quality of their, coarse and global-scale, input data is large, and often inconsistent with the input data of local models. What is needed is an approach where large-scale and local models can meet in the middle. This study uses an existing, global-scale, groundwater flow model. It feeds that model with national input data of New Zealand terrain, geology, and recharge. It then builds the first New-Zealand national-scale groundwater model. The resulting nationwide maps of hydraulic head and water table depths show that the model points out the main alluvial aquifers with fine spatial detail (200m grid resolution). The national input data and finer spatial detail result in better and more realistic variations of water table depth than the original, global-scale, model outputs. In two regional case studies in New Zealand, the hydraulic head matches the available groundwater level data well. The nationwide water tables show that the model is mostly driven by the elevation (gravity) and impeded by the geology (permeability). The use of this first New Zealand-wide model can aid in provision of water table estimates in data-sparse regions. The national model can also be used to solve inconsistency of models in areas of trans-boundary aquifers, i.e., aquifers that cover more than one region in New Zealand. Shortcomings of the model are caused by the simplified model properties, but also by the accuracy of input data. Future research should therefore not only focus on further improvements of model equations, but also improved estimation of hydraulic conductivity and the digital elevation model, especially in areas of shallow groundwater level. We further surmise that the findings of this study, i.e., application of a global-scale models at smaller-scales, will lead to subsequent improvement of the global-scale model equations.

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Potential for the Rapid Transport of Plutonium In Groundwater as Demonstrated By Core Column Studies

MRS Proceedings ◽

10.1557/proc-11-745 ◽

1981 ◽

Vol 11 ◽

Cited By ~ 2

Author(s):

D.R. Champ ◽

W.F. Merritt ◽

J.L. Young

Keyword(s):

Groundwater Flow ◽

Water Table ◽

Soil Column ◽

Column Studies ◽

Groundwater Flow Systems ◽

Cesium 137 ◽

Core Column ◽

Plausible Mechanism ◽

Rapid Transport ◽

Micro Organisms

The mobility of radionuclides in groundwater flow systems can be significantly altered by processes such as complexation, sorption on particulates, or hydrolysis, precipitation and the formation of colloids. Such processes provide potentially significant pathways for transport of radionuclides in the biosphere. Previous soil column studies demonstrated that radiocesium could be transported by particulates and that the process was likely mediated by micro-organisms. That observation provided a plausible mechanism to explain the anomalously rapid transport of small amounts of cesium-137 released from glass blocks buried below the water table at the Chalk River Nuclear Laboratories.

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The Variable Infiltration Capacity Model, Version 5 (VIC-5): Infrastructure improvements for new applications and reproducibility

10.5194/gmd-2018-36 ◽

2018 ◽

Author(s):

Joseph J. Hamman ◽

Bart Nijssen ◽

Theodore J. Bohn ◽

Diana R. Gergel ◽

Yixin Mao

Keyword(s):

Climate Modeling ◽

Source Code ◽

Model Development ◽

Global Scale ◽

Hydrologic Model ◽

Variable Infiltration Capacity ◽

Infiltration Capacity ◽

Data Set ◽

Vic Model ◽

Macro Scale

Abstract. The Variable Infiltration Capacity (VIC) model is a macro-scale semi-distributed hydrologic model. VIC development began in the early 1990s and the model has since been used extensively for basin- to global-scale applications that include hydrologic data set construction, trend analysis of hydrologic fluxes and states, data evaluation and assimilation, forecasting, coupled climate modeling, and climate change impact assessment. Ongoing operational applications of the VIC model include the University of Washington's drought monitoring and forecasting systems and NASA's Land Data Assimilation System. This paper documents the development of VIC version 5 (VIC-5), which includes a major reconfiguration of the legacy VIC source code to support a wider range of modern hydrologic modeling applications. The VIC source code has been moved to a public GitHub repository to encourage participation by the broader user and developer communities. The reconfiguration has separated the core physics of the model from the driver source code, where the latter is responsible for memory allocation, pre- and post-processing and input/output (I/O). VIC-5 includes four drivers that use the same core physics modules, but which allow for different methods for accessing this core to enable different model applications. Finally, VIC-5 is distributed with robust test infrastructure, components of which routinely run during development using cloud-hosted continuous integration. The work described here provides an example to the model development community for extending the life of a legacy model that is being used extensively. The development and release of VIC-5 represents a significant step forward for the VIC user community in terms of support for existing and new model applications, reproducibility, and scientific robustness.

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Flow simulation in karst regions from the scale of single aquifers to entire continents

10.5194/egusphere-egu2020-653 ◽

2020 ◽

Author(s):

Yan Liu ◽

Thorsten Wagener ◽

Andreas Hartmann

Keyword(s):

Groundwater Flow ◽

Large Scale ◽

Human Impacts ◽

Flow Simulation ◽

Global Scale ◽

Flow Index ◽

Catchment Scale ◽

Flow Models ◽

Continental Scale ◽

Flow Parameters

Large-scale hydrological models have been widely used for water resources management, such as studying human impacts (e.g., pumping and irrigation) on groundwater. Currently, most of these models do not explicitly include karst features for the recharge and groundwater simulations. However, the geological properties in karst regions substantially differ from non-karst areas, which makes recharge and groundwater flow behaviors distinctly different between the two types of systems. Due to challenges of combining karstic and non-karstic processes, of simulating inter-catchment groundwater flow, and of parameterizing karstification over large areas in karst regions, global karst groundwater flow models currently do not exist. In this study, we propose a general approach to integrate karstic and non-karstic processes and a hierarchical approach to confine the karstic groundwater flow parameters over large domains. First, we selected six karstic catchments (with different catchment sizes and climates) with adequate observations to test the combination of karstic and non-karstic simulations at the aquifer and catchment scale. We show that using system signatures helps to identify the necessary model structures and to integrate karstic and non-karstic processes. Second, we defined an Inter-catchment Groundwater Flow index (IGF) to quantitatively address groundwater flow crossing topographic boundaries. Third, we classify the level of karstification based on spring and catchment properties and evaluate different strategies for parameterization of karstic groundwater flow processes at varying degrees of karstification. Overall, our study provides a solid basis for a continental-scale karstic groundwater flow model, complementary to current global scale hydrologic modeling efforts where this process is still missing.

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The Variable Infiltration Capacity model version 5 (VIC-5): infrastructure improvements for new applications and reproducibility

Geoscientific Model Development ◽

10.5194/gmd-11-3481-2018 ◽

2018 ◽

Vol 11 (8) ◽

pp. 3481-3496 ◽

Cited By ~ 38

Author(s):

Joseph J. Hamman ◽

Bart Nijssen ◽

Theodore J. Bohn ◽

Diana R. Gergel ◽

Yixin Mao

Keyword(s):

Climate Modeling ◽

Source Code ◽

Model Development ◽

Global Scale ◽

Hydrologic Model ◽

Variable Infiltration Capacity ◽

Infiltration Capacity ◽

Vic Model ◽

Capacity Model ◽

Significant Step

Abstract. The Variable Infiltration Capacity (VIC) model is a macroscale semi-distributed hydrologic model. VIC development began in the early 1990s and the model has since been used extensively for basin- to global-scale applications that include hydrologic dataset construction, trend analysis of hydrologic fluxes and states, data evaluation and assimilation, forecasting, coupled climate modeling, and climate change impact assessment. Ongoing operational applications of the VIC model include the University of Washington's drought monitoring and forecasting systems and NASA's Land Data Assimilation System. This paper documents the development of VIC version 5 (VIC-5), which includes a major reconfiguration of the legacy VIC source code to support a wider range of modern hydrologic modeling applications. The VIC source code has been moved to a public GitHub repository to encourage participation by the broader user and developer communities. The reconfiguration has separated the core physics of the model from the driver source code, whereby the latter is responsible for memory allocation, preprocessing and post-processing, and input–output (I–O). VIC-5 includes four drivers that use the same core physics modules, but which allow for different methods for accessing this core to enable different model applications. Finally, VIC-5 is distributed with robust test infrastructure, components of which routinely run during development using cloud-hosted continuous integration. The work described here provides an example to the model development community for extending the life of a legacy model that is being used extensively. The development and release of VIC-5 represents a significant step forward for the VIC user community in terms of support for existing and new model applications, reproducibility, and scientific robustness.

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