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YOUNGDON CHOI

K-water & University of Virginia | Manager & Phd Student

Subject Areas: Hydrology

 Recent activity

ABSTRACT:

WRF-Hydro Singularity

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ABSTRACT:

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ABSTRACT:

This is an example of RHESSys Model on Coweeta subwatershed 18 on Rivanna which is University of Virginia HPC.
There are a model instance and source code in "rhessys_ws18_local.tar.gz".
Also, there is a jupyer notebook to explain how to simulate RHESSys model.

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ABSTRACT:

SUMMA (Clark et al., 2015a;b;c) is a hydrologic modeling framework that can be used for the systematic analysis of alternative model conceptualizations with respect to flux parameterizations, spatial configurations, and numerical solution techniques. It can be used to configure a wide range of hydrological model alternatives and we anticipate that systematic model analysis will help researchers and practitioners understand reasons for inter-model differences in model behavior. When applied across a large sample of catchments, SUMMA may provide insights in the dominance of different physical processes and regional variability in the suitability of different modeling approaches. An important application of SUMMA is selecting specific physics options to reproduce the behavior of existing models – these applications of "model mimicry" can be used to define reference (benchmark) cases in structured model comparison experiments, and can help diagnose weaknesses of individual models in different hydroclimatic regimes.

SUMMA is built on a common set of conservation equations and a common numerical solver, which together constitute the “structural core” of the model. Different modeling approaches can then be implemented within the structural core, enabling a controlled and systematic analysis of alternative modeling options, and providing insight for future model development.

The important modeling features are:

The formulation of the conservation model equations is cleanly separated from their numerical solution;

Different model representations of physical processes (in particular, different flux parameterizations) can be used within a common set of conservation equations; and

The physical processes can be organized in different spatial configurations, including model elements of different shape and connectivity (e.g., nested multi-scale grids and HRUs).

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ABSTRACT:

Examples of RHESSys and SUMMA Model Simulation on Coweeta subwatershed 18

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Resources
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Collection 0
Composite Resource 0
Generic 0
Geographic Feature 0
Geographic Raster 0
HIS Referenced Time Series 0
Model Instance 0
Model Program 0
MODFLOW Model Instance Resource 0
Multidimensional (NetCDF) 0
Script Resource 0
SWAT Model Instance 0
Time Series 0
Web App 0
Model Program Resource Model Program Resource
MODFLOW_USG Model
Created: Aug. 28, 2017, 8:08 p.m.
Authors: Sorab Panday · Motomu Ibaraki · Christian D. Langevin · Richard G. Niswonger · Joseph D. Hughes

ABSTRACT:

A version of MODFLOW, called MODFLOW-USG (for UnStructured Grid), was developed to support a wide variety of structured and unstructured grid types, including nested grids and grids based on prismatic triangles, rectangles, hexagons, and other cell shapes. Flexibility in grid design can be used to focus resolution along rivers and around wells, for example, or to subdiscretize individual layers to better represent hydrostratigraphic units.

MODFLOW-USG is based on an underlying control volume finite difference (CVFD) formulation in which a cell can be connected to an arbitrary number of adjacent cells. To improve accuracy of the CVFD formulation for irregular grid-cell geometries or nested grids, a generalized Ghost Node Correction (GNC) Package was developed, which uses interpolated heads in the flow calculation between adjacent connected cells.

MODFLOW-USG includes a Groundwater Flow (GWF) Process, based on the GWF Process in MODFLOW-2005, as well as a new Connected Linear Network (CLN) Process to simulate the effects of multi-node wells, karst conduits, and tile drains, for example. The CLN Process is tightly coupled with the GWF Process in that the equations from both processes are formulated into one matrix equation and solved simultaneously. This robustness results from using an unstructured grid with unstructured matrix storage and solution schemes.

MODFLOW-USG also contains an optional Newton-Raphson formulation, based on the formulation in MODFLOW-NWT, for improving solution convergence and avoiding problems with the drying and rewetting of cells. Because the existing MODFLOW solvers were developed for structured and symmetric matrices, they were replaced with a new Sparse Matrix Solver (SMS) Package developed specifically for MODFLOW-USG. The SMS Package provides several methods for resolving nonlinearities and multiple symmetric and asymmetric linear solution schemes to solve the matrix arising from the flow equations and the Newton-Raphson formulation, respectively.

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MODFLOW Model Instance Resource MODFLOW Model Instance Resource
MODFLOW-USG model of groundwater flow in the Wood River Valley aquifer system in Blaine County, Idaho
Created: Aug. 28, 2017, 9:19 p.m.
Authors: Jason C. Fisher · James R. Bartolino · Allan H. Wylie · Jennifer Sukow · Michael McVay

ABSTRACT:

A three-dimensional numerical groundwater flow model (MODFLOW-USG) was developed for the Wood River Valley (WRV) aquifer system, south-central Idaho, to evaluate groundwater and surface-water availability at the regional scale. The U.S. Geological Survey (USGS), in cooperation Idaho Department of Water Resources, used the transient groundwater flow model to simulate historical hydraulic head conditions from 1995 to 2010. This USGS data release contains all of the input and output files for the simulation described in the associated model documentation report (http://dx.doi.org/10.3133/sir20165080).

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Generic Generic
A Series of Test Cases for SUMMA
Created: April 3, 2018, 12:57 a.m.
Authors: Martyn Clark · Bart Nijssen · Jessica Lundquist · Dmitri Kavetski

ABSTRACT:

There are two classes of test cases :

1. TEST CASES BASED ON SYNTHETIC OR LAB DATA

- Synthetic Test Case 1: Simulations from Celia (Water Resources Research 1990)
- Synthetic Test Case 2: Simulations from Miller (Water Resources Research 1998)
- Synthetic Test Case 3: Simulations of the lab experiment of Mizoguchi (1990) as described by Hansson et al. (Vadose Zone Journal 2005)
- Synthetic Test Case 4: Simulations of rain on a sloping hillslope from Wigmosta (Water Resources Research 1999)

2. TEST CASES BASED ON FIELD DATA, AS DESCRIBED IN THE SUMMA PAPERS (CLARK ET AL., WATER RESOURCES RESEARCH 2015)

- Field Data Test Case 1: Radiation transmission through an Aspen stand, Reynolds Mountain East
- Field Data Test Case 2: Wind attenuation through an Aspen stand, Reynolds Mountain East
- Field Data Test Case 3: Impacts of canopy wind profile on surface fluxes, surface temperature, and snowmelt (Aspen stand, Reynolds Mountain East)
- Field Data Test Case 4: Form of different interception capacity parameterizations (no model simulations conducted/needed)
- Field Data Test Case 5: Snow interception at Umpqua
- Field Data Test Case 6: Sensitivity to snow albedo representations at Reynolds MountainEast and Senator Beck
- Field Data Test Case 7: Sensitivity of ET to the stomatal resistance parameterization (Aspen stand at Reynolds Mountain East)
- Field Data Test Case 8: Sensitivity of ET to the root distribution and the baseflow parameterization (Aspen stand at Reynolds Mountain East)
- Field Data Test Case 9: Simulations of runoff using different baseflow parameterizations (Reynolds Mountain East)

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Model Program Resource Model Program Resource
SUMMA 2.0.0 Sopron version (lubuntu-16.10)
Created: April 19, 2018, 11:25 p.m.
Authors: Martyn Clark · Bart Nijssen

ABSTRACT:

SUMMA (Clark et al., 2015a;b;c) is a hydrologic modeling framework that can be used for the systematic analysis of alternative model conceptualizations with respect to flux parameterizations, spatial configurations, and numerical solution techniques. It can be used to configure a wide range of hydrological model alternatives and we anticipate that systematic model analysis will help researchers and practitioners understand reasons for inter-model differences in model behavior. When applied across a large sample of catchments, SUMMA may provide insights in the dominance of different physical processes and regional variability in the suitability of different modeling approaches. An important application of SUMMA is selecting specific physics options to reproduce the behavior of existing models – these applications of "model mimicry" can be used to define reference (benchmark) cases in structured model comparison experiments, and can help diagnose weaknesses of individual models in different hydroclimatic regimes.

SUMMA is built on a common set of conservation equations and a common numerical solver, which together constitute the “structural core” of the model. Different modeling approaches can then be implemented within the structural core, enabling a controlled and systematic analysis of alternative modeling options, and providing insight for future model development.

The important modeling features are:

The formulation of the conservation model equations is cleanly separated from their numerical solution;

Different model representations of physical processes (in particular, different flux parameterizations) can be used within a common set of conservation equations; and

The physical processes can be organized in different spatial configurations, including model elements of different shape and connectivity (e.g., nested multi-scale grids and HRUs).

This version updated for the sopron workshop in Hungary(15~18 April, 2018)

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Model Program Resource Model Program Resource
SUMMA 2.0.0 Sopron version (lubuntu-16.04.4)
Created: May 11, 2018, 12:17 a.m.
Authors: Martyn Clark · Bart Nijssen

ABSTRACT:

SUMMA (Clark et al., 2015a;b;c) is a hydrologic modeling framework that can be used for the systematic analysis of alternative model conceptualizations with respect to flux parameterizations, spatial configurations, and numerical solution techniques. It can be used to configure a wide range of hydrological model alternatives and we anticipate that systematic model analysis will help researchers and practitioners understand reasons for inter-model differences in model behavior. When applied across a large sample of catchments, SUMMA may provide insights in the dominance of different physical processes and regional variability in the suitability of different modeling approaches. An important application of SUMMA is selecting specific physics options to reproduce the behavior of existing models – these applications of "model mimicry" can be used to define reference (benchmark) cases in structured model comparison experiments, and can help diagnose weaknesses of individual models in different hydroclimatic regimes.

SUMMA is built on a common set of conservation equations and a common numerical solver, which together constitute the “structural core” of the model. Different modeling approaches can then be implemented within the structural core, enabling a controlled and systematic analysis of alternative modeling options, and providing insight for future model development.

The important modeling features are:

The formulation of the conservation model equations is cleanly separated from their numerical solution;

Different model representations of physical processes (in particular, different flux parameterizations) can be used within a common set of conservation equations; and

The physical processes can be organized in different spatial configurations, including model elements of different shape and connectivity (e.g., nested multi-scale grids and HRUs).

This version updated for the sopron workshop in Hungary(15~18 April, 2018)

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Composite Resource Composite Resource
SUMMA&pySUMMA singularity
Created: July 5, 2018, 7:45 p.m.
Authors: YOUNGDON CHOI

ABSTRACT:

SUMMA & pySUMMA singularity

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Composite Resource Composite Resource

ABSTRACT:

This Composite Resource is the collection of Jupyter notebooks to demonstrate SUMMA TestCases that was tested at the Clark et al., (2015b) study in the Reynolds Mountain East catchment in southwestern Idaho.
JN-1: pySUMMA_ReynoldsAspennStand_StomatalResistance.ipynb (Fig7)
- The notebook demonstrates the impact of different stomatal resistance parameterizations on total evapotranspiration (ET)
JN-2: SummaModel_ReynoldsAspenStand_RootDistribution.ipynb (Fig8, left)
- The notebook demonstrates the impact of Root Distributions Parameters on total evapotranspiration (ET)
JN-3: SummaModel_Reynolds_Evapotranspiration.ipynb (Fig8, right)
- The notebook demonstrates the impact of Lateral Flow Parameterizations on total evapotranspiration (ET)
JN-4: SummaModel_Reynolds_runoff.ipynb (Fig9)
- The notebook demonstrates the impact of Lateral Flow Parameterizations on Basin-wide Runoff
JN-5: SummaModel_ReynoldsAspenStand_ShortwaveRadiation.ipynb (Fig1-above)
-The notebook demonstrates the impact of shorwave radiation Parameterizations of below canopy shorwave radiation
JN-6: SummaModel_ReynoldsAspenStand_ShortwaveRadiation_LAI.ipynb (Fig1-below)
- The notebook demonstrates the impact of LAI parameter values of below canopy shorwave radiation
JN-7-SummaModel_ReynoldsAspenStand_WindSpeed.ipynb (Fig2)
- The notebook demonstrates the impact of the canopy wind parameter for the exponential wind profile

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the impact of different stomatal resistance parameterizations on total evapotranspiration (ET) in the Reynolds Mountain East catchment in southwestern Idaho. This study applied three different stomatal resistance parameterizations: the simple soil resistance method, the Ball Berry method, and the Jarvis method.

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the impact of different stomatal resistance parameterizations on total evapotranspiration (ET) in the Reynolds Mountain East catchment in southwestern Idaho. This study applied three different stomatal resistance parameterizations: the simple soil resistance method, the Ball Berry method, and the Jarvis method.

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the sensitivity of different root distribution exponents (0.25, 0.5, 1.0). The sensitivity of evapotranspiration to the distribution of roots, which dictates the capability of plants to access water.

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the impact of the lateral flux of liquid water on total evapotranspiration (ET) using a SUMMA model for the Reynolds Mountain East catchment. This study looked at the sensitivity of the different model representation of the lateral flux of liquid water, which determines the availability of soil water.

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Collection Resource Collection Resource
Test Cases of SUMMA modeling that include model instances and Jupyter notebooks for SUMMA 2nd Paper(2015)
Created: Sept. 13, 2018, 6:51 p.m.
Authors: Martyn Clark · Bart Nijssen · Jessica Lundquist · Dmitri Kavetski · David E. Rupp · Ross Woods · Jim E. Freer · Ethan D. Gutmann · Andrew Wood · david gochis · Roy M. Rasmussen · David Tarboton · Vinod Mahat · Gerald N. Flerchinger · Danny G. Marks

ABSTRACT:

This resource aggregates several resources related to Test Cases of SUMMA Simulation on the Clark et al., (2015b)(https://doi.org/10.1002/2015WR017200) research. These Test Cases simulate SUMMA with pySUMMA which is a Python library for wrapping the SUMMA modeling framework. The resources include SUMMA Model Instances and notebooks to use pySUMMA. pySUMMA provides an object-oriented approach for manipulating Model Instance(configuration files), executing a SUMMA simulation on HydroShare and visualizing SUMMA model outputs.

A pySUMMA Simulation Procedure on HydroShare showing how these resources simulate is shown in the "pySUMMA Simulation Procedure on HydroShare" resource.

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Composite Resource Composite Resource

ABSTRACT:

pySUMMA Simulation Procedure Diagram depicting how to use pySUMMA on HydroShare with Jupyter notebooks and Model Instances.
This is the collection resources for Jupyter notebooks and Model Instances. (https://www.hydroshare.org/resource/1b7a9af74daa4a449190f922b5db366e/)

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the Impact of the canopy shortwave radiation parameterizations on below canopy shortwave radiation using a SUMMA model for the Reynolds Mountain East catchment. This study looked at four different canopy shortwave radiation parameterizations: BeersLaw method(as implemented in VIC), NL_scatter method(Nijssen and Lettenmaier, JGR 1999:NL 1999), UEB_2stream method(Mahat and Tarboton, WRR 2011:MT 2012), CLM_2stream method(Dick 1983)

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the Impact of the canopy shortwave radiation parameterizations on below canopy shortwave radiation using a SUMMA model for the Reynolds Mountain East catchment. This study looked at four different canopy shortwave radiation parameterizations: BeersLaw method(as implemented in VIC), NL_scatter method(Nijssen and Lettenmaier, JGR 1999:NL 1999), UEB_2stream method(Mahat and Tarboton, WRR 2011:MT 2012), CLM_2stream method(Dick 1983)

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the Impact of the canopy wind parameter for the exponential wind profile on simulations of below canopy wind speed at the aspen site in the Reynolds Mountain East catchment. This study looked at the impact of the Canopy wind parameter[0.10, 0.28, 0.50, 0.750] as used in the parameterization described by the exponential wind profile

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Model Instance Resource Model Instance Resource

ABSTRACT:

Following the procedure of Jupyter notebook, users can create SUMMA input using *.csv files. If users want to create new SUMMA input, they can prepare input by csv format. After that, users are able to simulate SUMMA with PySUMMA and Plotting with SUMMA output by the various way.

Following the step of this notebooks
1. Creating SUMMA input from *.csv files
2. Run SUMMA Model using PySUMMA
3. Plotting with SUMMA output
- Time series Plotting
- 2D Plotting (heatmap, hovmoller)
- Calculating water balance variables and Plotting
- Spatial Plotting with shapefile

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Model Instance Resource Model Instance Resource

ABSTRACT:

This SUMMA Model instance is a part of the Clark et al., (2015b) study, and explored the impact of the lateral flux of liquid water on Runoff using a SUMMA model for the Reynolds Mountain East catchment. This study looked at the sensitivity of the different model representation of the lateral flux of liquid water, which determines the availability of soil water.

Show More
Composite Resource Composite Resource

ABSTRACT:

Examples of RHESSys and SUMMA Model Simulation on Coweeta subwatershed 18

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Model Program Resource Model Program Resource
SUMMA 2.0.0 master version
Created: Dec. 7, 2018, 10:35 p.m.
Authors: Martyn Clark · Bart Nijssen

ABSTRACT:

SUMMA (Clark et al., 2015a;b;c) is a hydrologic modeling framework that can be used for the systematic analysis of alternative model conceptualizations with respect to flux parameterizations, spatial configurations, and numerical solution techniques. It can be used to configure a wide range of hydrological model alternatives and we anticipate that systematic model analysis will help researchers and practitioners understand reasons for inter-model differences in model behavior. When applied across a large sample of catchments, SUMMA may provide insights in the dominance of different physical processes and regional variability in the suitability of different modeling approaches. An important application of SUMMA is selecting specific physics options to reproduce the behavior of existing models – these applications of "model mimicry" can be used to define reference (benchmark) cases in structured model comparison experiments, and can help diagnose weaknesses of individual models in different hydroclimatic regimes.

SUMMA is built on a common set of conservation equations and a common numerical solver, which together constitute the “structural core” of the model. Different modeling approaches can then be implemented within the structural core, enabling a controlled and systematic analysis of alternative modeling options, and providing insight for future model development.

The important modeling features are:

The formulation of the conservation model equations is cleanly separated from their numerical solution;

Different model representations of physical processes (in particular, different flux parameterizations) can be used within a common set of conservation equations; and

The physical processes can be organized in different spatial configurations, including model elements of different shape and connectivity (e.g., nested multi-scale grids and HRUs).

Show More
Composite Resource Composite Resource

ABSTRACT:

This is an example of RHESSys Model on Coweeta subwatershed 18 on Rivanna which is University of Virginia HPC.
There are a model instance and source code in "rhessys_ws18_local.tar.gz".
Also, there is a jupyer notebook to explain how to simulate RHESSys model.

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Model Instance Resource Model Instance Resource
WRF-Hydro CyberGIS Test
Created: March 7, 2019, 9:58 p.m.
Authors: YOUNGDON CHOI

ABSTRACT:

aa

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Model Program Resource Model Program Resource
WRF-Hydro Singularity
Created: March 7, 2019, 10:12 p.m.
Authors: YOUNGDON CHOI

ABSTRACT:

WRF-Hydro Singularity

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