Difference between revisions of "Project File:Infiltration – Optional"

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(→‎3.6.4.4 Optional Output)
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! Card !! Argument !! Description
 
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| <pre>IN_THETA_LOCATION  "filename.ext"</pre> || ''file name'' || Input ASCII file that contains locations of cells to output time series moisture data.
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| <pre>IN_THETA_LOCATION  "filename.ext"</pre> || ''file name'' || Input ASCII file that contains locations (row col) of cells to output time series moisture data. Works with all infiltration types '''GREEN_AMPT''' '''INF_REDIST''' '''INF_LAYERED_SOIL''' '''INF_RICHARDS'''.  Output is time series of soil moisture for each location. If doing '''LONG_TERM''' simulations, output is time series of soil moisture for each soil layer in your soil moisture model.  The number of layers is dependent on how you have set up your soils.  Output will be listed in the same order as the inputs.  There will be one column for each soil layer for each output location.  For '''INF_REDIST''' and '''INF_LAYERED_SOIL''' there will be two columns for each location.  If there is only one soil layer in your model, then the second column for each location will have a no data card, -999.99.  If you are simulating groundwater and the groundwater overtakes a layer at a location, you will get a no data card (-999.999) while that layer at that location is under the groundwater.  If you are not doing long term simulations, only the surface soil moisture is listed, so only one column per location.  If simulating '''INF_RICHARDS''' then there is output for every RE cell in the soil column for each output location.  As the number of cells in the RE solution can vary both spatially and temporally (when simulating groundwater), the number of output columns can vary over time.  For this reason, results from RE may be most useable if output only one location at a time.   
 
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| <pre>OUT_THETA_LOCATION  "filename.ext"</pre> || ''file name'' || Filename to output time series moisture data every '''HYD_FREQ''' time steps at cells specified in '''IN_THETA_LOCATION'''.
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| <pre>OUT_THETA_LOCATION  "filename.ext"</pre> || ''file name'' || Filename to output time series moisture data every '''HYD_FREQ''' time steps at cells specified in '''IN_THETA_LOCATION'''. Output is listed in same order as input.  Output is time series of soil moisture for each location. If doing '''LONG_TERM''' simulations, output is time series of soil moisture for each soil layer in your soil moisture model.  The number of layers is dependent on how you have set up your soils.  Output will be listed in the same order as the inputs.  There will be one column for each soil layer for each output location.  For '''INF_REDIST''' and '''INF_LAYERED_SOIL''' there will be two columns for each location.  If there is only one soil layer in your model, then the second column for each location will have a no data card, -999.99.  If you are simulating groundwater and the groundwater overtakes a layer at a location, you will get a no data card (-999.999) while that layer at that location is under the groundwater.  If you are not doing long term simulations, only the surface soil moisture is listed, so only one column per location.  If simulating '''INF_RICHARDS''' then there is output for every RE cell in the soil column for each output location.  As the number of cells in the RE solution can vary both spatially and temporally (when simulating groundwater), the number of output columns can vary over time.  For this reason, results from RE may be most useable if output only one location at a time.   
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Revision as of 20:56, 13 July 2018

Infiltration may be calculated using four different infiltration options. Green and Ampt (GA) (Green and Ampt, 1911), a multi-layered Green and Ampt Model, Green and Ampt with Redistribution (GAR) (Ogden and Saghafian, 1995), and Richards’ equation (RE) (Richards, 1931). Only one of these four methods should be selected.

Card Argument Description 
GREEN_AMPT
 none Specifies Green and Ampt (GA) infiltration calculations. 
INF_REDIST
 none Specifies Green and Ampt with Redistribution (GAR) infiltration calculations. 
INF_LAYERED_SOIL
 none Specifies three layered Green and Ampt infiltration. 
INF_RICHARDS
 none Specifies Richards’ Equation be used for infiltration.


3.6.1 Green and Ampt (GA)

When GREEN_AMPT is selected, values of hydraulic conductivity, wetting front suction head, porosity, and initial moisture are required. Parameter values may be input using the Mapping Table file or with the series of GRASS ASCII maps using the cards below.

Card Argument Description 
CONDUCTIVITY  "filename.ext"
 map name Name of GRASS ASCII map containing spatially varied values of soil saturated hydraulic conductivity (cm hr-1). REQUIRED for GREEN_AMPT or INF_REDIST. Mutually exclusive with Mapping Table file assignment. 
CAPILLARY  "filename.ext"
 map name Name of GRASS ASCII map containing spatially varied values of Green & Ampt wetting front capillary head parameter (cm). REQUIRED for GREEN_AMPT or INF_REDIST. Mutually exclusive with Mapping Table file assignment. 
POROSITY  "filename.ext"
 map name Name of GRASS ASCII map containing spatially varied values of soil porosity. REQUIRED for GREEN_AMPT or INF_REDIST. Mutually exclusive with Mapping Table file assignment. 
MOISTURE  [value]
 map name
or
none 		Used to assign the initial soil moisture content. If followed by a filename, the file will be read in as a GRASS ASCII initial soil volumetric water content map. If no input is specified, then the initial soil volumetric water content s will be input using the Mapping Table file. REQUIRED for GREEN_AMP or INF_REDIST.


3.6.2 Green and Ampt with Redistribution (GAR)

When GAR is specified, the GA parameters plus two additional parameters must be provided: the pore-distribution index, and residual saturation. These may be input in the Mapping Table file or by providing two GRASS ASCII maps using the cards below.

Card Argument Description 
PORE_INDEX  "filename.ext"
 map name Name of GRASS ASCII map containing spatially varied values of the Brooks & Corey (1964) pore-distribution index. REQUIRED for INF_REDIST. Mutually exclusive with Mapping Table file assignment. 
RESIDUAL_SAT  "filename.ext"
 map name Name of GRASS ASCII map containing spatially varied values of the volumetric water content of the soil at residual saturation. REQUIRED for INF_REDIST. Mutually exclusive with Mapping Table file assignment. 
FIELD_CAPACITY  "filename.ext"
 map name Name of GRASS ASCII map containing spatially varied values of the volumetric water content of the soil when gravity drainage ceases. REQUIRED for INF_REDIST. Mutually exclusive with Mapping Table file assignment.


3.6.3 Multi-layered Green and Ampt

The multi-layered GA parameters are assigned with the table described in Section 11, and referenced to an index map. The required project cards are listed below.

Card Argument Description 
SOIL_TYPE_MAP "filename.ext"
 index map file name Name of GRASS ASCII map containing index numbers related to soil type. 
SOIL_LAYER_INPUT_FILE  "filename.ext"
 file name Input ASCII file containing values GA parameter in three soil layers for each soil referenced to in the SOIL_TYPE_MAP.


3.6.4 Richards’ Equation

When INF_RICHARDS is selected additional cards are required. There are also a number of optional input and output cards, as described below. Richard' Equation parameters may be specified in the MAPPING_TABLE, as well as in separate ASCII files.

3.6.4.1 Required Inputs

Card Argument Description 
INF_RICHARDS
 none Specify Richards’ equation for calculation of soil moisture, infiltration, and ET if doing LONG_TERM simulations. 
RICHARDS_C_OPTION  [value]
 character string Type of water-content/head curve and hydraulic conductivity/head curve.
BROOKS - Brooks and Corey (1964), as extended by Hutson and Cass (1987), into the wet profile; or,
HAVERCAMP – Havercamp (1977) as modified by Lappala (1985).


3.6.4.2 Parameter Assignment - Required

Select either SOIL_TYPE_MAP and SOIL_LAYER_INPUT_FILE or use the Mapping Table.

Card Argument Description 
SOIL_LAYER_INPUT_FILE "filename.ext"
 file name Input ASCII file with soil layer input parameters. Not used with MAPPING_TABLE 
SOIL_TYPE_MAP  "filename.ext"
 index map file name Name of GRASS ASCII map of soil type integer values corresponding to SOIL_LAYER_INPUT_FILE. Not used with MAPPING_TABLE

3.6.4.3 Optional Inputs

Card Argument Default Description 
WATER_TABLE  "filename.ext"
 map name no water table Simulate effect of water table on soil moisture. Specify filename of GRASS ASCII map that contains starting elevations of water table (m). 
AQUIFER_DELTA_Z  ##.##
 real none Size of unsaturated cell to use in all cells below the soil column specified in the SOIL_LAYER_INPUT_FILE or Mapping Table (m). 
SEASONAL_RS
 none no seasonal canopy resistance (when card is absent) Vary the vegetation canopy resistance during the year. 
RICHARDS_UPPER_OPTION  [value]
 character
string 		NORMAL Method used to calculate hydraulic conductivity at ground surface under ponded conditions:

NORMAL – from cell-centered water content of first cell,
GREEN_AMPT - saturated hydraulic conductivity (Ks) of cell 1
AVERAGE - average of Ks and NORMAL 

GW_ASSIGN_THETA
 none do not assign
initial theta
assume
equilibrium
values 		Assign soil moisture from the file specified in the SOIL_LAYER_INPUT_FILE card, if simulating the water table. 
RICHARDS_ITER_MAX  ##
 integer 1 Maximum number of iterations on non-linear coefficients. 
RICHARDS_WEIGHT  ##.##
 real 1.0 Weight on inter-cell hydraulic conductivities:
1.0 - forward
0.5 - centered
0.0 - backwards
RICHARDS_K_OPTION  [value]
 character string ARITHMETIC Averaging method for inter-cell hydraulic conductivities,

GEOMETRIC or ARITHMETIC 

RICHARDS_DTHETA_MAX  ##.##
 real 0.025 Maximum allowable water content change during a time-step.

3.6.4.4 Optional Output

Card Argument Description 
IN_THETA_LOCATION  "filename.ext"
 file name Input ASCII file that contains locations (row col) of cells to output time series moisture data. Works with all infiltration types GREEN_AMPT INF_REDIST INF_LAYERED_SOIL INF_RICHARDS. Output is time series of soil moisture for each location. If doing LONG_TERM simulations, output is time series of soil moisture for each soil layer in your soil moisture model. The number of layers is dependent on how you have set up your soils. Output will be listed in the same order as the inputs. There will be one column for each soil layer for each output location. For INF_REDIST and INF_LAYERED_SOIL there will be two columns for each location. If there is only one soil layer in your model, then the second column for each location will have a no data card, -999.99. If you are simulating groundwater and the groundwater overtakes a layer at a location, you will get a no data card (-999.999) while that layer at that location is under the groundwater. If you are not doing long term simulations, only the surface soil moisture is listed, so only one column per location. If simulating INF_RICHARDS then there is output for every RE cell in the soil column for each output location. As the number of cells in the RE solution can vary both spatially and temporally (when simulating groundwater), the number of output columns can vary over time. For this reason, results from RE may be most useable if output only one location at a time. 
OUT_THETA_LOCATION  "filename.ext"
 file name Filename to output time series moisture data every HYD_FREQ time steps at cells specified in IN_THETA_LOCATION. Output is listed in same order as input. Output is time series of soil moisture for each location. If doing LONG_TERM simulations, output is time series of soil moisture for each soil layer in your soil moisture model. The number of layers is dependent on how you have set up your soils. Output will be listed in the same order as the inputs. There will be one column for each soil layer for each output location. For INF_REDIST and INF_LAYERED_SOIL there will be two columns for each location. If there is only one soil layer in your model, then the second column for each location will have a no data card, -999.99. If you are simulating groundwater and the groundwater overtakes a layer at a location, you will get a no data card (-999.999) while that layer at that location is under the groundwater. If you are not doing long term simulations, only the surface soil moisture is listed, so only one column per location. If simulating INF_RICHARDS then there is output for every RE cell in the soil column for each output location. As the number of cells in the RE solution can vary both spatially and temporally (when simulating groundwater), the number of output columns can vary over time. For this reason, results from RE may be most useable if output only one location at a time.

3.6.7 Special Infiltration Cards

Card Argument Description 
READ_SM_HOTSTART  "filename.ext"
 file name Input GRASS ASCII map file that contains starting surface soil moistures specified for every grid cell in the watershed. Works with all infiltration options. 
WRITE_SM_HOTSTART  "filename.ext"
 file name Filename to output GRASS ASCII map of soil moistures for every grid cell in the watershed at the end of the simulation. Works with all infiltration options.


GSSHA User's Manual

3 Project File
3.1     Required Inputs
3.2     Mapping Table – Optional
3.3     Overland Flow – Required
3.4     Interception – Optional
3.5     Rainfall Input and Options – Required
3.6     Infiltration – Optional
3.7     Channel Routing – Optional
3.8     Continuous Simulations – Optional
3.9     Saturated Groundwater Flow – Optional
3.10     Soil Erosion – Optional
3.11     Constituent Transport – Optional
3.12     Subsurface Drainage Network – Optional
3.13     Output Files – Required


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