Setting Initial Conditions for Water Column Constituents

The following form is used to set the initial conditions for any water column parameter.  Depending on which parameter was selected elsewhere in EE, the form is displayed with the parameter being set shown in the title bar.

Figure 1.

Several options are available for IC settings.  Which option is used depends on the model needs and available data.

Step-by-step guide

Option 1: Use Constant 

This option sets a constant (or operator) value to the cells.  Each layer or all the layers can be set at once using the "Layer Options".  Operators (link to discussion of operators) can be used to adjust existing IC values.

1. Click on the "Use Constant" option
2. Select a Poly File to use if needed to apply only to a sub-domain. Make sure the field is empty if you want to apply the constant value (or operator) to the entire domain.
3. Select which layer to apply the constant to, or check the "Set for All the Layers" option to apply the constant to all the layers, i.e. depth averaged IC.
4. Click Apply.  EE will report the number of horizontal cells it changed/updated.
5. Repeat for each layer, if needed.
6. Repeat for different sub-domains, if needed.

Option 2: Use Point Measurements/Gridded Data

This option will use data contained in the VP/Data File field and apply an inverse distance weighted (IDW) interpolation approach to the cells.  The data format is an ASCII file containing XYZ data.  The horizontal coordinates must be in the same coordinate system as the model files.  The Z value will be interpolated onto the grid.  The IDW options can be changed from the defaults using the Options button.  Each layer or all the layers can be set at once using the "Layer Options".   Operators can still be used when using the IDW approach.

1. Click on the "Use Point Measurements/Gridded Data" option
2. Select the XYZ data file using the Browse button on the VP/Data File filed or just type in the full pathname.
3. Select a Poly File to use, if need to apply only to a sub-domain, or make sure the field is empty if you want to apply the XYZ data 
4. Set the "Operator" field to 0 or enter an operator.  0 will force EE to ignore the operator field while assigned the IC data.
5. Select which layer to apply the constant to or check the "Set for All the Layers" option to apply the constant to all the layers, i.e. depth averaged IC.
6. Click Apply.  EE will report the number of horizontal cells it changed/updated.
7. Repeat for each layer, if needed.
8. Repeat for different sub-domains, if needed.

Option 3: Assign Value Using Vertical Profiles

If this option is selected, the Layer Option feature is disabled since this option sets the IC for all layers.  This option requires an ASCII data file in the format shown in B-6.  When the Apply button is pressed, EE interpolates these data onto the water column initial conditions both horizontally and vertically (all active layers).  Any number of vertical profiles can be used.  If the layers are above or below the defined vertical profile, the layer assignments will be constant at the last valid elevation.

1. Click on the "Assign Value Using Vertical Profiles" option
2. Select the vertical profile data file using the Browse button on the VP/Data File filed or just type in the full pathname.
3. Select a Poly File to use, if need to apply only to a sub-domain, or make sure the field is empty if you want to apply the XYZ data 
4. Set the "Operator" field to 0 or enter an operator.  0 will force EE to ignore the operator field while assigned the IC data.
5. Click Apply.  EE will report the number of horizontal cells it changed/updated.
6. Repeat for different sub-domains, if needed.

Applying the IC Assigments to a Specific Region or Sub-Set of Cells

All three options listed above can be optionally applied to a user defined region.  By default, if the user does not provide a Poly File, the selected option will be assigned to the entire domain when the user clicks the Apply button.  The user may select one region using the Poly File, pick the assignment option and hit Apply, then select another region and repeat the process until the entire model domain has been assigned.  The user can overwrite any IC's already assigned for any sub-domain.  For example, the user can apply a constant for the entire domain, then use the Poly File to select a sub-domain to apply some special/different IC to that region.

Poly File: The Poly File field is an optional field used to specify a polygon/polyline file using any EE recognized polyline/polygon formats.  The file may contain contains more than one polygon/polyline.  Cells that are inside the polygon(s), using the Inside Cell Test options, will be adjusted according to the options specified in the Modify Options frame.  If the Poly File is missing, EFDC_Explorer will use all of the cells in the model

Inside Cell Test:  The Inside Cell Test options only are used if a Poly File has been provided.  The application of the Inside Cell Test determines how EE will treat model cells that are partially inside the polygon.  The user selects which method EE will use based on either the cell centroid (the default) to using the number of corners.  To be more inclusive, the user can select only 

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