WMS:GSSHA Feature Arcs: Difference between revisions

From XMS Wiki
Jump to navigationJump to search
(rm related in template)
No edit summary
Line 1: Line 1:
{{TOCright}}
{{TOCright}}
The ''Coverage Properties'' dialog is where the attributes associated with feature arcs on the GSSHA coverage are defined. This dialog is accessed either by double-clicking on a feature arc or by selecting the ''Feature Objects'' | '''Attributes...''' menu command in the Map module. It is possible to change the feature type attributes that are displayed in the table, select whether to show attributes for all features or just the selected features, and to filter the data shown in the table based on specific attribute values.
Feature arcs in GSSHA have several attributes that can be modified, depending on the type of feature arc. There are five types of feature arcs in GSSHA:
[[Image:GsshaArcAtts.jpg|thumb|none|left|800 px|The ''Coverage Properties'' dialog is where the attributes are associated with feature arcs.]]
* Generic
==GSSHA Arc Types==
* General stream
===Generic ===
* Trapezoidal channel
Generic arcs have no attributes and are typically used when constructing polygons.
* Cross section channel
* Embankment


*''Parameters'': None.
The ''Properties'' Dialog allows modification of the various attributes of feature arcs.


===General Stream===  
==''Properties'' Dialog==
General stream arcs are identical to streams defined for drainage coverages and are used when going back and forth between coverage types. General stream arcs are not used to generate input for GSSHA simulations.
{{Wide image|GsshaArcAtts.jpg|2400px|The ''Coverage Properties'' dialog is where the attributes are associated with feature arcs. Scroll to the right to see the full dialog.|800|none|alt=The ''Coverage Properties'' dialog is where the attributes are associated with feature arcs.|}}
The ''Properties'' dialog for feature arcs in GSSHA lists the various attributes associated with each feature arc. This dialog is accessed either by double-clicking on a feature arc or by selecting the ''Feature Objects'' | '''Attributes...''' menu command while in the '''Map''' module. Most of the attributes can be changed in this dialog, or by clicking a button in this dialog to open a separate dialog. The options for feature points and nodes are described in the [[WMS:GSSHA Feature Nodes|GSSHA Feature Nodes]] article.


*''Parameters'': None.
===Dialog Display Options===
At the top of the dialog are two main drop-downs:
* ''Feature type''
** "Arcs" – Selecting this option displays only arcs in the spreadsheet section.
** "Points/nodes" – Selecting this option displays only points and/or nodes in the spreadsheet section.
* ''Show''
** "All" – Displays in the spreadsheet section all of the ''Feature type'' selected in the above drop-down.
** "Selected" – Displays in the spreadsheet section only the "Feature type'' that were selected in the Main Graphics Window.


===Trapezoidal Channel===
The two drop-downs listed under ''Filter using'' are:
Trapezoidal cross sections are used to define channel routing in GSSHA models. WMS automatically assigns a link number to trapezoidal channel arcs. By default the geometric parameters of the trapezoidal channel are applied to the entire channel (link), although it is possible to assign both upstream and downstream geometric parameters for the channel (link) by toggling on the [2] Geometry option. GSSHA will interpolate a cross section at each node in the link using the upstream and downstream channel geometries.
* ''Column''
** "None" – Does not filter what is displayed in the spreadsheet section.
** "Type" – Uses the type shown in the ''Value'' drop-down to filter what is displayed in the spreadsheet section.
** "Groundwater BC" – Uses the groundwater BC type shown in the ''Value'' drop-down to filter what is displayed in the spreadsheet section.
* ''Value'' –
** If "Type" is selected in the ''Column'' drop-down, the following options display:
*** "Generic" – Shows only feature arcs with the type of "Generic" in the spreadsheet section.
*** "General stream" – Shows only feature arcs with the type of "General stream" in the spreadsheet section.
*** "Trapezoidal channel" – Shows only feature arcs with the type of "Trapezoidal channel" in the spreadsheet section.
*** "Cross section channel" – Shows only feature arcs with the type of "Cross section channel" in the spreadsheet section.
*** "Embankment" – Shows only feature arcs with the type of "Embankment" in the spreadsheet section.
** If "Groundwater BC" is selected in the ''Column'' drop-down, the following options display:
*** "Generic" – Shows only feature arcs with "Generic" selected from the drop-down in the ''Groundwater BC'' column in the spreadsheet section.
*** "No flow" – Shows only feature arcs with "No flow" selected from the drop-down in the ''Groundwater BC'' column in the spreadsheet section.
*** "Constant head" – Shows only feature arcs with "Constant head" selected from the drop-down in the ''Groundwater BC'' column in the spreadsheet section.
*** "Flux river" – Shows only feature arcs with "Flux river" selected from the drop-down in the ''Groundwater BC'' column in the spreadsheet section.
*** "Head river" – Shows only feature arcs with "Head river" selected from the drop-down in the ''Groundwater BC'' column in the spreadsheet section.


*''Parameters'': Manning’s n value, channel depth, bottom width, and side slope.
===Arcs Spreadsheet===
*''Other'': Enter the maximum depth of channel erosion if the soil erosion option is turned on in the ''Job Control'',
The columns in the spreadsheet section when "Arcs" is selected from the ''Feature type'' drop-down are described below. The options for feature points and nodes are described in the [[WMS:GSSHA Feature Nodes|GSSHA Feature Nodes]] article.


===Cross Section Channel===
Note that the columns are listed in order of appearance. Depending on which feature arc type is selected, not all may be visible.  
The profile of irregular cross sections are defined using X, Y coordinate pairs. GSSHA computes conveyance parameters including area, top width, and conveyance at incremental depths of flow up to the maximum depth specified in the Max conveyance depth column of the table.


*''Parameters'': Manning's n value, cross section profile, and maximum conveyance depth.
;ID
*''Other'': Enter the maximum depth of channel erosion if the soil erosion option is turned on in the ''Job Control''.
:Unique ID assigned to the arc. Not user editable.


===Embankment===
;Type
Embankments represent overland flow hydraulic structures such as levees or roads. They modify flow by either preventing flow between adjacent cells or acting as a weir if the flow reaches above the crest elevation of the embankment.
:A drop-down list of GSSHA feature arc types:
:* "Generic" – Generic feature arcs have no attributes and are typically used when constructing polygons.
:* "General stream" – General stream arcs are identical to streams defined for drainage coverages and are used when going back and forth between coverage types. General stream arcs are not used to generate input for GSSHA simulations.
:* "Trapezoidal channel" – Trapezoidal channels are used to define channel routing in GSSHA models. WMS automatically assigns a link number to trapezoidal channel arcs. By default, the geometric parameters of the trapezoidal channel are applied to the entire channel, although it is possible to assign both upstream and downstream geometric parameters for the channel by turning on ''[2] Geometry'' in the ''Properties'' dialog. GSSHA will interpolate a cross section at each node in the link using the upstream and downstream channel geometries.
:* "Cross section channel" – The profile of irregular cross sections are defined using ''XY'' coordinate pairs. GSSHA computes conveyance parameters including area, top width, and conveyance at incremental depths of flow up to the maximum depth specified in the Max conveyance depth column of the table.
:* "Embankment" – Embankments represent overland flow hydraulic structures such as levees or roads. They modify flow by either preventing flow between adjacent cells or acting as a weir if the flow reaches above the crest elevation of the embankment. See more at the [[WMS:GSSHA Embankment Arcs|GSSHA Embankment Arcs]] article.


*''Parameters'': embankment profile.
;Link
:The link number assigned to the arc. Only editable for feature arc types of "Trapezoidal channel" and "Cross section channel".


See [[WMS:GSSHA Embankment Arcs|GSSHA Embankment Arcs]] for more information.
;Manning's n
:A Manning's ''n'' roughness coefficient. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".


===Pipe===
;Depth
Pipe arcs are used to conceptualize sub-surface storm/tile drain systems. Looped configurations are allowed.
:The maximum depth of the channel represented by the GSSHA feature arc in meters. Only available for feature arc types of "Trapezoidal channel".


*''Parameters'': type (circular or rectangular), geometric properties, slope, Manning's n value, length, conductance (tile drains only), and superlink number.
;Bottom width
:The width of the bottom of the channel in meters. Only available for feature arc types of "Trapezoidal channel".


==Sub-surface Losses/Gains==
;Side slope (H:V)
If the ''Groundwater (sub-surface)'' option in the ''GSSHA Job Control'' is turned on then it is possible to toggle on the option to compute sub-surface losses/gains by entering sediment thickness and hydraulic conductvity.
:The horizontal value to one unit of vertical rise. Only available for feature arc types of "Trapezoidal channel".


==Groundwater BC==
;Max conveyance depth
Assign one of the following groundwater boundary conditions to the 2D grid cells intersecting the feature arc: Generic, No Flow, Constant Head, Flux River, or Head River. For more information, see [[WMS:GSSHA Groundwater|GSSHA Groundwater]].
:The maximum depth of the channel represented by the GSSHA feature arc in meters. Only applicable for feature arc types of "Cross section channel".


==Solution Results==
;Cross section
Click on the button to view results at all node locations for the link in the stream/channel network. See [[WMS:GSSHA Solution Results|GSSHA Solution Results]] for information.
:Clicking [[File:Dot dot dot button.png|16px]] brings up the [[WMS:XY Series Editor|''XY Series Editor'' dialog]] to allow editing of cross section values. Only available if the type is set to "Cross section channel".


==Specified Overbank and Backwater Channel Links==
;Define Interpolation Points
GSSHA has two options that could be defined globally. The first option, the overbank flow option (OVERBANK_FLOW), increases the level of connection between the overland flow and the channel in the 1D hydraulic model by allowing water to spill from the channel back onto the overland flow plane. If the second option, the overland backwater option (OVERLAND_BACKWATER), is turned on, flow from the overland flow model to the channel in the 1D hydraulic model is restricted if the elevation of the water in the channel exceeds the overland cell elevation. This option can  be defined at each of the arcs (links) in the GSSHA model in the GSSHA arc properties dialog. If this option is defined for one of the arcs, the global option is turned off.
:Turn on to define reveal ''Number of Interpolation Points" column. Only available for feature arc types of "Cross section channel".


:[[Image:GsshaOverbankBackwaterOptions.png|thumb|none|left|500 px|GSSHA arc overbank and overland backwater options]]
;Number of Interpolation Points
:An integer value. Only available for feature arc types of "Cross section channel".
 
;Overbank Flow
:Turn on to enable overbank flow (OVERBANK_FLOW). Increases the level of connection between the overland flow and the channel in the 1D hydraulic model by allowing water to spill from the channel back onto the overland flow plane. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
 
;Overland Backwater
:Turn on to enable overland backwater (OVERLAND_BACKWATER). Flow from the overland flow model to the channel in the 1D hydraulic model is restricted if the elevation of the water in the channel exceeds the overland cell elevation. This option can be defined at each of the arcs (links) in the GSSHA model. If this option is defined for one of the arcs, the global option is turned off. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
 
;[2] Geometry
:Turns on the option to specify downstream geometry, allowing GSSHA to interpolate between upstream and downstream. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
 
:;[2] Manning's n
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
 
:;[2] Depth
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Trapezoidal channel".
 
:;[2] Bottom width
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Trapezoidal channel".
 
:;[2] Side slope (H:V)
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Trapezoidal channel".
 
:;[2] Max conveyance depth
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Cross section channel".
 
:;[2] Cross section
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Cross section channel".
 
:;[2] Define Interpolation Points
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Cross section channel".
 
:;[2] Number of Interpolation Points
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Cross section channel".
 
:;[2] Overbank Flow
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
 
:;[2] Overland Backwater
::Available if ''[2] Geometry'' is turned on. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
 
;Max erosion
:The maximum depth of erosion. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
 
;Embankment
:Clicking [[File:Dot dot dot button.png|16px]] brings up the [[WMS:GSSHA Embankment Arcs#Embankment Arc Profile Editor Dialog|''Embankment Arc Profile Editor'' dialog]]. Only available for feature arc types of "Embankment".
 
;Sub-surface losses/gains
:If the ''Groundwater'' option in the [[WMS:GSSHA Job Control|''GSSHA Job Control'' dialog]] is turned on, this option can be turned on in order to compute sub-surface losses/gains by entering sediment thickness and hydraulic conductivity. Only available for feature arc types of "Trapezoidal channel".
 
:;Sediment thickness
::A decimal value in centimeters. Only available for feature arc types of "Trapezoidal channel".
 
:;Sediment hydraulic conductivity
::A decimal value in centimeters per hour. Only available for feature arc types of "Trapezoidal channel".
 
;Groundwater BC
:A drop-down list of groundwater boundary conditions to assign to the 2D grid cells intersecting the feature arc. For more information, see [[WMS:GSSHA Groundwater|GSSHA Groundwater]].
:*"Generic"
:*"No Flow"
:*"Constant Head"
:*"Flux River"
:*"Head River"
 
;Overland Flow BC Type
:A drop-down list of overland flow boundary condition types:
:*"None"
:*"Constant slope"
:*"Constant stage (water surface elevation)"
:*"Variable stage (water surface elevation)"
:*"Variable flow (cms discharge)"
:*"Variable flow (cfs discharge)"
:*"Head difference rating curve"
:*"Depth rating curve"
:*"Receiving cell"
 
;Variable BC
:Clicking [[File:Dot dot dot button.png|16px]] brings up the [[WMS:XY Series Editor|''XY Series Editor'' dialog]], allowing variable boundary condition data to be reviewed, edited, imported, or exported. Only available if "Variable stage (water surface elevation)", "Variable flow (cms discharge)", "Variable flow (cfs discharge)", "Head difference rating curve", or "Depth rating curve" are selected from the drop-down in the ''Overland Flow BC Type'' column.
 
;Constant BC
:A decimal value for a constant boundary condition. Only editable if "Constant slope" or "Constant stage (water surface elevation)" selected in the ''Overland Flow BC Type'' column.
 
;Solution Results
:Click [[File:Dot dot dot button.png|16px]] to view results at all node locations for the link in the stream/channel network. For more information, see [[WMS:GSSHA Solution Results|GSSHA Solution Results]]. Only available after a GSSHA simulation has been completed.





Revision as of 21:18, 18 April 2019


Feature arcs in GSSHA have several attributes that can be modified, depending on the type of feature arc. There are five types of feature arcs in GSSHA:

  • Generic
  • General stream
  • Trapezoidal channel
  • Cross section channel
  • Embankment

The Properties Dialog allows modification of the various attributes of feature arcs.

Properties Dialog

The Coverage Properties dialog is where the attributes are associated with feature arcs.
The Coverage Properties dialog is where the attributes are associated with feature arcs. Scroll to the right to see the full dialog.

The Properties dialog for feature arcs in GSSHA lists the various attributes associated with each feature arc. This dialog is accessed either by double-clicking on a feature arc or by selecting the Feature Objects | Attributes... menu command while in the Map module. Most of the attributes can be changed in this dialog, or by clicking a button in this dialog to open a separate dialog. The options for feature points and nodes are described in the GSSHA Feature Nodes article.

Dialog Display Options

At the top of the dialog are two main drop-downs:

  • Feature type
    • "Arcs" – Selecting this option displays only arcs in the spreadsheet section.
    • "Points/nodes" – Selecting this option displays only points and/or nodes in the spreadsheet section.
  • Show
    • "All" – Displays in the spreadsheet section all of the Feature type selected in the above drop-down.
    • "Selected" – Displays in the spreadsheet section only the "Feature type that were selected in the Main Graphics Window.

The two drop-downs listed under Filter using are:

  • Column
    • "None" – Does not filter what is displayed in the spreadsheet section.
    • "Type" – Uses the type shown in the Value drop-down to filter what is displayed in the spreadsheet section.
    • "Groundwater BC" – Uses the groundwater BC type shown in the Value drop-down to filter what is displayed in the spreadsheet section.
  • Value
    • If "Type" is selected in the Column drop-down, the following options display:
      • "Generic" – Shows only feature arcs with the type of "Generic" in the spreadsheet section.
      • "General stream" – Shows only feature arcs with the type of "General stream" in the spreadsheet section.
      • "Trapezoidal channel" – Shows only feature arcs with the type of "Trapezoidal channel" in the spreadsheet section.
      • "Cross section channel" – Shows only feature arcs with the type of "Cross section channel" in the spreadsheet section.
      • "Embankment" – Shows only feature arcs with the type of "Embankment" in the spreadsheet section.
    • If "Groundwater BC" is selected in the Column drop-down, the following options display:
      • "Generic" – Shows only feature arcs with "Generic" selected from the drop-down in the Groundwater BC column in the spreadsheet section.
      • "No flow" – Shows only feature arcs with "No flow" selected from the drop-down in the Groundwater BC column in the spreadsheet section.
      • "Constant head" – Shows only feature arcs with "Constant head" selected from the drop-down in the Groundwater BC column in the spreadsheet section.
      • "Flux river" – Shows only feature arcs with "Flux river" selected from the drop-down in the Groundwater BC column in the spreadsheet section.
      • "Head river" – Shows only feature arcs with "Head river" selected from the drop-down in the Groundwater BC column in the spreadsheet section.

Arcs Spreadsheet

The columns in the spreadsheet section when "Arcs" is selected from the Feature type drop-down are described below. The options for feature points and nodes are described in the GSSHA Feature Nodes article.

Note that the columns are listed in order of appearance. Depending on which feature arc type is selected, not all may be visible.

ID
Unique ID assigned to the arc. Not user editable.
Type
A drop-down list of GSSHA feature arc types:
  • "Generic" – Generic feature arcs have no attributes and are typically used when constructing polygons.
  • "General stream" – General stream arcs are identical to streams defined for drainage coverages and are used when going back and forth between coverage types. General stream arcs are not used to generate input for GSSHA simulations.
  • "Trapezoidal channel" – Trapezoidal channels are used to define channel routing in GSSHA models. WMS automatically assigns a link number to trapezoidal channel arcs. By default, the geometric parameters of the trapezoidal channel are applied to the entire channel, although it is possible to assign both upstream and downstream geometric parameters for the channel by turning on [2] Geometry in the Properties dialog. GSSHA will interpolate a cross section at each node in the link using the upstream and downstream channel geometries.
  • "Cross section channel" – The profile of irregular cross sections are defined using XY coordinate pairs. GSSHA computes conveyance parameters including area, top width, and conveyance at incremental depths of flow up to the maximum depth specified in the Max conveyance depth column of the table.
  • "Embankment" – Embankments represent overland flow hydraulic structures such as levees or roads. They modify flow by either preventing flow between adjacent cells or acting as a weir if the flow reaches above the crest elevation of the embankment. See more at the GSSHA Embankment Arcs article.
Link
The link number assigned to the arc. Only editable for feature arc types of "Trapezoidal channel" and "Cross section channel".
Manning's n
A Manning's n roughness coefficient. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
Depth
The maximum depth of the channel represented by the GSSHA feature arc in meters. Only available for feature arc types of "Trapezoidal channel".
Bottom width
The width of the bottom of the channel in meters. Only available for feature arc types of "Trapezoidal channel".
Side slope (H:V)
The horizontal value to one unit of vertical rise. Only available for feature arc types of "Trapezoidal channel".
Max conveyance depth
The maximum depth of the channel represented by the GSSHA feature arc in meters. Only applicable for feature arc types of "Cross section channel".
Cross section
Clicking Dot dot dot button.png brings up the XY Series Editor dialog to allow editing of cross section values. Only available if the type is set to "Cross section channel".
Define Interpolation Points
Turn on to define reveal Number of Interpolation Points" column. Only available for feature arc types of "Cross section channel".
Number of Interpolation Points
An integer value. Only available for feature arc types of "Cross section channel".
Overbank Flow
Turn on to enable overbank flow (OVERBANK_FLOW). Increases the level of connection between the overland flow and the channel in the 1D hydraulic model by allowing water to spill from the channel back onto the overland flow plane. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
Overland Backwater
Turn on to enable overland backwater (OVERLAND_BACKWATER). Flow from the overland flow model to the channel in the 1D hydraulic model is restricted if the elevation of the water in the channel exceeds the overland cell elevation. This option can be defined at each of the arcs (links) in the GSSHA model. If this option is defined for one of the arcs, the global option is turned off. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
[2] Geometry
Turns on the option to specify downstream geometry, allowing GSSHA to interpolate between upstream and downstream. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
[2] Manning's n
Available if [2] Geometry is turned on. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
[2] Depth
Available if [2] Geometry is turned on. Only available for feature arc types of "Trapezoidal channel".
[2] Bottom width
Available if [2] Geometry is turned on. Only available for feature arc types of "Trapezoidal channel".
[2] Side slope (H:V)
Available if [2] Geometry is turned on. Only available for feature arc types of "Trapezoidal channel".
[2] Max conveyance depth
Available if [2] Geometry is turned on. Only available for feature arc types of "Cross section channel".
[2] Cross section
Available if [2] Geometry is turned on. Only available for feature arc types of "Cross section channel".
[2] Define Interpolation Points
Available if [2] Geometry is turned on. Only available for feature arc types of "Cross section channel".
[2] Number of Interpolation Points
Available if [2] Geometry is turned on. Only available for feature arc types of "Cross section channel".
[2] Overbank Flow
Available if [2] Geometry is turned on. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
[2] Overland Backwater
Available if [2] Geometry is turned on. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
Max erosion
The maximum depth of erosion. Only available for feature arc types of "Trapezoidal channel" and "Cross section channel".
Embankment
Clicking Dot dot dot button.png brings up the Embankment Arc Profile Editor dialog. Only available for feature arc types of "Embankment".
Sub-surface losses/gains
If the Groundwater option in the GSSHA Job Control dialog is turned on, this option can be turned on in order to compute sub-surface losses/gains by entering sediment thickness and hydraulic conductivity. Only available for feature arc types of "Trapezoidal channel".
Sediment thickness
A decimal value in centimeters. Only available for feature arc types of "Trapezoidal channel".
Sediment hydraulic conductivity
A decimal value in centimeters per hour. Only available for feature arc types of "Trapezoidal channel".
Groundwater BC
A drop-down list of groundwater boundary conditions to assign to the 2D grid cells intersecting the feature arc. For more information, see GSSHA Groundwater.
  • "Generic"
  • "No Flow"
  • "Constant Head"
  • "Flux River"
  • "Head River"
Overland Flow BC Type
A drop-down list of overland flow boundary condition types:
  • "None"
  • "Constant slope"
  • "Constant stage (water surface elevation)"
  • "Variable stage (water surface elevation)"
  • "Variable flow (cms discharge)"
  • "Variable flow (cfs discharge)"
  • "Head difference rating curve"
  • "Depth rating curve"
  • "Receiving cell"
Variable BC
Clicking Dot dot dot button.png brings up the XY Series Editor dialog, allowing variable boundary condition data to be reviewed, edited, imported, or exported. Only available if "Variable stage (water surface elevation)", "Variable flow (cms discharge)", "Variable flow (cfs discharge)", "Head difference rating curve", or "Depth rating curve" are selected from the drop-down in the Overland Flow BC Type column.
Constant BC
A decimal value for a constant boundary condition. Only editable if "Constant slope" or "Constant stage (water surface elevation)" selected in the Overland Flow BC Type column.
Solution Results
Click Dot dot dot button.png to view results at all node locations for the link in the stream/channel network. For more information, see GSSHA Solution Results. Only available after a GSSHA simulation has been completed.