site scenario tool

No modifications are currently pending.

This tool replaces the Elevation Scenario tool in BAGIS V2. It improves the analysis on site representation by adding a buffer distance parameter for the sites. Three parameters can be applied to the sites to define "represented/non-represented" areas in the AOI. The parameters are:

• Buffer Distance of Sites: indicating the planar distance beyond which the site is not reliable for supporting forecast models. Deselect the check box to ignore the buffer distance of the site so that only elevation ranges are used to define the represented areas.

• Elevation Upper Range of Sites: indicating the additional elevation range above which the site is not reliable for supporting forecast models. Deselect the check box to include all the areas higher than the elevation of the site.

• Elevation Lower Range of Sites: Indicating the additional elevation range below which the site is not reliable for supporting forecast models. Deselect the check box to include all the areas lower than the elevation of the site.

The images of the new and old GUI are attached below.

New GUI

Original GUI

Functions:

1. There are 3 types of sites: 1. SNOTEL, 2. Snow Course (SCourse), and 3. Pseudo. Pseudo sites are created by the user using the Newsite control (Green + button) on the form. The Pseudo sites can be removed by the Deletesite (Red X) button. The data sources of the sites are stored in the AOI's layers.gdb. The feature classes for these sites are: snotel_sites, snowcourse_sites, and pseudo_sites. An AOI may have zero or more of these site files.

2. When the DockableWindow is loaded, the tool sets the form with the DEM stats, elevation unit, and a list of snotel/snow course/pseudo sites. The Name and Elevation values are from BA_SNAME and BA_SELEV (The "internal" unit is always in metric unit, i.e., meters. It's not related to how the user selects the unit option on the GUI. A unit conversion is required if the source unit is in feet.) fields in the layers' attribute table. The "existing sites" list is for displaying all SNOTEL, snow course, and pseudo sites from their feature classes. Please note that some of these sites in the featureclasses might be outside the AOI and within the "buffered AOI." Some analyses might involve using sites outside the AOIs. Sites will be listed in this order: SNOTEL, snow course, and pseudo in the order they occur in the source feature class. The datagridview allows users to sort the sites by clicking on the column heading manually if desired. By default, only SNOTEL and snow course sites are selected for analysis. When the window opens for the first time (i.e., when a new AOI is selected) and there is a previous analysis, then the parameters are set to those used in the previous analysis. If there is no previous run, then the default values are used.

3. The Elevation option buttons control the display unit of elevation values. The BufferDistance combox value controls the input unit of the buffer distance (no need to update the distance value when a new buffer distance unit is selected). All internal analyses are performed using the units that match the source data (i.e., DEM Z unit and DEM xy unit).

4. Users can use the 4 yellow-arrow buttons to add / remove the individual sites or all sites in the Scenario 1 sites list to / from the Scenario 2 sites list. Any unique site can be added to the Scenario 2 list only once (i.e., make sure that there is no duplicate entry in the Scenario 2 list). All values listed in both lists are read only. The Reload button loads the parameters, settings, and lists of sites from the last run.

5. The first column in the Scenario 1 sites lists is a check-box column indicating if a site is selected for analysis. Users can select a subset of the Scenario 1 sites to perform the analysis that represents, say, the "actual" site representation. The selection can be performed by clicking on the individual check boxes left to the sites or use the "Toggle Selection" button to reverses the selection status of the sites. Users can perform a "pseudo" representation analysis by compiling a list of sites on the Scenario 2 list. All sites listed on the Scenario 2 sites list are used in the analysis.

6. The pseudo site add/remove actions only add/remove sites to the Scenario 1 site list, but not the Scenario 2 sites list. The NewSite control allows a user to add a new pseudo site by clicking on the map. When first clicked, the AOI's hillshade layer and all existing sites layers are added to the map automatically for visual references. The tool then prompts for the user to enter the site name. The elevation value is acquired from the DEM; the upper and lower range values are set based on the upper and lower range parameters. Once the user confirms the location, a new point feature is added to the pseudo_sites featureclass. Users need to use ArcGIS' internal function to modify the site values (e.g., site name) if an update is required. The Deletesite button deletes the selected pseudo sites from the featureclass. SNOTEL and Snow Course sites can also be deleted with the Deletesite button. Please note that the deletion is permanent and cannot be undone. When a pseudo site is added, it appears only in the Scenario 1 sites list. The user needs to add the pseudo site to the Scenario 2 list if desired.

7. The Preview Sites button creates two maps showing the buffered selected existing sites and all Scenario 2 sites. The buffers can be graphics created in the graphiccontainer of the map document and are displayed with proper symbology.

8. The Calculate button performs the analysis by identifying the areas that fall within the buffer distance and the upper and lower ranges. There are two analyses performed when the Calculate button is clicked. One set of results represents the Scenario 1sites representation (performed only the selected SNOTEL, Snow Course, and Pseudo sites listed in the Scenario 1 sites list). The other set of results represents the Scenario 2 representation and is performed on all the sites listed in the Scenario 2 list. The output rasters are used for the scenario mapping functions that are already available in BAGIS. The output table is saved in HTML format and contains the information listed below. The Report Title specified on the dialog window is used as the main heading and page title of the HTML file. The report HTML file has a predefined internal name (scenario_report.html) but users can save it to a new file with a different name. The internal name is required to maintain the associations between the report and the maps. There are two categories in the output represented/non-represented rasters: 1. Represented and 2. Non-represented.

9. The representation maps for individual sites were created during the analysis and are available for viewing using the "Site Representations" tool (see the Site Representations section below).

10. If a previous analysis has been performed the Report button will be enabled. The report (an HTML file) is available for viewing by clicking on the "Report" button. Users can save the report to another file using the browser's save function if multiple scenarios are to be analyzed.

Analysis Output:

1. Time and date the report was generated

2. Report name - based on the fillable Report Title field

3. AOI name and folder path

4. AOI area in Square Miles, Acres, Square KM, and Hectares

5. AOI DEM min, max

6. Default values and units (use the following texts if a parameter is disabled in the analysis)

   • For buffer distance, "There was no distance limit on site representation"

   • For Upper range, "All areas above the site were represented"

   • For Lower range, "All areas below the site were represented"

7. A list (or table) of all selected SNOTEL, Snow Course, and pseudo sites in the Scenario 1 sites list (including type, name, elevation, upper range, lower range values)

8. Scenario 1 non-represented and represented areas in square miles, acres, square KM, hectares, and % of AOI area

9. A list (or table) of all selected sites, including SNOTEL, Snow Course, and Pseudo sites listed in the Scenario 2 sites list (type, name, elevation, upper range, lower range)

10. Scenario 2 non-represented and represented areas in square miles, acres, square KM, hectares, and % of AOI area

11. Tables of the difference between scenarios 1 and 2. One table shows the difference (i.e., Scenario 1 - Scenario 2 area values), the other table shows the areas of the four difference map categories. Both tables display the areas using the same units used in other tables.

Algorithms for performing site representation analysis:

Perform the analysis on both the Scenario 1 sites list and the Scenario 2 sites list separately.

1. Circular buffers are created for selected sites in SNOTEL, snow course, and pseudo layers. These buffer layers are saved for future reference. File name: Name + OID + _Buff

2. Retrieve individual geometry of the buffer and use it as a spatial filter, in conjunction with the attribute filter associated with elevation ranges, to perform a raster query on the AOI's DEM.

3. Save the query result as a raster dataset in analysis.gdb. A unique name is assigned as the raster name.

4. "Combine" the individual rasters to form a map (i.e., raster) showing "represented" and "non-prepresented" categories.

5. "Combine" the result of step #4 with the buffer to form a map showing "represented" and "non-represented".

When the buffer distance parameter is disabled, the analyses are performed on elevation range values only. The steps are:

1. Get the represented elevation range intervals and find the "union" of these intervals.

2. Reclassify the DEM using the represented intervals into represented and non-represented.

3. There will be no individual site analysis (maps) if buffer distance is disabled.

Mapping menu items

There are two new menu items added to the "Generate Maps" menu (see the graphics below)

Scenario 1 Representation

Displays a map showing the actual representation defined by the selected sites in the existing sites list with the defined parameters. The map shows three classes: represented and non-represented.

Scenario 2 Representation

Displays a map showing the pseudo representation defined by the selected sites in the scenario sites list with the defined parameters. The map shows two classes: represented and non-represented.

Difference of Representations

Displays a map showing the difference between the Scenarios 1 and 2 representations. There are four difference classes:

* Represented in both scenarios

* Not represented in both scenarios

* Represented only in Scenario 1

* Represented only in Scenario 2

Site Representations

Shows a window form that allows users display individual site's represented/non-represented areas without taking into account the representation of other sites. There are three representation categories: a) Non-represented above, b) Represented, c) Non-represented below.

1. List all types of sites when the form is first loaded. The check boxes left to the entries are checked for those sites that were used in the last analysis either as existing sites or as scenario sites.

2. Click on individual sites to display their representation maps. If the "Auto Zoom/Pan" option is enabled, then the map view is re-centered and zoomed to the selected site. If the "Clear maps of the other sites" option is enabled, then the map only shows the selected site. The maps for the other sites are removed from the TOC.

3. These maps show three classes: represented, non-represented above, non-represented below.

4. Users can use the information on the dialog window to find the names and location of the individual rasters for their own purposes.