Tracking Creatures of Bavarian Folklore Using a Least-Cost Path Model

Table of Contents

  1. Tracking Creatures of Bavarian Folklore Using a Least-Cost Path Model
  2. Setting up Your Workspace
  3. Preparing the Data
  4. Skill Drill: Geocoding an Address and Creating a CSV Table to Import As XY Data
  5. Skill Drill: Defining the Study Area
  6. Skill Drill: Acquire Elevation Data from the USGS National Map Viewer
  7. Skill Drill: Acquire Land Cover Data from the USGS National Map Viewer
  8. Skill Drill: Acquire Hydrography Data from the USGS National Map Viewer
  9. Changing Global Environment Settings for Raster Processing
  10. Creating Cost Surface Models Using a Relative Cost Scale
  11. Creating a Remap Table to Reclassify Elevation
  12. Skill Drill: Creating a Remap Table to Reclassify Slope
  13. Skill Drill: Creating a Remap Table to Reclassify Tree Canopy Density
  14. Converting the Hydrography Features to Cost Surface Models
  15. Creating a Total Cost Surface Model
  16. Creating a Cost-Distance Surface Model
  17. Creating a Migration Corridor
  18. Determining the Least-Cost Path
  19. Skill Drill: Creating a Map of the Results

Skill Drill: Acquire Land Cover Data from the USGS National Map Viewer

To complete the least-cost path analysis, you will also need a land cover layer with tree canopy density. Return to the USGS National Map Viewer. Use the same methods in the previous skill drill to locate the National Land Cover Database under the Datasets tab. Check the box next to National Land Cover Database. Under Product Search Filter, select the National Land Cover Database for 2011. Under Data Extent, select State. Then click Find Products.

An image of the National Map View data selection page.
To acquire this data, be sure the map extent on the right remains the same as in the previous step.

On the Products tab, you will see a list of datasets available for download. Find the NLCD 2011 Percent Tree Canopy, by State. Verify that the state name is Calfornia and then click on the download link. Save the file in your original folder and decompress it.

An image of the National Map Viewer products page.
In this image, the dataset you want is the first result. However, over time, the website may change. Be sure to read the title of the dataset before downloading.

In ArcMap, add NLCD 2011 Canopy Density Geo TIFF file to the map. The file name might vary, but at this time it is called NCLD2011_CAN_California.tif. This layer represents tree canopy density as a percentage with values ranging from 0% to 100%. To understand more about how this data was derived, you can read the metadata using the link provided by the USGS National Map Viewer. Use the Project Raster tool to create a copy of the data with the NAD 83 UTM Zone 10N spatial reference. Save the Output Raster Dataset to your working folder. Under Output Coordinate System, choose NAD_1983_UTM_Zone_10N. When you are ready, click OK.

Because this is a large dataset, it may take a while to project. You should expect to wait approximately 5 minutes depending on the speed of your computer.

An image of the Tree Canopy Density layer added to ArcMap
By default, the Tree Canopy Density layer is colored different shades of green. Black represents areas with no tree canopy cover. These areas include lakes and rivers as well as areas of high elevation.

Following the same steps used in the previous skill drill, clip the projected tree canopy raster dataset using the Clip tool located in the Raster Processing toolbox. You may use the 10-mile buffer as your output extent by browsing to the file.

An image of the tree canopy layer clipped.
Though the cell size of this data is different, the extent should match the clipped digital elevation model.