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7.4 GIS Data

7.4.1 Sources of Geographic Data

LANDFIRE Data Distribution Site: Raster Data for vegetation, fuels, & terrain (http://landfire.cr.usgs.gov/viewer/)

United States Geological Survey Rapid Data Delivery System (RDDS) (http://rmgsc.cr.usgs.gov/rdds/index.shtml )

This is a very functional, efficient, and reliable system from which to obtain geospatial information. A user can zoom to an area of interest or select Quick Find to view a fire location, define an area for data extraction, select products, specify a projection, and download the data. Products include vector and raster data, such as active and previous fires, moderate resolution imaging spectroradiometer (MODIS), Remote Automated Weather Stations (RAWS), roads, rivers, lakes, ownership, orthoimagery, digital raster graphics (DRG), and digital elevation models (DEM). UserID/Password

USFS ArcGIS Image Server (http://fsweb.rsac.fs.fed.us/index.php?option=com_content&view=article&id=89&Itemid=245 )

USFS Geodata Clearinghouse (http://data.fs.usda.gov/geodata/)

National Park Service (NPS) Data and Information (http://www.nps.gov/gis/data_info )

RSAC – USGS Monitoring Trends in Burn Severity (MTBS) Website (http://www.mtbs.gov )

National Weather Data in shapefile Format: http://www.srh.noaa.gov/gis/kml/shapepage.htm


7.4.2 Map Datum

Some common datums, or GCSs, used in North America follow:


North American Datum of 1927 (NAD27)

Local datum well suited to the United States, Canada, Mexico, and the Carribean. Uses the Clarke 1866 spheroid.

North American Datum of 1983 (NAD83)

An earth-centered datum that corrects NAD27 coordinates based on both earth and satellite measurements. Uses the GRS 1980 spheroid. Coordinates are very similar to WGS84 coordinates and can be used interchangeably with them.

World Geodetic System of 1984 (WGS84)

Earth-centered datum common for datasets with a global extent. Uses the WGS 1984 spheroid. This is the datum that GPS coordinates are based on.

Geographic transformations



 A screenshot of the ArcGIS Geographic Coordinate System Warning screen that occurs when attempting to add a shapefile to a map that has a different datum, as described in the text adjacent to this image

ArcGIS gives us a warning if we attempt to add data to our map that have a different GCS, or datum. For example if we have one layer depicting the 40 fire behavior fuel models. As with projection on-the-fly, the data frame’s GCS defaults to that of the first layer added to the map, which is North American 1983,. If we then try to add a fire perimeter shapefile with the WGS 1984 geographic coordinate system, we get a warning that a geographic transformation may be necessary. A geographic transformation, sometimes referred to as a datum transformation, is a set of mathematical formulas for converting coordinates from one datum to another. At this point, you may specify the transformation by clicking the transformations box in the warning dialog box





7.4.3 Map Projections & Coordinate Systems
A map depicting a simplified view of the Universal Transverse Mercator (UTM) zones covering the conterminous United States, as described in the text above this image

A projected coordinate system can reference the same geographic locations using a Cartesian system, which includes a uniform, linear unit of measure.

Universal Transverse Mercator (UTM)

The UTM system divides the earth into 60 zones, each six degrees of latitude wide. Figure below depicts a simplified view of the UTM zones covering the conterminous United States.

State Plane Coordinate Systems

A good example of a PCS being independent of a particular map projection. Lambert Conformal Conic projections are used for greatest in east-west extent, Transverse Mercator projections are used for greatest in north-south extent, & the some use an oblique Mercator projection.


7.4.4 Reprojecting shapefile or arcgrid in ArcGIS
An Arc Map screenshot that shows a FARSITE model reference for a landscape editor’s re-projection of an existing shapefile,  as described in the text adjacent to this image

If a shapefile or ascii grid will not display as an overlay on a landscape (lcp) in FARSITE, FLAMMAP, it cannot be used or displayed by those systems. It is most likely using a different coordinate system than the lcp does.

In this case, the file (feature/shapefile or raster/ascii grid) can be re-projected to the same coordinate system so it can be displayed onscreen and used in reference by the landscape editor in FARSITE.

  1. Open up a new ArcMap window and add the shapefile or raster file that is stored in the desired projection. By adding the shapefile (or grid) with the desired projection first, the coordinate system of the Data Frame will default to the desired projection.
  2. Next, add the shapefile that is stored in the other projection.
  3. If the ArcToolbox window is not already displayed, click on the ArcToolbox icon to show the ArcToolbox window.
  4. In the ArcToolbox window, click on the plus sign next to “Data Management Tools” to expand the selection. Next, click on the plus sign next to “Projections and Transformations” to expand the selection. Next, click on the plus sign next to “Feature” (for shapefiles or “Raster” (for grids) to expand the selection. Double-click on “Project” to open up the tool.
  5. In the Project window, under “Input Dataset or Feature Class,” select the shapefile/raster grid that is currently stored in the wrong projection. The Input Coordinate System should automatically default to its projection.” If none is displayed, that means that there is no prj file accompanying it. If known, it can be specified here.
  6. Specify an output shapefile or raster grid under “Output Dataset or Feature Class.” Click on the button next to “Output Coordinate System.” In the “Spatial Reference Properties” window that pops up, click on the “Import” button. Navigate to and select the shapefile that is stored in desired coordinate system. The new projection properties will load into the “Spatial Reference Properties” window. Click “OK” on the “Spatial Reference Properties” window.
    An Arc Map screenshot that shows a FARSITE model reference for a landscape editor’s re-projection of an existing shapefile,  as described in the text adjacent to this image
Click “OK” in the “Project” window to create a new shapefile that is stored in the chosen UTM projection.

If during the re-projection process, the user discovers that the feature or raster does not have a defined projection; one can be added by selecting “Define Projection”, also found under “Projections and Transformations”.

7.4.5 Convert a shapefile to an ASCII raster file

Understanding Raster Data; http://www.fire.org/niftt/released/RasterPrimer.pdf

While shapefiles can be displayed in both FLAMMAP and FARSITE, they cannot be used to make edits to an LCP using the FARSITE Landscape Calculator. In order to be used by the Calculator, a shapefile must be converted to an ASCII Raster. This is a two-step process and can be done in ArcGIS using the ArcToolbox. The first step is to convert the shapefile to a Raster GRID. The final step is to export the Raster GRID as an ASCII Raster.

Part A: Converting a shapefile to a Raster GRID file
An ArcMap, Arc Toolbox screenshot that shows steps for converting an existing shapefile to a Raster GRID (part A) as described in the text adjacent to this image
An ArcMap, Arc Toolbox screenshot that shows steps for converting the Raster GRID to an ASCII Raster (part B) to allow edits using a FARSITE calculator, as described in the text adjacent to this image













  1. Within ArcMap or ArcCatalog, click on the ArcToolbox icon .
  2. In ArcToolbox, click on the plus sign next to “Conversion Tools” to expand the selection. Next, click on the plus sign next to “To Raster” to expand the selection. Double-click on “Feature to Raster” to open up the tool.
  3. In the “Feature to Raster” tool window, below “Input Features,” select or navigate to the shapefile that you want to convert. Under “Field” select a non-numeric attribute field.
  4. Below “Output Raster,” specify the name and location of the output raster GRID file. Keep in mind that the names of raster GRID files have a maximum length of 13 characters.
  5. Under “Output cell size,” specify an output cell size of 30 meters so that the output grid resolution is consistent with the resolution of the FARSITE LCP. Click “OK” to create the raster GRID file.










Part B: Converting a Raster GRID to an ASCII Raster file
An Arc Map, Arc Toolbox  screenshot that shows  a FARSITE model reference for landscape editor steps for converting an existing shapefile to a Raster GRID shapefile (Part A), and then converting the Raster GRID to an ASCII  Raster shapefile (Part B) to allow edits using a FARSITE calculator, as described in the text adjacent to this image
An Arc Map, Arc Toolbox  screenshot that shows  a FARSITE model reference for landscape editor steps for converting an existing shapefile to a Raster GRID shapefile (Part A), and then converting the Raster GRID to an ASCII  Raster shapefile (Part B) to allow edits using a FARSITE calculator, as described in the text adjacent to this image



1. In ArcToolbox, click on the plus sign next to “Conversion Tools” to expand the selection. Next, click on the plus sign next to “From Raster” to expand the selection. Double-click on “Raster to ASCII” to open up the tool.

2. Below “Input raster,” select the raster GRID file you created in Part A. Under “Output ASCII raster file,” specify an output name and location. Be sure to specify the file type as .ASC. Click “OK” to create the ASCII Raster file.


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