PrintSiting projects use the full spectrum of GIS data, including vector date, raster data, attribute data, and imagery. As you learned in Lesson 3, vector data is represented by points, lines, or polygons, while raster data can consist of gridded data, such as topographical maps and digital elevation models, attribute data, which describes characteristics of the spatial features, and, finally, aerial and satellite imagery.
Where to find GIS information
There are many sources for obtaining data for siting projects. Many sources of data are available for download, and I would encourage you to explore on your own to find additional sources. A good summary of the topic of GIS data sources can be found at Maps & Geospatial: Geographic Information Systems (GIS) .
The USGS Center for Excellence for Geospatial Information Sciences is a good place to start finding data on the national level. This is a gateway to the National Map, a collaborative effort among the USGS and other federal, state, and local partners to improve and deliver topographic information for the Nation. Raw GIS data can also be accessed and downloaded from the USGS National Atlas Raw Data Download site. Another good starting point for nationwide data is data.gov: geospatial. This is the federal government's "one-stop shop" for finding and using geographic data. The data categories important to siting projects that you can browse and download include:
- Environment
- Political Boundaries
- Agriculture
- Atmosphere
- Biology
- Demographic
- Elevation
- Geology
- Imagery and Basemaps
- Inland waters
- Transportation
- Utilities
Try This!
The following link shows you how to use the data.gov portal:- Frequently Asked Question about Data.gov portal: Data.gov FAQ