What is the coverage area of NED 1/3 arc second data?
A. The coverage area is approximately 70% of the United States. There are several methods to identify NED 1/3 arc second coverage area. • Go to the Data Source Index. Click on the resolution layer, on the right side of the map. Then Refresh the map. Colors will be diplayed on the map for the different resolutions. Click on the Legend to show the colors and correspondig resolutions. • Go to The National Map Seamless Server on the right side of the map interface, under the Display tab, click the arrow next to the category Layer Extent. A list of layers will appear, find 1/3″ NED Index and click the box next to it. This will automatically update the map with the index showing areas of coverage.
