Elevation - 3 of 42

Elevation FAQs - 42 Found

How accurate are spot elevations generated by the National Map point query service and viewer/downloader?

The Point Query Service interpolates elevations from the 1/3 arc-second DEM. Interpreted spot elevations are not official and do not represent precisely measured ground surveyed values. Spot elevations derived from National Map DEMs at a specific location might differ from monumented control published on USGS topographic maps or cited in National Geodetic Survey Data Sheets. Variances between interpolated spot elevations and surveyed elevations may be evident for features such as mountain peaks or summits and where the local relief (rate of change of elevation) is more prominent. For most purposes other than engineering, interpolated elevation values are sufficiently accurate.

Tags: Maps, Topographic, Data Products