IfSAR High Resolution Elevation

IfSAR - Interferometric Synthetic Aperture Radar is an aircraft-mounted sensor designed to measure surface elevation, which is used to produce topographic imagery.

DEM - A digital elevation model is a representation of the topography of the Earth or another surface in digital format, that is, by coordinates and numerical descriptions of altitude which are used often in geographic information systems (GIS).

DTM - A digital terrain model is a topographic model of the bare earth that can be manipulated programs.  Vegetation, buildings and other cultural features are removed digitally leaving just the underlying terrain.

DSM - A digital surface model is a topographic model of the reflected surface of the earth that can be manipulated by computer programs.  A DSM may include vegetation and man-made structures removed from digital terrain model (DTM).

Coverages available for Alaska:

NPRA - DEM/DTM/DSM