NextMap California:
DTM, DSM, DEM Data

Intermap Technologies, Inc. has donated 2 tiles covering areas in covered by the Slate Mountain USGS 7½-minute quadrangle in central Sierra Nevada, including the southern portion of the Blodgett Forest Research Station.

The data were acquired and processed by Intermap as part of the NEXTMap California program, based on Interferometric Synthetic Aperture Radar mapping of California in 2004-2005.

Sample of the data are below for the portion of Slab Creek Reservoir on the American River (this field of view is approx. 4 kilometers in the E-W direction).

Intermap provides three data products:

• Orthorectified Radar Imagery (ORI)
  1-meter resolution/pixel size

• Digital Surface Model (DSM)
  4-meter resolution/pixel size
  ...Related to the "first return" of the radar signal...

• Digital Terrain Model (DTM)
  4-meter resolution/pixel size
  ...The derived "bare earth surface"...

• Contour lines
  ...A dded using ArcMap Spatial Analyst...

• DTM subtracted from the DSM
  ...To show differences in vegetation and other landcover...

Please visit the GIIF in Mulford Hall to explore this data in person, or contact GIIF personnel for more information