-Reprojection of the downloaded DEM's from UTM NAD 27 to UTM NAD
83, Zone 10 North using the bilinear
interpolation option of the "PROJECT GRID" command in Workstation
Arc/Info 8.1 (service pack 1).
* ORIGINAL USGS METADATA ABSTRACT:
The 7.5-minute digital elevation model (DEM) data are digital representations
of cartographic information in a raster form. The DEMs consist of
an array of elevations for ground positions at regularly spaced intervals.
The data are produced in 7.5- by 7.5-minute blocks from either digitized
cartographic map contour overlays of a scanned National Aerial Photography
Program (NAPP) photographs. The DEM data are stored as profiles with
a 10- or 30-meter square grid spacing along and between each profile.
Approximate file sizes are 9.9 megabytes for a 10-meter resolution
and 1.1 megabytes for a 30-meter horizontal resolution. Data profiles
for this product do not always have the same number of elevations
because of the variable angle between true north and grid north in
the Universal Transverse Mercator (UTM)
projection coordinate system. The DEM data for 7.5-minute units correspond
to the USGS 7.5-minute topographic quadrangle map series for all of
the United States and its territories except Alaska."