SERC Data Table of Contents

meta key # modl008
dataset or series of data 1 degree DEM of Chesapeake Watershed Area
keywords digital elevation, model, topography, USGS
originator U.S. Geological Survey
file format ARC/INFO grid
platform Windows NT
study site locale Chesapeake Bay Watershed, USA
beg. date (yyyymmdd) acquired 199703
ongoing? no
end date (yyyymmdd)  
meas. freq.  
site size 90 m2 pixels
# of stations  
west long. -80.633
east long. -74.58
north lat. 43.055
south lat. 36.602
parameters elevation
current sharing status publicly available at edcftp.cr.usgs.gov; /pub/DEM/250
current advertising status advertised by originator
abstract U.S. Geological Survey (USGS) 7.5-Minute Digital Elevation Model (DEM) data are digital representations of cartographic information in a raster form. 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 either from digitized cartographic map contour overlays or from scanned National Aerial Photography Program (NAPP) photographs. DEM data are stored as profiles in which the spacing of the elevations along and between each profile is 30 meters. The number of elevations between each profile differs because of the variable angle between the quadrangle's true north and the grid north of the Universal Transverse Mercator (UTM) projection coordinate system.
additional documentation / reference article http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html

Last Updated on 12/28/00
By Michelle Berger