High-Resolution Orthorectified Imagery from 1972, Niwot Ridge LTER Project Area, Colorado

Citation: Manley, W.F.,
Parrish, E.G., and Lestak, L.R., 2009, High-Resolution Orthorectified
Imagery and Digital Elevation Models for Study of Environmental Change at
Niwot Ridge and Green Lakes Valley, Colorado: Niwot Ridge LTER, INSTAAR,
University of Colorado at Boulder, digital media. This image is a mosaic of orthorectified aerial photography from 1972 for the
Niwot Ridge Long Term Ecological Research (LTER) project area at 0.8 m resolution.
The image also covers the Green Lakes Valley portion of the Boulder Creek Critical
Zone Observatory (CZO). The mosaic has the qualities of a photograph and the
functionality of a map layer for use in Geographic Information Systems (GIS) or
remote sensing software. The mosaic is derived from approx. 1:55,000 scale, color
infrared (CIR) photographs acquired by the National Aeronautics and Space
Administration (NASA). The aerial photos were obtained as 1800 dpi digital scans
from the USGS EROS Data Center (EDC) and then fully orthorectified in a Leica
Photogrammetry Suite (LPS) bundle blockfile using an air-photo camera model, a
Digital Elevation Model (DEM), estimated focal length, and hand-measured fiducial
coordinates. Individual photo frames were mosaiced with cutlines and clipped to the
Niwot project extent area. The photography was registered to 2008 orthocorrected
Denver Region Council of Governments (DRCOG) aerial photography. Horizontal accuracy
is 1.7 m (RMSE, relative to the 2008 reference imagery, based on 9 independent check
points). The mosaic covers an area of 77 km2 and is available in GeoTIFF format, in
a UTM zone 13 projection and NAD83 horizontal datum, with FGDC-compliant metadata.
The mosaic is available through an unrestricted public license, and can be obtained
by request (see Distributor contact information below). Other datasets available in
this series includes orthorectified aerial photograph mosaics (for 1953, 1985, 1990,
1999, 2000, 2002, 2004, 2006 and 2008), digital elevation models (DEM's), and
accessory map layers. Together, the DEM's and imagery will be of interest to
students, research scientists, and others for observation and analysis of natural
features and ecosystems. NOTE: This EML metadata file does not contain important
geospatial data processing information. Before using any NWT LTER geospatial data
read the arcgis metadata XML file in either ISO or FGDC compliant format, using
ArcGIS software (ArcCatalog > description), or by viewing the .xml file provided
with the geospatial dataset.