High-Resolution Orthorectified Imagery from 1985, 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 1985 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. 1:58,000 scale, color
infrared (CIR) photographs acquired by the United States Geological Survery (USGS)
National High Altitude Photography Program (NHAP). 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), and known focal length and
fiducial coordinates from a calibration report. 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 m (RMSE, relative to the 2008 reference
imagery, based on 9 independent check points). The mosaic covers an area of 98 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, 1972, 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.