Abstract: LIDAR data is remotely sensed high-resolution elevation data collected by an airborne collection platform. Using a combination of laser rangefinding, GPS positioning and inertial measurement technologies; LIDAR instruments are able to make highly detailed Digital Elevation Models (DEMs) of the earth's terrain, man-made structures and vegetation. This data was collected at submeter resolution to provide nominal 1m spacing of collected points. Two returns were recorded for each pulse in addition to an intensity value.
Purpose: LIDAR data is used for 3D visualization, elevation based analysis and for feature extraction.
Supplemental Information: Reflective surface data represents the DEM created by laser energy reflected from the first surface encountered by the laser pulse. Some energy may continue beyond this initial surface to be reflected by a subsequent surface as represented by the Last Return data. Intensity information is captured from the Reflective Surface pulse and indicates the relative energy returned to the sensor as compared to the energy transmitted. The Intensity image is not calibrated or normalized but indicates differences in energy absorption due to the interaction of the surface materials with laser energy at the wavelength transmitted by the sensor. Points are classified as on ground surface or not on ground surface to support creation of a bare earth model from the data. Open water is classified as not bare ground. The 2004 Connecticut Lidar Data Validation Report may be viewed at ftp://ftp.csc.noaa.gov/pub/crs/beachmap/qa_docs/ct

Progress: Complete
Update Frequency: None planned

Theme Keywords: ISO 19115 Topic Categories , Elevation , None , Elevation , Lidar , Laser , Beach , Bathymetry/Topography , Digital elevation model , DEM , Erosion
Place Keywords: US , Connecticut , Long Island Sound , Quinnipiac River , New Haven Harbor , Connecticut Coastline , Connecticut River , New Haven , Old Saybrook

Access Constraints: None
Usage Constraints: Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations.