This data set contains topographic and bathymetric lidar data that were collected on April 21, 23, 30, May 2, and June 14, 17 of 2003,
cooperatively by the U.S. Geological Survey (USGS), National Aeronautics and Space Administration (NASA), and National Park Service (NPS).
The data is for part of the U.S. Virgin Islands (island of St. John and a portion of the northern coastline of St. Croix). The bathymetric lidar
data are classified as 11 and the topographic lidar data are classified as 0.
A first surface and submerged topography elevation map (also known as a Digital Elevation Model, or DEM) of a portion of the U.S. Virgin Islands
(island of St. John and a portion of the northern coastline of St. Croix) was produced from remotely sensed, geographically referenced
elevation measurements cooperatively by the U.S. Geological Survey (USGS), National Aeronautics and Space Administration (NASA), and National
Park Service (NPS).
Elevation measurements were collected over the area using the NASA Experimental Advanced Airborne Research Lidar (EAARL), a pulsed-laser
ranging system mounted onboard an aircraft to measure ground elevation, vegetation canopy, and coastal topography. The system uses high
frequency laser beams directed at the Earth's surface through an opening in the bottom of the aircraft's fuselage. The laser system records
the time difference between emission of the laser beam and the reception of the reflected laser signal in the aircraft. The plane travels over
the target area at approximately 50 meters per second at an elevation of approximately 300 meters. The EAARL, developed by NASA at Wallops
Flight Facility in Virginia, measures ground elevation with a vertical resolution of 15 centimeters. A sampling rate of 3 kilohertz or higher
results in an extremely dense spatial elevation dataset. Over 100 kilometers of coastline can be surveyed easily within a 3- to 4-hour mission.
When subsequent elevation maps for an area are analyzed, they provide a useful tool to make management decisions regarding land development.
Original contact information:
Contact Name: Amar Nayegandhi
Contact Org: Jacobs Technology, U.S. Geological Survey, FISC, St. Petersburg, FL
Title: Computer Scientist
Phone: 727-803-8747 (x3026)
Email: anayegandhi@usgs.gov
This data set is an LAZ (compressed LAS) format file containing LIDAR point cloud data.