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This is a non-bare earth data set. ASCII xyz point cloud data were produced from remotely sensed, geographically referenced elevation measurements cooperatively by the U.S. Geological Survey (USGS) and National Aeronautics and Space Administration (NASA) along the coasts of Alabama, Florida (Panhandle), Louisiana, Mississippi and Texas in 2001. Dates of collection are: 1. Alabama 20011002-20011004, 20011007-20011010 2. Florida 20011002 3. Louisiana 20010909-20010910 4. Mississippi 20010909-20010910 5. Texas 20011012-20011013 Elevation measurements were collected over the area using the NASA Airborne Topographic Mapper (ATM), a scanning Lidar system that measures high-resolution topography of the land surface. The ATM system is deployed on a Twin-Otter or P-3 Orion aircraft and incorporates a green-wavelength laser operating at pulse rates of 2 to 10 kilohertz. Measurements from the laser ranging device are coupled with data acquired from internal navigation system (INS) attitude sensors and differentially-corrected global positioning system (GPS) receivers to measure topography of the surface at accuracies of 10 to 20 centimeters.