Data Management Plan

Binary point-cloud data were produced for Assateague Island, Maryland and Virginia, post-Hurricane Hermine, from remotely sensed, geographically referenced elevation measurements collected by Quantum Spatial using a Riegl VQ-880-G (532-nm wavelength circular scan and 1064-nm wavelength linear scan) lidar sensor.

Process Steps:

• 2016-11-30 00:00:00 - Quantum Spatial reports the following steps for Lidar Pre-Processing: 1. Review flight lines and data to ensure complete coverage of the study area and positional accuracy of the laser points. 2. Resolve kinematic corrections for aircraft position data using kinematic aircraft GPS and static ground GPS data. 3. Develop a smoothed best estimate of trajectory (SBET) file that blends post-processed aircraft position with sensor head position and attitude recorded throughout the survey. 4. Calculate laser point position by associating SBET position to each laser point return time, scan angle, intensity, etc. Create raw laser point cloud data for the entire survey in *.las format. Convert data to orthometric elevations by applying a geoid correction. 5. Import raw laser points into manageable blocks to perform manual relative accuracy calibration and filter erroneous points. Apply the refraction correction necessary for bathymetric data. Classify ground/bathymetric points for individual flight lines. 6. Using ground classified points per each flight line, test the relative accuracy. Perform automated line-to-line calibrations for system attitude parameters (pitch, roll, heading), mirror flex (scale) and GPS/IMU drift. Calculate calibrations on ground classified points from paired flight lines and apply results to all points in a flight line. Use every flight line for relative accuracy calibration. 7. Adjust the point cloud by comparing ground classified points to supplemental ground control points.
• 2016-11-30 00:00:00 - Quantum Spatial reports the following steps for Lidar Post-Processing: 1. Classify data to ground and other client designated classifications using proprietary classification algorithms. 2. Manually QC data classification 3. After completion of classification and final QC approval, calculate density information and verify final accuracy calculations for the project using ground control quality check points.
• 2019-06-24 00:00:00 - Data were received from Xan Fredericks of the USGS in LAS 1.4 format compressed with laszip as LAZ files. Data were converted from UTM coordinates with NAVD88 (GEOID12B) heights in meters to geographic coordinates and ellipsoid heights. Data were then ingested into the Digital Coast Data Access Viewer system. (Citation: USGS hosted original data)

Data is available online for custom downloads