Data Management Plan

Product: Classified lidar point cloud

The United States Forest Service, Region 6, (USFS) required leaf-on airborne lidar surveys to be collected over of national forestry in Oregon and Washington State. The following areas were requested to be covered: Gifford Pinchot National Forest (GIP) in Vancouver, Washington; Okanogan-Wenatchee National Forest (OKA) in Wenatchee, Washington; Malheur National Forest (MAL) in John Day, Oregon; Deschutes National Forest (DES) in Bend, Oregon, Willamette National Forest (WIL) in Eugene, Oregon, Umpqua National Forest (UMP) in Douglas, Lane, and Jackson Counties, Oregon. The following report applies to the Diamond Lake AOI, which encompasses three hundred twenty three (323) square miles of the Umpqua National Forest in Oregon.

Aerial lidar data for this task order was planned, acquired, processed and produced at an aggregate nominal pulse spacing (ANPS) of 0.35 meters and aggregate nominal pulse density of 8 pulses per square meter.

Process Steps:

• 2018-07-14 00:00:00 - Aircraft and Sensor Information and Flight Plan Execution Atlantic operated a Leica ALS70-HP lidar system on a Cessna (N732JE) for the project area. AAtlantic acquired 247 passes of the AOI as a series of perpendicular and/or adjacent flight-lines executed in 6 flight missions conducted between July 7, 2017 and July 14, 2018. Onboard differential Global Navigation Satellite System (GNSS) unit(s) recorded sample aircraft positions at 2 hertz (Hz) or more frequency. Lidar data was only acquired when a minimum of six (6) satellites were in view.
• 2019-04-29 00:00:00 - Ground Control Survey A total of 34 Non-vegetated Vertical Accuracy (NVA) points were collected in support of this project. Point cloud data accuracy was tested against a Triangulated Irregular Network (TIN) constructed from lidar points in clear and open areas. A clear and open area can be characterized with respect to topographic and ground cover variation such that a minimum of five (5) times the Nominal Pulse Spacing (NPS) exists with less than 1/3 of the RMSEZ deviation from a low-slope plane. Slopes that exceed ten (10) percent were avoided. Each land cover type representing ten (10) percent or more of the total project area were tested and reported with a VVA. In land cover categories other than dense urban areas, the tested points did not have obstructions forty-five (45) degrees above the horizon to ensure a satisfactory TIN surface. The VVA value is provided as a target. It is understood that in areas of dense vegetation, swamps, or extremely difficult terrain, this value may be exceeded. The NVA value is a requirement that must be met, regardless of any allowed 'busts' in the VVA(s) for individual land cover types within the project. Checkpoints for each assessment (NVA and VVA) are required to be well-distributed throughout the land cover type, for the entire project area.
• 2020-10-22 00:00:00 - Lidar Point Cloud Generation Atlantic used Leica software products to download the IPAS ABGNSS/IMU data and raw laser scan files from the airborne system. Waypoint Inertial Explorer is used to extract the raw IPAS ABGNSS/IMU data, which is further processed in combination with controlled base stations to provide the final Smoothed Best Estimate Trajectory (SBET) for each mission. The SBETs are combined with the raw laser scan files to export the LAS (*.las) formatted swath point clouds
• 2020-10-22 00:00:00 - Lidar Calibration Using a combination of GeoCue, TerraScan and TerraMatch; overlapping swath point clouds are corrected for any orientation or linear deviations to obtain the best fit swath-to-swath calibration. Relative calibration was evaluated using advanced plane-matching analysis and parameter corrections derived. This process was repeated interactively until residual errors between overlapping swaths, across all project missions, was reduced to no more than 2 cm. A final analysis of the calibrated lidar is preformed using a TerraMatch tie line report for an overall statistical model of the project area. Upon completion of the data calibration, a complete set of elevation difference intensity rasters (dZ Orthos) are produced. A user-defined color ramp is applied depicting the offsets between overlapping swaths based on project specifications. The dZ orthos provide an opportunity to review the data calibration in a qualitative manner. Atlantic assigns green to all offset values that fall below the required RMSDz requirement of the project. A yellow color is assigned for offsets that fall between the RMSDz value and 1.5x of that value. Finally, red values are assigned to all values that fall beyond 1.5x of the RMSDz requirements of the project.
• 2020-10-22 00:00:00 - Lidar Classification Multiple automated filtering routines are applied to the calibrated lidar point cloud identifying and extracting bare-earth and above ground features. GeoCue, TerraScan, and TerraModeler software was used for the initial batch processing, visual inspection and any manual editing of the lidar point clouds. Atlantic utilized collected breakline data to preform classification for classes 9 (Water) and 20 (Ignored Ground). 1 Processed, Unclassified 2 Ground 7 Low Point (Noise) 18 High Point (Noise)
• 2023-05-12 00:00:00 - Data were received from the U.S. Forest Service Region 6 by the NOAA Office for Coastal Management in LAZ format, Albers USFS Region 6 projection (EPSG:9674), and NAVD88 (Geoid12B) meters vertically. Data were converted to geographic NAD83(2011) coordinates with ellipsoid heights (EPSG:6319) for ingest into the Digital Coast Data Access Viewer. Data were also reorganized such that the LAZ files adhere to the cloud optimized point cloud (COPC) specification for more efficient internet streaming. (Citation: classified lidar data)

Data is available online for bulk or custom downloads

Data is backed up to tape and to cloud storage.