Topobathymetric Lidar Survey of Breton and Gosier Islands, Louisiana, January 16 and 18, 2014 - DEM Data

The fundamental and vertical accuracy was tested with 10 bare earth ground control points provided by the USGS. The survey checkpoints were distributed throughout the project area, where appropriate. The Root Mean Square Error (RMSE) of the vertical accuracy of this dataset is 0.03 meters. Additionally, a few ground control points were provided by the USGS in various land cover types. The land classes and number of control points are as follows: Mangroves (1), Short Grass (1), Tall Grass (1), Submerged (4), and Surf Zone (3). Despite the small sample sizes, supplemental vertical accuracy of each land cover type was calculated. All points (bare earth and land cover) were used to calculate the classified vertical accuracy. 0.060 meters Accuracy(z) at 95 percent confidence interval. Fundamental Vertical Accuracy (FVA) was assessed using 10 ground survey points provided by USGS. Elevations from the unclassified lidar surface were measured for the x,y location of each check point. Elevations interpolated from the lidar surface were then compared to the elevation values of the surveyed control. The RMSE was computed to be 0.06 m. Accuracy(z) has been tested to meet 24.5 cm FVA at 95 Percent confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASRPS Guidelines.