LiDAR Data Accuracy

LiDAR data are typically compiled to meet a Horizontal Accuracy of 1 meter RMSE. Bare earth topographic LiDAR data are tested to satisfy Non-vegetated Vertical Accuracy (NVA) and Vegetated Vertical Accuracy (VVA), depending on the Quality Level (QL) chosen. Table 1-2 provides these values as a function of the QL selected when using the USGS Lidar Base Specification Version 1.2. VVA will be tested using the 95th percentile for all vegetated land cover categories. LiDAR data are usually tested against a TIN created from the final bare-earth points. Vertical accuracy testing is performed against a TIN as it is unlikely a discrete LiDAR point will be located at the same X/Y location as the survey checkpoints. Note that the NVA and VVA accuracy statistics are affected by bare earth processing, and not necessarily the system calibration.