LiDAR is high accuracy, high resolution elevation
data derived from airborne sources.
LiDAR (Light Detection and Ranging) uses a laser to measure the distance between the aircraft and ground and between the aircraft and the vegetation canopy or building tops.
Lidar data, similarly to 5m Height Data, are provided in the form of a regular grid of points at 1 or 2m intervals with +/- 0.15m vertical accuracy. Each point has X, Y and Z coordinates in the British National Grid represented as 6 + 2 digits that gives theoretical positioning precision of 0.01m. For example 530871.00
Digital Surface Model (DSM) – is a topographic model of the earth’s surface that includes buildings, vegetation, roads, and natural terrain features. The key benefit of the DSM is that it provides a geometrically correct base map.
Digital Terrain Model (DTM) – is a topographic model of the bare earth that has had vegetation, buildings, and other cultural features digitally removed, enabling users to infer terrain characteristics possibly hidden in the DSM.