The dataset contains detailed Digital Elevation Models (DEMs), generated from Airborne LiDAR. The data is owned by the Environment Agency and is provided to BGS for research use only. Very limited UK coverage, limited mostly to floodplains. Light Detection and Ranging (LiDAR) is an airborne mapping technique which uses a laser to measure the distance between the aircraft and the ground. This technique results in the production of a cost-effective terrain map suitable for assessing flood risk. The aircraft flies at a height of about 800 metres above ground level and a scanning mirror allows a swathe width of about 600 metres to be surveyed during a flight. Individual measurements are made on the ground at 2 metre intervals allowing a highly resolved model of the terrain to be generated. The Agency's Flood Defence function has a requirement under the Water Resources Act 1991 to monitor the flood plain. LiDAR is being used to measure land topography and assess coastal erosion and geomorphology. Products that can be generated from the LiDAR data include colour coded elevation models, height contour plots and three-dimensional perspective views allowing easy visualisation of surveyed areas.
