Airborne Lidar

Airborne lidar is laser ranging flown on a crewed aircraft or large UAV to map elevation along the coast. A scanning pulsed laser, often a 1064 nm near-infrared channel for land plus a 532 nm green channel for water penetration, times the return to fix surface height to roughly 10 to 15 cm vertical accuracy at point densities of several per square meter. Bathymetric lidar reads the seabed where the water is clear, typically to depths near two to three Secchi depths, around 10 to 50 m. The product fills the white-ribbon gap between vessel-based hydrographic survey offshore and topographic survey ashore, where keels and aircraft both struggle.