LIght Detection And Ranging. LIDAR gathers data through laser light striking the surfaces of the earth and measuring the time of pulse return A LIDAR system is often capable of recording up to five (5) returns per pulse
A ‘point cloud’ of multiple LIDAR returns…a topic for on-going research… estimating forest stand volume for example
The most common use for LIDAR is the creation of very high resolution DEM’s
Conceptually quite simple, a single laser beam sweeps back and forth beneath an aerial (or space) platform.
As the velocity of light is a constant, the time from pulse to recording provides a very accurate measure of height
Accurate LIDAR data is completely dependent on being able to know, and correct for changes in platform orientation.
IR and visible wavelengths both measure aerosols and clouds. Two UV wavelengths determine the profile of ozone by analyzing the absorption differences due to ozone between the two lidar returns. “