LIDAR

LIDAR is an acronym of Light Detection and Ranging, and is a remote sensing technology that uses lasers to determine distance and other information. The main distinction between LIDAR and radar is the use of shorter wavelengths, which are good for imaging objects that do not have significant reflectivity, such as smoke, cloud particles and aerosols, making it especially useful for meteorologists. The USGS and NASA teamed up to use LIDAR to measure volcano deformation, and the accompanying image shows elevation differences in the crater of Mount St. Helens between September 2003 and October 4, 2004 using two airborne LIDAR surveys.