| Light Detection and Ranging (LIDAR) is a method of locating objects on the ground
using aerial-borne equipment. It is similar to RADAR or SONAR in that the two-way
travel time of an energy beam reflected off an object is precisely measured, but this
technology uses laser light instead of radio or sound waves. This technology has proven
very useful in remote sensing of the earth. It can be used for determining elevations
of both the earth’s surface and items (natural and man-made) on the surface. Analysis
of LIDAR data is used in detailed modeling of the earth’s surface for drainage and
floodplain studies, determining how a new structure will affect views from various
locations, shoreline erosion studies, and other reasons. This data set contains only
the bare earth mass points. Bare earth points represent ground features. Features
that are above ground, such as buildings, bridges, tree tops, etc, have been eliminated.
Mass points may appear to have "holes" with no elevation values in areas where the
surface could not be determined, such as very dense forests or urban areas.
|