LIDAR

LIDAR stands for "Light Detection And Ranging". With LIDAR you can: measure distance; measure speed; measure rotation; and measure chemical composition and concentration. Light Detection and Ranging (LIDAR) is a remote sensing system used to collect topographic data.

This technology is used by the National Oceanic and Atmospheric Administration (NOAA) and NASA scientists to document topographic changes along shorelines, as illustrated in the LIDAR image below of Hilton Head, South Carolina:

In remote sensing, false color images are common. They serve as a means for visualizing data. The term "false color" refers to the fact that these images are not photographs. Rather, they are digital images in which each image pixel represents a data point that is colored according to its value. So, in LIDAR elevation maps, each pixel represents a certain elevation and is colored on the map accordingly to the color that corresponds to that particular elevation.
http://www.csc.noaa.gov/products/sccoasts/html/images/lhilt.gif