Uses of GPS
| The presence of many satellites in orbit have led to the dramatic development of the Global Positioning System (GPS), which helps measure the position of a receiver anywhere on the Earth's surface relative to several satellites. The orbital parameters of these satellites are extremely well-known; so well-known that multiple measurements of distance can allow a GPS to "triangulate" a receiver's location to very high accuracy, shown here in this animation. While GPS has revolutionized the field of navigation, it has also allowed scientists to map very subtle changes in the Earth surface, as well as allow data collection in the field to be recorded at a very fine scale. For example, a GPS network is now distributed throughout the Los Angeles Basin in order to allow scientists to monitor surface deformation as a precursor to a major earthquake, or detect the changes of the Earth's surface following one. |
Credit: Dylan Prentiss, Department of Geography, University of California, Santa Barbara
For more info: http://www.geog.ucsb.edu/~dylan/mtpe/geosphere/topics/rs/howis.html