2.8: Universal Transverse Mercator (UTM)

Universal Transverse Mercator (UTM)

UTM Links to an external site. is another coordinate system that can be used to determine a location. It is most commonly used for military, research and survey applications. The UTM system divides the earth’s surface into a grid. Each grid is identified by a number across the top called the zone number Links to an external site. and a letter down the right hand side called the zone designator (Figure 2.11). For example: Los Angeles, CA is in UTM grid 11S.

Every spot within a zone can be defined by a coordinate system that uses meters. Your vertical position is defined in terms of meters north (Northing) and your horizontal position is given as meters east (Easting) shown in Figure 2.12. Along the borders of a topographic map you will find both latitude and longitude, and the northing and easting coordinates. The UTM coordinates can be identified by their unique formatting and mixture of font sizes.

Note that in Figure 2.12, the latitude and longitude are designated by positive and negative numbers, with a positive latitude indicating position in the northern hemisphere and a negative latitude indicating position in the southern hemisphere. Similarly, a positive longitude indicates the eastern hemisphere and a negative longitude represents the western hemisphere.)