Universal Transverse Mercator
Also called: UTM · Topic: Map Projections · NCERT: Beyond NCERT
Meaning
Universal Transverse Mercator (UTM) is a grid system for mapping the earth from 80°S to 84°N. It divides the earth into 60 zones, each 6° of longitude wide. Each zone is drawn on a transverse Mercator projection. This means the cylinder is turned on its side so that it touches the globe along a meridian, not the equator. Because each zone is narrow, distortion stays small. Its grid is metric, so GPS units and GIS layers use it.
Example
India falls in UTM zones 42 to 47. Under the National Map Policy 2005, the Survey of India's Open Series Maps use UTM on the WGS-84 datum, replacing the older polyconic sheets on the Everest spheroid.
Don't confuse with
- Mercator's projection: Mercator's cylinder touches the equator and shows the whole world on one sheet. UTM's cylinder touches a meridian in each of its 60 zones.