Polar Regions
In the polar regions, a different convention is used. South of 80°S, UPS South (Universal Polar Stereographic) is used instead of a UTM projection. The west half-circle forms a grid zone with designation A; the east half-circle forms one with designation B; see figure 3. North of 84°N, UPS North is used, and the west half-circle is Y, the east one is Z; see figure 4. Since the letters A, B, Y, and Z are not used for any latitude bands of UTM, their presence in an MGRS coordinate, with the omission of a zone number, indicates that the coordinates are in the UPS system.
The lettering scheme for 100,000 m squares is slightly different in the polar regions. The row letters go from A to Z, omitting I and O. The column letters use a more restricted alphabet, going from A to Z but omitting I, O, D, E, M, N, V, W; the columns are arranged so that the rightmost column in grid zone A and Y has column letter Z, and the next column in grid zone B or Z starts over with column letter A. The restricted column alphabet for UPS ensures that no UPS square will be adjacent to a UTM square with the same identification.
In the polar regions, there is only one version of the lettering scheme.
Read more about this topic: Military Grid Reference System
Famous quotes containing the words polar and/or regions:
“In time your relatives will come to accept the idea that a career is as important to you as your family. Of course, in time the polar ice cap will melt.”
—Barbara Dale (b. 1940)
“Nature seems to have taken a particular Care to disseminate her Blessings among the different Regions of the World, with an Eye to this mutual Intercourse and Traffick among Mankind, that the Natives of the several Parts of the Globe might have a kind of Dependance [sic] upon one another, and be united together by their common Interest.”
—Joseph Addison (1672–1719)