Latitude, << LAT uh tood, >> describes the position of a point on the earth’s surface in relation to the equator. Latitude is one of the two grid coordinates that can be used to locate any point on the earth. The other coordinate is longitude.
The latitude of a point is measured in terms of its distance from the equator toward one of the earth’s poles. Latitude is measured in degrees. Any point on the equator has a latitude of zero degrees (written 0°). The North Pole has a latitude of 90° north and the South Pole has a latitude of 90° south. These two points are sometimes written +90° and -90°. Degrees of latitude are divided into 60 minutes (‘), and the minutes each consist of 60 seconds (“).
All points on the earth’s surface that have the same latitude lie on an imaginary circle called a parallel of latitude. The distance between two parallels that are 1° apart is about 60 nautical (sea or air) miles, or 69 statute (land) miles or 111 kilometers. This length of 1° of latitude varies from 59.7 nautical miles near the equator to 60.3 nautical miles near the poles. The variation results because the earth is not a perfect sphere. A difference in latitude of 1 minute equals about 1 nautical mile.