Circle of latitude circle. There are 89 integral (whole degree) circles of latitude between the equator and the Poles in each hemisphere, but these can be divided into more precise measurements of latitude, and are often represented as a decimal degree (e.g. 34.637°N) or with minutes and seconds (e.g. 22°14'26"S). There is no limit to how precisely latitude can be measured, and so there are an infinite number of circles of latitude on Earth. On a map, the circles of latitude may or may not be parallel, and their spacing may vary, depending on which projection is used to map the surface of
Latitude one minute of arc along a meridian of a spherical earth. An ellipsoid model leads to a variation of the nautical mile with latitude. This was resolved by defining the nautical mile to be exactly 1,852 metres. However for all practical purposes distances are measured from the latitude scale of charts. As the Royal Yachting Association says in its manual for day skippers: "1 (minute) of Latitude = 1 sea mile", followed by "For most practical purposes distance is measured from the latitude scale, assuming that one minute of latitude equals one nautical mile". There are six auxiliary latitudes that