Declination

To understand declination you must first realize that there are two North Poles. There is a True Geographic North Pole at the top of the world, and a Magnetic North Pole which is over 1,250 miles from the True North Pole. A magnetic compass always points toward the Magnetic North Pole. Maps are oriented to the True North Pole. The angular difference between True North Pole and Magnetic North is called declination. Declination varies from 0 to 30 degrees in most populated regions of the world. These declination values usually change slightly over time, as the earths plates shift. The actual value of declination and its annual rate of change for your area will usually be shown on your map. This will be expressed as either a Easterly or Westerly declination, depending on your location.

Magnetic North Pole		Declination