Pole

1600 km

The strength and direction of the Earth's magnetic field are constantly changing. Scientists monitor these changes and track the location of the magnetic north pole, which is not fixed at a specific geographic location. The magnetic north pole moves by a significant but variable amount from day to day and year to year (on the order of 40 kilometers or 25 miles). Compass directions, which are based on the earth's magnetic field, must be converted to true directions, by applying corrections to account for the variations in the strength and location of the magnetic north pole, since maps and navigation are oriented to the location of the true (geographic) North Pole. :)+