What is the angle between geographic north and the north to which a compass needle points?

Answer 1

The sum of variation and deviation. The angle of magnetic declination, or magnetic variation, is the angle between the local magnetic field lines with which a magnetic compass needle lines up and the direction of true north, the north axis point of Earth. In the U.S., that angle varies between 0 degrees and about 20 degrees and also varies over time.
The difference between "true" north and "magnetic" north is called "magnetic variation", which is often abbreviated as "mag var".

The north magnetic pole is in northern Canada, but is continually (although slowly) moving. Topographical or navigational maps are generally overprinted with "mag var" lines and the amount of correction.

Answer 2

The angle between geographic north and magnetic north, to which a compass needle points, is known as magnetic declination. It varies depending on your location on the Earth's surface and can be either east or west of true north. It is important to account for this difference when using a compass for navigation.