The North Pole moves as ice sheets melt (Greenland is losing mass)

[HooptieWagon]

13. OK, a brief rundown.

Magnetic variation is the differrence between the magnetic north pole, and the geographic north pole. It varies widely, in some locations its zero, I've seen it be 30 deg in my sailing...possible its even more in higher latitudes. Depending on location, it either decreases or increases by a small annual amount...usually a few minutes annual change (average 5). Most small boats use magnetic compasses, ships use gyro-compasses because the large amount of steel causes excessive deviation (compass innaccuracy)...I would assume large aircraft do too. Small aircraft might use either. I would assume that the magnetic pole would continue its shifts in the current fairly predictable manner. However, longitude and latitude are NOT based on magnetic north, but on geographic north...the axis of rotation....and it is the geographical pole that concerns us in navigation.
The article seems to be saying that its the geographical pole that is starting to change. In that case, bodies used for navigation (be they sun, stars, or GPS satelltes) no longer have the same orientation to the earth's axis of rotation as previously. This throws off charts, navigation tables, and the computers in your GPS unit. Since 1 minute of latitude is 1 natical mile, even a slight shift in the geographic pole would create a large error in calculating your position.