Magnetic Field Precession?

Question

How many degrees is the magnetic north changing by every year
I notice on some maps the declineation is as much as 3 degrees
Who measures the change over a year and how can I find the current state of MAGNETIC NORTH..(I live in ALBERTA CANADA)

Answer 1

It is not a fixed amount of variation over time. Declination is the difference between magnetic north and True North, which is an arbitrary geographic point.

There is a constant movement of the earth's magnetic north pole. Fortunately for us all, the Canadian Geological Survey keeps track of this constant movement. Here is an illustration of the daily movement:
http://gsc.nrcan.gc.ca/geomag/nmp/daily_mvt_nmp_e.php

Declination also varies according to your position on the earth.
Here is a link to the software I use frequently to calculate declination based on positiion and time:
http://www.resurgentsoftware.com/GeoMag.html

Here is a map that shows the variation in magnetic declination for the entire world for 1995:
http://www.resurgentsoftware.com/GeoMag/magnetic_declination.htm


Here is an online calculator that will give you your declination based on both a date and your latitude and longitude:
http://www.ngdc.noaa.gov/seg/geomag/jsp/Declination.jsp