SUUNTO Core - Manual (Page 40)

8.1.2 Setting declination value
Paper maps point to true North. Compasses, however, point to magnetic North
– a region above the Earth where the Earth’s magnetic fields pull. Because
magnetic North and true North are not at the same location, you must set the
declination on your compass. The angle in between magnetic and true north
is your declination.
The declination value appears on most maps. The location of magnetic North
changes yearly, so the most accurate and up-to-date declination value can be
obtained from the internet (for example the National Geophysical Data Center
for the USA).
Orienteering maps, however, are drawn in relation to magnetic North. This
means that when you are using orienteering maps you need to turn the
declination correction off by setting the declination value to 0 degrees.
To set the declination value:
1. In MENU , select COMPASS .
2. Turn the declination off or choose W (west) or E (east).
3. Set the declination value with [+] and [- Light].
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