ACE H Kids Organization

If you don’t adjust your Suunto Core with the declination for the area you’re exploring, your compass bearing (direction) will be off in relation to your map. You can find an area’s current declination (stated in degrees east or west) on the margins of a current topographic map.

You should be aware of "magnetic deviation", which are errors induced by local magnetic fields. Sources of error can include cars, ships, variations in the Earth’s crust or mantle, and magnetic rock underfoot. If you’re in the backcountry, a map will typically show any large areas of deviation. If your Suunto Core Compass suddenly goes wacky, move to a different location to see if magnetic rock underfoot is the culprit.