|World Magnetic Model 2010
||The World Magnetic Model is the standard model used by the U.S. Department of Defense,
the U.K. Ministry of Defence, the North Atlantic Treaty Organization (NATO) and the
International Hydrographic Organization (IHO), for navigation, attitude and heading
referencing systems using the geomagnetic field. It is also used widely in civilian
navigation and heading systems. The model, associated software, and documentation
are distributed by NGDC on behalf of the National Geospatial-Intelligence Agency (NGA).
The model is produced at 5-year intervals, with the current model expiring on December