Pangolin

Magnetic Variation

Magnetic data for: 0°0'N 0°0'E:
(Set/reset your local values)

The MagVar Applet

Move the cursor to any point on the map to find its current magnetic variation. Click the left (or right) mouse button to mark a start position (dark green spot). Click it again to mark a destination (red spot) and plot the great circle track. The distance and initial bearing appear in text boxes at the bottom of the chart. Double click either mouse button to clear the chart. These procedures are a simplified version of those provided in the the Offshore Almanac.

MarVar's routines for computing magnetic variation were derived from a Fortran program called GEOMAG, kindly provided by the United States, National Geophysical Data Center (NGDC). Users should be aware that it is an unofficial product and unsupported.

Accuracy
In general accuracy is within half a degree, though no account is taken of local magnetic anomalies which can exceed ten degrees though this is unusual. For further details, see the NGDC web site.

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