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Links to related web resources go to NOAA's Space Weather prediction Center Now DoD World Magnetic Model Home Links and descriptions of magnetic field models and software go to the Geomagnetic Data Home go to all data and information Answers to Frequently Asked Questions Go to the Space Physics Interactive Data Resource Geomagnetic Data online at NGDC

Magnetic Declination

Magnetic declination Washington, DC Declination (degrees west) at Washington, DC 1750 - 2005

Magnetic declination, sometimes called magnetic variation, is the angle between magnetic north and true north. Declination is considered positive east of true north and negative when west.

As illustrated in the graph to the left, magnetic declination changes over time and with location.

If you would like to learn more about magnetic declination and Earth's changing magnetic field, we recommend visiting NGDC's Answers to Frequently Asked Questions.