U.S. Historic Magnetic Declination Estimated Value More information

This program derives a table of secular change in magnetic declination for a specified point in the conterminous United States. It utilizes the USD polynomial until 1984 and then uses the IGRF spherical harmonic model from 1985 on. Declination is shown to the nearest minute so that secular change may be properly illustrated, but it is usually only accurate to within 30 minutes. The calculator provides an easy way for you to get results in HTML, XML, or CSV programmatically (API). Registration is required to access this service. Please register using the API registration link on the top right. `

Calculate U.S. Historic Declination
Latitude: N
Longitude: W
Start Date:
Year
End Date:
Year
Result format: HTML XML CSV
  
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