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1. Geomagnetic Coordinates 1940-2015

The GMCORD program provides a determination of the geomagnetic coordinates for any selected global location. The program uses a linear interpolation of the dipole Gauss coefficients from the geomagnetic reference field models (see file ALL-IGRF.TAB below). The fitting allows specification of any date from the first day of January 1940 to the projected values on the last day of December 2015. This program uses a computational method devised by Fraser-Smith (1987) and originally coded by W.H. Campbell. New version coded by Adam Woods. An example screen is shown below.

Example Screen from GMCORD

To run the program, enter the desired latitude and longitude in geographic coordinates (decimal degrees with + for North and East, - for South and West), and answer the date questions (months are to be given as numbers 1 to 12). The displayed output may be saved by using the "print screen" key on your computer.

Download the original version provided by Wallace Campbell

Download linux version with C source code

Download windows version with C source code

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