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Earth magnetic pole

The geographic position of the Earth magnetic pole and the dipole moment $M_E$ can be calculated from the first three coefficients of the International Geomagnetic Reference Field (IGRF) published 5-yearly by IAGA Working Group 814. For full precision interpolate the values $g_{10},g_{11},$ and $h_{11}$ for the date requested and determine the geographic longitude $\lambda_D$, latitude $\Phi_D$ and moment $M_E$ by (Hapgood, 1997; Kertz, 1969; Hapgood, 1992):
\begin{displaymath}\lambda_D = \arctan( h_{11} / g_{11} ) \hspace{1cm}
\Phi_D = ...
...hspace{1cm} M_E = \sqrt{g_{10}^2 + g_{11}^2 + h_{11}^2}*R_E^3, \end{displaymath} (21)

where $R_E$= 6378.14 km is the Earth equatorial radius and $\lambda_D$ lies in the fourth quadrant.

For the period 1975-2000 we derive following linear approximations with a precision of $0^\circ.05$:

\begin{displaymath}\lambda_D = 288^\circ.44 - 0^\circ.04236y_0 \hspace{1cm}
\P...
...1cm} M_E = 3.01117 - 0.00226y_0 [10^{-6} \mbox{T}\cdot R_E^3], \end{displaymath} (22)

where $y_0$ are Julian years from J2000.0.



Markus Fraenz 2017-03-13