geomagnetic coordinates

geomagnetic coordinates

[¦jē·ō·mag¦ned·ik kō′ȯrd·ən·əts]
(geophysics)
A system of spherical coordinates based on the best fit of a centered dipole to the actual magnetic field of the earth.
References in periodicals archive ?
When using this dipole model, the computational coordinate system is a geomagnetic coordinate system, and the Earth's magnetic field is defined in geomagnetic coordinates.
Thus, the Earth's magnetic field is represented by a dipole model, which is eccentric (centred) in the geographic (geomagnetic) coordinate system, and the mean value of magnetic gyrofrequency is calculated as an integral of gyrofrequency referred to the geomagnetic coordinates. At ionospheric heights, that is, h [much less than] [R.sub.T], the gyrofrequency [[omega].sub.H] is almost independent from the height h and at middle geographic latitudes [pi]/2 - [theta] = [pi]/2 - [lambda] - ([pi]/180[degrees])[DELTA][theta] such that -[pi]/4 < [pi]/2 - [theta] < [pi]/4, it is almost constant: [w.sub.H](h, [lambda]) [congruent to] <[[omega].sub.H]> (<[f.sub.H]> = <[[omega].sub.H]>/2[pi] [congruent to] 1.2 MHz) [9].