Parameter defined by the axis of the geomagnetic dipole
Geomagnetic latitude, or magnetic latitude (MLAT), is a parameter analogous to geographic latitude, except that, instead of being defined relative to the geographic poles, it is defined by the axis of the geomagnetic dipole, which can be accurately extracted from the International Geomagnetic Reference Field (IGRF).[1] Further, Magnetic Local Time (MLT) is the geomagnetic dipole equivalent to geographic longitude.[2]
^VanZandt, T. E.; W. L. Clark; J. M. Warnock (1972). "Magnetic apex coordinates: A magnetic coordinate system for the ionospheric F2 layer". J. Geophys. Res. 77 (13): 2406–2411. doi:10.1029/JA077i013p02406.