Dependance of Magnetic Field Variations on the Speed of the Earth’s Rotation

The relationship between the induction of the Earth’s magnetic field and the speed of the Earth’s rotation was analyzed. We used data from mid-latitude magnetic observations at the Mikhnevo Geophysical Observatory of the Sadovsky Institute of Geospheric Dynamics of Russian Academy of Sciences, and the BEL, HAD, MMB, and LYC observatories of the international INTERMAGNET network and data on the unevenness of the Earth’s rotation. It was shown that in the cases considered the induction of the geomagnetic field increases with the growth of the Earth’s rotation speed and, vice versa, decreases with the speed drop. We obtained the quantitative relationship between the absolute magnitude of the geomagnetic field induction vector and the LOD equal to the difference between the observed and ephemeris duration of the day.