In the static magnetic field day to day changes are mainly in response to solar and lunar tides, etc., but also in response to the electromagnetic space activities.
The change of earth's electric field in the magnetic static day mainly responds to the tides of the sun and the moon, and also to the electromagnetic activity of space.
The diurnal variation of the geoelectric field on the magnetostatic day mainly responds to the tides of the sun and the moon, as well as the electromagnetic activities in space.<br>