Magnetic field associated with the Earth. It is essentially dipolar (i.e., it has two poles, the northern and southern magnetic poles) on the Earth's surface. Away from the surface, the field becomes distorted. Most geomagnetists explain the field by means of dynamo theories, whereby a source of energy in the Earth's core causes a self-sustaining magnetic field. In the dynamo theories, fluid motion in the Earth's core involves the movement of conducting material within an existing magnetic field, thus creating a current and a self-enforcing field.
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New Geomagnetism and Aeronomy Study Findings Have Been Reported by Scientists at Russian Academy of Science
Oct 12, 2010; "A stable linear relation between foF2 and W with a correlation coefficient of 0.68-0.96 has been revealed as a result of a joint...