On the frequency variations in the Earth’s rotation caused by unstable flows in the liquid core

Resumo

The correlation between frequency variations in the Earth’s rotation and geomagnetic jerks is analyzed on the interval from 1900 to 2008. It is found that jerks precede changes in the rate of the Earth’s rotation frequency in the interval of periods ranging from 5 to 8 years. A mechanism of jerks generation is suggested in which the jerks are considered as the result of the excitation of magnetorotational instability in the Earth’s core with the subsequent generation of torsional oscillations causing a change in the Earth’s rotation frequency.