Revisiting the period and quality factor of the Chandler wobble and its possible geomagnetic jerk excitation

Abstract

The period and quality factor of the Chandler wobble (CW) are useful for constraining the Earth's internal structure properties, such as the mantle elasticity. It has been shown that the CW is mainly excited by a combination of atmospheric and oceanic processes; hence based on a deconvolution method, we can remove them from the excitation sequence of the CW to estimate its period P and quality factor Q. We finally re-estimate P = 432.3 ± 0.8 days and Q = 85 ± 15 for the CW. Based on those two estimates, we investigate the relationship between the geomagnetic jerks and the excitation sequences of the CW. The geomagnetic jerks or jerk bounds are well consistent with the sudden changes of the excitation sequences of the CW. This demonstrates that the geomagnetic jerks could be a possible excitation source of the CW. It is crucial for understanding the excitation of the CW and for deeper geophysical insights into the geomagnetic jerks.