The solar activity cycle is weakly synchronized with the solar inertial motion

We study possible interrelations between the 300-year record of the yearly sunspot numbers and the solar inertial motion (SIM) using the recently developed technique of synchronization analysis. Phase synchronization of the sunspot cycle and the SIM is found and statistically confirmed in three epochs (1734–1790, 1855–1875 and 1907–1960) of the whole period 1700–2000. These results give quantitative support to the hypothesis that there is a weak interaction between the solar activity and the SIM.