Direct Confirmation of Chandler Wobble Source

Main nonsecular polar motion can be constructed from the current information of its excitation. Since early stages of Earth rotation study, several different sources were suggested as the cause of polar motion. Annual wobble was rather early suspected and confirmed to be driven by Earth's fluid sphere excitation. Chandler wobble was also suspected to be mainly excited by atmosphere and ocean, however, the clear proof was not done until recently. Using a key relation in the frequency domain, polar motion (annual wobble and Chandler wobble) can be directly composed from known information of atmospheric/oceanic/hydrologicexcitations. Similarly, the excited Chandler wobble due to the largest earthquakes (M>8) of the last few decades is found over 30 cm in its maximum diameter. Variation of Chandler wobble amplitude can be approximately explained.