Chandler wobble: two more large phase jumps revealed
Zinovy Malkin, Natalia Miller
(Submitted on 26 Aug 2009)
Investigations of the anomalies in the Earth rotation, in particular, the polar motion components, play an important role in our understanding of the processes that drive changes in the Earth’s surface, interior, atmosphere, and ocean. This paper is primarily aimed at investigation of the Chandler wobble (CW) at the whole available 163-year interval to search for the major CW amplitude and phase variations. First, the CW signal was extracted from the IERS (International Earth Rotation and Reference Systems Service) Pole coordinates time series using two digital filters: the singular spectrum analysis and Fourier transform. The CW amplitude and phase variations were examined by means of the wavelet transform and Hilbert transform. Results of our analysis have shown that, besides the well-known CW phase jump in the 1920s, two other large phase jumps have been found in the 1850s and 2000s. As in the 1920s, these phase jumps occurred contemporarily with a sharp decrease in the CW amplitude.
Journal reference: Earth Planets Space, 2010, v. 62, No. 12, 943-947
Bingo!!! Five for five!
2005 is clearly Bush’s fault. 1920 is presumably his grandfather’s fault. 1850 is probably the fault of his great-great-great-grandfather James Smith Bush.