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Common 22-year cycles of Earth rotation and solar activity

Published online by Cambridge University Press:  26 February 2010

Yavor Chapanov ,
Jan Vondrák  and
Cyril Ron
Yavor Chapanov
Affiliation:
Central Laboratory for Geodesy, Bulgarian Academy of Sciences, Akad. G. Bonchev Str. Bl.1, Sofia 1113, Bulgaria email: chapanov@clg.bas.bg
Jan Vondrák
Affiliation:
Astronomical Institute, Academy of Sciences of Czech Republic, Boční II, 141 31 Prague, Czech Republic email: vondrak@ig.cas.cz, ron@ig.cas.cz
Cyril Ron
Affiliation:
Astronomical Institute, Academy of Sciences of Czech Republic, Boční II, 141 31 Prague, Czech Republic email: vondrak@ig.cas.cz, ron@ig.cas.cz
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Abstract

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The 22-year oscillations of the Earth rotation due to several geophysical processes in the core-mantle system, oceans, atmosphere and geomagnetic field are excited mainly by 22-year cycles of the solar activity. These geophysical processes produce their own oscillations of the Earth rotation with different periods around 22 years. The direct and indirect influence of the solar activity on 22-year cycles of the Earth rotation are separated from the core effects and corresponding amplitudes are estimated by means of two approaches. The first, direct approach uses extended time series of Wolf's numbers with 22-year cycles, determined by sign alternation of even sunspot cycles. A linear regression between 22-year cycles of UT1 and solar activity is determined and this regression model is used to calculate the UT1 response to the 22-year cycles of the solar activity. The second, indirect approach uses 22-year oscillation of the mean sea level, caused by water evaporation due to variations of the total solar irradiance. The influence of the mean sea level variations on the Earth rotation is calculated by means of an empirical model of global water redistribution. The core-mantle effects on the 22-year UT1 variations are determined by excluding the UT1 response to the solar activity and core angular momentum due to the geomagnetic field variations, according to the solutions from the Special Bureau of the Core (SBC).

Keywords

Sun: activitysunspotssolar-terrestrial relationstime
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 5 , Symposium S264: Solar and Stellar Variability: Impact on Earth and Planets , August 2009 , pp. 407 - 409
Copyright
Copyright © International Astronomical Union 2010

References

Chapanov, Ya. & Gambis, D. 2008, Journées 2008 “Syst. de ref. spat.-temp.”, Dresden, 131–132Google Scholar
Chapanov, Ya. & Gambis, D. 2009, Proc. IAU Symposium 264, This IssueGoogle Scholar
Chapanov, Ya., Vondrák, J., & Ron, C. 2008, Journées 2008 “Syst. de ref. spat.-temp.”, Dresden, 178–179Google Scholar
Ekman, M. 2003, Small Publ. in Hist. Geophys., 12, 31Google Scholar
Stephenson, F. R. & Morrison, L. V. 1984, Phil. Trans. R. Soc. of London, Ser. A., 313, 47–70Google Scholar