Chandler wobble parameters from SLR and GRACE. Issue 6 (11th June 2015)

• Record Type: Journal Article
• Authors: Nastula, J.; Gross, R.
• Is Part Of: Journal of geophysical research. Volume 120:Issue 6(2015:Jun.)
• Page Start: 4474
• Page End: 4483
• Publication Date: 2015-06-11
• Subjects: Chandler wobble parameters -- SLR -- GRACE; Geomagnetism -- Periodicals; Geochemistry -- Periodicals; Geophysics -- Periodicals; Earth sciences -- Periodicals; 551.1
• DOI: 10.1002/2014JB011825
• Languages: English
• ISSNs: 2169-9313

Abstract

Abstract: The period and quality factor Q of the Chandler wobble are functions of the internal structure and dissipation processes of the Earth. Better estimates of the period and Q of the Chandler wobble can therefore be used to better understand these properties of the Earth. Here the period and Q of the Chandler wobble are estimated by finding those values that minimize the power in the Chandler frequency band of the difference between observed and modeled polar motion excitation functions. The observations of the polar motion excitation functions that we used are derived from both space‐geodetic polar motion observations and from satellite laser ranging (SLR) and Gravity Recovery and Climate Experiment (GRACE) observations of the degree‐2 coefficients of the Earth's time‐varying gravitational field. The models of the polar motion excitation functions that we used are derived from general circulation models of the atmosphere and oceans and from hydrologic models. Our preferred values for the period and Q of the Chandler wobble that we estimated using this approach are 430.9 ± 0.7 solar days and 127 (56, 255), respectively. Key Points: The period and Q of the Chandler wobble are estimated from SLR and GRACE data Atmosphere, ocean, and hydrology models were also used Preferred values are the period = 430.9 ± 0.7 days and Q = 127 (56, 255)