Zonal Love and Shida numbers estimated by VLBI

Övrigt konferensbidrag, 2013

The deformation of the anelastic Earth as a response to external forces from the Moon and Sun is characterized with proportionality parameters, the so- called Love and Shida numbers. The increasing pre- cision and quality of the VLBI (Very Long Baseline Interferometry) measurements allow determining those parameters. In particular, the long history of the VLBI data enables the estimation of Love and Shida numbers at the low frequencies with the longest period of a tidal wave at 18.6 years. In this study we analyze 27 years of VLBI measurements (1984.0 - 2011.0) following the recent IERS Conventions 2010. In several global solu- tions, we estimate the complex Love and Shida num- bers of the solid Earth tides for the main long-period tidal waves. Furthermore, we determine the Love and Shida numbers of the rotational deformation due to po- lar motion, the so-called pole tide.