VLBI measures station displacements with high precision. Analysis of all available observations allows detection of even weak tidal signals. Historically one of the first results obtained by VLBI was determination of Love numbers.

I was the first who determined crust displacements induced by polar tide predicted by S. Newcomb in 1891. It was a part of my Ph.D. thesis (1995). Since then I didn't lose interest to this problem.

* Motivation: *

- Whether Love numbers for long periods are as large as theory predicts?
- Are we able to to discriminate between theories of solid earth tides by using VLBI estimates?
- Does uncertainty in computation of solid Earth tides and ocean loading contribute to VLBI error budget?
- What is the best way to compute displacements due to solid Earth tides and ocean loading>?
- Solid Earth tides, ocean loading, nutation, high-frequency Earth orientation variations kinematically similar motion. Is it legitimate to estimate them independently? How uncertainty in a priori model of one effect may influence our parameter estimates of another effect?

- Petrov, L.Y. "VLBI measurements of the crustal deformations induced by the polar motion", Izvestiya, Physics of the Solid Earth, 1998, N3, p.58-61 (In Russian), English translation.
- Software package sotid for computing site displacements due to the solid Earth tides using the frequency domain approach. The algorithm is described in the paper L. Petrov, C. Ma Study of harmonic site position variations determined by VLBI, Journal of Geophysical Research, vol. 108, No. B4, 2190, doi: 10.1029/2002JB001801, 2003.
- Viewgraphs of the presentation Determination of Love numbers H and L for long-period tides using VLBI held at the 14-th Earth tide Symposium in Mizusawa 28-AUG-2000 -- 02-SEP-2000 (Postscript + gzip, 113Kb)
- Viewgraphs of the presentation Combined analysis of VLBI and superconducting gravimeter data held at the 15-th Earth tide Symposium in Ottawa on 02-AUG-2004 (Postscript + gzip, 328Kb)

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* Last update: 20-SEP-2004 15:20:33 *