Nature 254, 314 - 315 (27 March 1975); doi:10.1038/254314a0

Is the Earth tide phase lag unaffected by anelasticity?

B. BODRI

Department of Geophysics, L. Eötvös University, Budapest, Hungary

THE dynamics of the Earth−Moon system raises the question whether the bodily tides or ocean tides in the Earth−Moon system produce most of the energy dissipation which is necessary to account for the secular retardation of the rate of rotation of the Earth. Macdonald¹ has shown that a phase lag of 2° of bodily tides is enough to account for the whole change, and in principle this phase lag could be obtained from earth tide observations. In practice, however, the determination of the phase lag of Earth tides is extremely uncertain, since the true value of the delay is influenced by the lag of recording instruments and by several disturbing effects. Pariisky² found that the mean value of the phase lag of solid Earth tides in Europe and in Asia is approximately equal to that of mentioned above, but the individual values are so much different one from another that the averaging is rather uncertain. The study reported here indicates that all of the phase lag derived from Earth tide observations may be instrumental in origin.

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