The Effects of Solid Earth Deformation on Global Ocean Tides



Laplace's Tidal Equations (LTE) are modified to allow for the yielding of the solid Earth to tide generating forces and to the weight of the oceanic tidal column as well as for oceanic gravitational self-attraction. A realistic cotidal-corange chart for the global M2 tide is used to show that the first effect is the order of the astronomical potential itself while the second and third are roughly one order of magnitude smaller. However, the later potential perturbations produce order one effects in the computed tide because they are much richer in high spherical harmonics than is the astronomical potential. The existence of an appreciable solid Earth tide significantly modifies the usual expressions for stored tidal energy, for tidal energy flux and for the rate of working on the oceans by tide generating bodies. An unexpectedly high value of Q(∼ 34) is found for the global M2 tide.