Load Tide Correction
Load Tide Correction
The load tide describes the vertical displacement of the solid
earth beneath the weight of the overlying ocean tide. The load tide
must therefore be consistent with the model used for the ocean tides.
The load tide is here modeled as a purely elastic
response to ocean loading, using a high-degree expansion in spherical
harmonics (to degree and order 360). The response of each degree depends
on the loading Love number h'n ;
these have been adopted from the
calculations by Farrell (Reviews of Geophysics and Space Physics,
10, 761-797, 1972). Further detailed descriptions of this method of
computing the load tide can be found in:
Ray & Sanchez, ``Radial Deformation of the Earth by Oceanic Tidal Loading,''
NASA Technical Memorandum 100743, 49 pp., July 1989.
The amplitude of the M2 load tide, in millimeters, is shown in the
chart. The largest amplitudes reach 5 cm off the coast of Brazil.
For the diurnal load tides, the largest amplitudes are in the northern
Pacific (e.g. the Gulf of Alaska) and off the coast of Antarctica;
in these regions the K1 load tide reaches nearly 3 cm.
