“Laplace derived the differential equations for a thin fluid on a sphere with no vertical motion, only horizontal motions, called a barotropic model. Ocean tides are caused by the horizontal gravitational force of Moon and Sun. The Earth rotates so we have Corriolis forces. A slope in the sea-surface also causes horizontal force. Bottom friction and/or lateral eddy dissipation.” Thus you can use the equation to compute for the ocean tides.


Source: http://wakes.uma.pt/cimar/PartII_lecture1.pdf