A mathematical model is developed to study the free (frictionless) steady horizontal flow which can occur in a homogeneous ocean of constant depth. The flow satisfies the dynamic constraint that the vertical component of absolute vorticity is constant along a streamline....
Fofonoff, N. P.. 1955. "Steady flow in a frictionless homogeneous ocean." Journal of Marine Research 13, (3). https://elischolar.library.yale.edu/journal_of_marine_research/818