Geostrophic Equations
The geostrophic equations are a simplified form of the Navier–Stokes equations. In particular, it is assumed that there is no acceleration (steady-state), that there is no viscosity, and that the pressure is hydrostatic. The resulting balance is (Gill, 1982):
One special property of the geostrophic equations, is that they satisfy the steady-state version of the continuity equation. That is:
Read more about this topic: Geostrophic Current