The steady incompressible shearing sheet equation is
The final term follows from the local tidal potential . For the given linear velocity, the advective acceleration is , while the Coriolis acceleration is . Equating components gives
The cross derivatives vanish, so the pressure Hessian of an elliptical shearing-sheet vortex integrates to
The additive constant is fixed by exterior matching or the pressure reference. No zero-pressure free-boundary condition is imposed on an incompressible vortex patch: it is embedded in a surrounding fluid.