Excitation of Nonlinear Equilibria in Barotropic Shear Flows
This work shows that transient growth of properly configured small amplitude initial perturbations leads to formation of finite amplitude nonlinear equilibria in barotropic shear flow. It demonstrates the trajectory in phase space leading from linear perturbations to nonlinear solutions.
Farrell, B. F., and A. Y. Hou, 1986: Excitation of nearly steady finite-amplitude barotropic waves. J. Atmos. Sci., 43, 720-728. pdf