  We discuss the stabilisation of the inverse cascade in the large scale
instability of the Kolmogorov flow described by the complete Cahn-Hilliard
equation with inclusion of $\beta$ effect, large-scale friction and deformation
radius. The friction and the $\beta$values halting the inverse cascade at the
various possible intermediate states are calculated by means of singular
perturbation techniques and compared to the values resulting from numerical
simulation of the complete Cahn-Hilliard equation. The excellent agreement
validates the theory. Our main result is that the critical values of friction
or $\beta$ halting the inverse cascade scale exponentially as a function of the
jet separation in the final flow, contrary to previous theories and
phenomenological approach.
