Comment on Expanding domain limit for incompressible fluids in the plane, Communications in Mathematical Physics, 278(3):753-773, 2008

The argument that obtains the modulus of continuity of the inverse flow map following (8.12) (on page 767 in the published version) is written as though, in effect, the velocity field is time-invariant; that is, the ODE defining the flow map is autonomous. The argument should use a more careful version of the inverse flow map in each step of the proof, yielding the same bound, as done, for instance, on pages 318-319 of Majda and Bertozzi's 2002 text. Or see flow maps estimates for a non-autonomous vector field.