Using a two-dimensional circulation model the possible influence on the polar ozone column of modifications to lower stratospheric heating rates, both within the polar vortex and in middle latitudes, has been examined. Using reasonable heating rates it is not possible to change the model ozone to reproduce observed ozone losses in Antarctica. If an additional model heating is introduced at, or just before, the end of the southern hemisphere polar night, the time scales are such that appreciable ozone changes do not occur for at least three months.