Is the ozone layer evenly distributed around the Earth?
No. The amount of ozone above a location on the Earth varies naturally with latitude, season, and from day-to-day. Under normal circumstances, the ozone layer is thickest over the poles and thinnest around the equator. The ozone layer over Canada is normally thicker in winter and early spring; it can vary naturally by about 25 per cent between January and July. Weather conditions can also cause considerable daily variations.
