What about the other pole? The ozone layer is damaged over the Arctic too, though we don’t usually see the same kind of ozone depletion there as over Antarctica. The reason is that Arctic stratosphere is not as cold, and air doesn’t get trapped as tightly there (think of northern cold fronts spinning south out of Canada). But there are exceptions. 1997 was a bad spring for Arctic ozone. And this spring, the World Meteorological Organization reports, ozone levels over the Arctic dropped 40 percent to record low levels . The Arctic stratosphere was unusually cold this winter – in part because the lower atmosphere over the Arctic was unusually warm . Scientists expect recovery of the Arctic ozone layer between 2020 and 2035. Due to broader climate changes, Arctic ozone concentrations may keep increasing through this century.