Short‐lived bromine compounds in the lower stratosphere; impact of climate change on ozone

We consider how future changes in the circulation of the troposphere might change the delivery of short‐lived brominated species to the stratosphere and study the impact of this change on stratospheric ozone. Changes in stratospheric bromine are potentially significant, amounting, under an extreme scenario of all short‐lived species having a tropical source, to an increase of perhaps 10% above current levels. This must be set against the slow removal of anthropogenic halogens from the stratosphere. These changes lead to modest, but non‐negligible decreases in ozone in the lower stratosphere, reaching about 8% at the tropopause, where changes in ozone have important climate consequences.