Solving the mystery of increased hydrogen chloride in the Northern Hemisphere

A very cool achievement. Always nice to have an explanation for something unexpected. (H/T to http://twitter.com/DanWeaver_ca

University of Toronto physicist Kaley Walker has helped solve the scientific mystery behind the recent increase in ozone-depleting chemicals in the lower stratosphere of the Northern Hemisphere, despite a 25-year old ban on chlorofluorocarbons (CFCs).