Science Update: Chemical composition and severe ozone loss during the 2010/2011 Arctic winter

A new paper by R. Hommel and co-authors in ACPD focuses on the exceptionally high ozone loss that occurred during the 2010/2011 Arctic winter. Using both satellite and ground-based observations they examine the composition and transformations occurring in the Arctic polar vortex. A chemical transport model is also used to compare 2011 winter-spring conditions with previous years. The observations show that between ~16–20km ozone is depleted by more than 70%, in comparison with the only slightly more than 20% that occurred in below 20km previous winters. The large ozone loss was found to result from halogen-driven catalytic destruction cycles, activated by the large volume of polar stratospheric clouds generated during the 2010/2011 winter-spring period. Prior to the catalytic cycles being fully effective (mid-January 2011), ozone loss of up to 60% was already observed below ~19km, and is thought to result from meteorological changes resulting in this “mini-hole” event. Such events are expected to increase in frequency as anthropogenically-induced climate change evolves. The full abstract can be found here.