The largest ozone losses ever recorded over the Arctic have been measured by an international network of over 30 ground-based stations and satellite-borne sensors during January-March 2011. We study whether this was an exceptional event or whether it is part of the evolution of an ozone hole in the Arctic. The main finding is that the 2010-2011 winter's record-breaking ozone loss was instigated by the extremely low stratospheric temperatures that are linked to climate change, that is, the coldest winters at the Arctic region have been getting colder leading to larger ozone losses there, which are progressively reaching the levels of the Antarctic ozone hole.
Varotsos, C. A., Tzanis, C., & Cracknell, A. P. (2012). The exceptional ozone depletion over the Arctic in January-March 2011. Remote Sensing Letters, 3(4), 343-352. https://doi.org/10.1080/01431161.2011.597792