The 2000 ozone hole reached its greatest extent in early September at 28.4 million square kilometres and was the largest ever-recorded ozone hole. It reached this maximum extent unusually early, as the hole is normally largest in late September. Minimum ozone values were measured in early October and were amongst the lowest on record. The edge of the ozone hole passed over the tip of South America and the Falkland Islands for significant periods between October 6 and 24. The hole also closed in unusually early and the event was essentially over by early December.
Satellite imagery gives a global perspective on the ozone hole.
TOMS values are close to ground-based values. Stratospheric clouds were sighted from Vernadsky, Rothera and Halley. A mini ozone hole, with central values below 200 DU, periodically formed to the east of the Antarctic Peninsula over the Weddell Sea during July. This mini ozone hole probably formed due to processing of ozone through PSCs, which are far enough north to be sunlit. The feature was particularly marked on July 10 and again on July 20.