Overview
- The average extent during the core depletion period of Sept. 7–Oct. 13 was about 7.23 million square miles (18.71 million square kilometers).
- The greatest one-day extent peaked on Sept. 9 at 8.83 million square miles (22.86 million square kilometers), roughly 30% smaller than the 2006 record year.
- The hole began breaking up nearly three weeks earlier than the average over the past decade.
- Researchers say reduced chlorine and bromine from phased-out chemicals drove the improvement, with a weaker polar vortex likely contributing this season.
- Weather balloon data recorded a South Pole low of 147 Dobson Units on Oct. 6, compared with the 2006 record low of 92.