1 00:00:00,040 --> 00:00:04,160 NASA and NOAA have tracked seasonal changes in the hole in the ozone layer over Antarctica since 1985. 2 00:00:04,160 --> 00:00:08,200 3 00:00:08,200 --> 00:00:12,240 4 00:00:12,240 --> 00:00:16,260 Ozone depletion occurs faster in cooler temperatures, so the ozone hole reaches an annual maximum at the end of southern hemisphere winter. 5 00:00:16,260 --> 00:00:20,290 This year, the ozone hole reached its annual maximum on September 11. 6 00:00:20,290 --> 00:00:24,450 7 00:00:24,450 --> 00:00:28,500 It was the smallest maximum since 1988, partly due to warmer global temperatures. 8 00:00:28,500 --> 00:00:32,640 9 00:00:32,640 --> 00:00:36,730 10 00:00:36,730 --> 00:00:37,440