Hole in ozone layer unusually small this year

Scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA) have found that the hole in the ozone layer, which usually appears at this time of year, is much smaller that it was in 2000 and 2001. The reason, they say, is this year’s peculiar stratospheric weather patterns resulting from warmer than normal temperatures around the edge of the polar vortex and not part of a long-term trend. They also note that the data is not conclusive that the ozone layer is recovering.

“The Southern Hemisphere’s stratosphere was unusually disturbed this year,” said Craig Long, meteorologist at the NOAA’s Climate Prediciton Center. “This is the first time we’ve seen the polar vortex split in September.”

In past years concern has been expressed about the large size of the Antarctic ozone hole (see related story). In 2000, NASA revealed that the hole was three times larger than the US. However, recent reports have been more optimistic, with one revealing that the Montreal Protocol, the international treaty to cut the emission of ozone depleting substances, is working (see related story), and a second stating that the ozone layer could recover by 2040 (see related story).