Cheryl Santa Maria, staff writer
October 25, 2012 — The area covered by the ozone hole in the Antarctic has reached its second smallest size in two decades, NASA and the National Oceanic and Atmospheric Administration (NOAA) have announced.
The hole in the ozone layer over Antarctica appears to be shrinking.
NASA and NOAA satellites captured daily images of the ozone layer, which helps protect the earth from damaging UV rays, between July 1 and October 19 of this year.
According to their data, the hole reached a maximum size of 21.2 million square kilometres on September 22 -- more than double the size of Canada.
So far, the hole's average size in 2012 has been 17.9 million square kilometres, a significant reduction from the all-time high of 29.9 million square kilometres recorded on September 6, 2000.
"The ozone hole mainly is caused by chlorine from human-produced chemicals, and these chlorine levels are still sizable in the Antarctic stratosphere," said NASA atmospheric scientist Paul Newman of NASA's Goddard Space Flight Center, in a statement.
"Natural fluctuations in weather patterns resulted in warmer stratospheric temperatures this year. These temperatures led to a smaller ozone hole."
Scientists first detected a hole in the ozone layer about thirty years ago. A decrease in ozone-depleting substances has led to its regrowth, but officials predict it won't be completely eliminated until 2065 at the earliest.