Ozone hole comparison over Antarctica measured in 2006 and 2007 by Envisat. The ozone loss in 2007 peaked at 27.3 million tons, compared to the 2006 record ozone loss of 39.4 million tons.
The ozone hole over Antarctica shrank by 30 percent this year compared with last year’s record loss, according to a report by the European Space Agency.
Measurements made by the agency’s Envisat satellite show this year’s ozone loss peaked at 27.3 million tons, compared to the 2006 record loss of 39.4 million tons.
The hole in Earth’s protective stratospheric ozone layer goes through a cycle each year as the chemical reactions that cause the depletion peak during the deep chill of the southern hemisphere winter.
The layer has been badly damaged for decades by the use of man-made chlorine-based chemicals.
Scientists say this year’s smaller hole is due to natural variations in temperature and atmospheric dynamics and is not indicative of a long-term trend due to the reduced use of ozone-depleting chemicals.
Animation: European Space Agency