Emissions of one of the chemicals most responsible for the Antarctic ozone hole are on the rise, despite an international treaty that required an end to its production in 2010, a new NOAA study shows.
The 2015 Antarctic ozone hole area was larger and formed later than in recent years, according to scientists from NOAA and NASA.
On Oct. 2, 2015, the ozone hole expanded to its peak of 28.2 million square kilometers (10.9 million square miles), an area larger than the continent of North America. Throughout October, the hole remained large and set many area daily records.
The Antarctic ozone hole, which forms annually in the August to October period, reached its peak size on September 11, stretching to 9.3 million square miles (24.1 million square kilometers), roughly the same size as last year’s peak of 9.3 million square miles (24 million square kilometers) on September 16, 2013. This is an area similar in size to North America.
Scientists have found a large reduction in the amount of the coldest deep ocean water, called Antarctic Bottom Water, all around the Southern Ocean using data collected from 1980 to 2011.