Year in review: Ozone hole officially on the mend
Montreal Protocol now covers climate-warming replacements too
A study reported this year confirms that the Antarctic ozone hole is healing. Blue and purple represent areas with the least ozone in this depiction of total ozone from September of this year.
NASA Ozone Watch
In a rare bright spot for global environmental news, atmospheric scientists reported in 2016 that the ozone hole that forms annually over Antarctica is beginning to heal. Their data nail the case that the Montreal Protocol, the international treaty drawn up in 1987 to limit the use of ozone-destroying chemicals, is working.
The Antarctic ozone hole forms every Southern Hemisphere spring, when chemical reactions involving chlorine and bromine break apart the oxygen atoms that make up ozone molecules. Less protective ozone means that more ultraviolet radiation reaches Earth, where it can damage DNA and lead to higher rates of skin cancer, among other threats.
The Montreal Protocol cut back drastically on the manufacture of ozone-destroying compounds such as chlorofluorocarbons
