At a Glance

Each year, the hole reaches its peak in September and begins to shrink after mid-September.This year, the hole grew to 7.6 million square miles.

The hole in the ozone layer over Antarctica is the smallest it's been since 1988, NASA said.

According to apress release, the hole in the Earth's ozone layer thanlast year and 3.3 million square miles smaller than 2015.

Each year, the hole reaches its peak in September and begins to shrink after mid-September.This year, the hole grew to 7.6 million square miles.

NASA and NOAA scientists said warmer temperatures and a stormier upper atmosphere helped keep damaging chemicals chlorine and bromine from eating ozone from the layer that protects theEarth's surface from harmful ultraviolet rays.

“It’s really small this year. That’s a good thing,” Paul Newman,chief Earth scientist at NASA’s Goddard Space Flight Center, told the Associated Press.

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Ozone iscomprised of three oxygen atoms andoccurs naturally in small amounts. In the upper atmosphere,the ozone layer shields the planet from potentially harmful UV raysthat can cause skin cancer, damage crops and contribute to other health issues.

The hole that hovers over Antarctica has been slowly recovering, scientists say, due to an international ban on harmful chemicals that were previously used in refrigerants and aerosols.

The hole was its largest in 2000 and measured 11.5 million square miles.Although recovery is underway, the size of the hole remains large compared to the 1980s, when the hole was first detected, NASA noted.

And while there has been significant healing of the ozone layer in recent years, some scientists say full healing is a slow process and will not occur ,Yale Environment 360 reports.Others expect the Antarctic ozone hole to recover back to 1980 levels around 2070, NASA said.

The treaty,known as the Montreal Protocol, has also helped save millions of lives, in addition to reducing the size of the hole. Several years ago, scientists with the United Nations said an estimated 2 million extra skin cancer cases would have been documented by 2030 without the treaty, the AP reported.