Antarctic ozone hole measures seventh smallest size in decades

The ozone hole over the Antarctic could fully mend by 2066, according to the National Oceanic and Atmospheric Administration (NOAA).

The hole, which opens annually over Earth’s southern pole, was relatively small this year. It ranked the seventh smallest on record since recovery efforts began in 1992.

Smaller doesn’t small, however. At almost 8 million square miles, the monthly average ozone-depleted region in the Antarctic this year was nearly three times the size of the contiguous U.S., the NOAA said in a news release.

The recent improvement is the result of declining chlorofluorocarbons (CFCs), a chemical that’s harmful to the ozone and was phased out by the Montreal Protocol. The measure was signed in 1987 to phase out CFC-based products and processes by 2010.

An unexpected infusion of ozone carried by air currents from north of the Antarctic also contributed to the hole’s repairs, scientists said.

"The gradual improvement we’ve seen in the past two decades shows that international efforts that curbed ozone-destroying chemicals are working,” said Paul Newman, leader of NASA’s ozone research team and chief scientist for Earth sciences at NASA’s Goddard Space Flight Center in Greenbelt, Md.