The U.N.'s weather and climate agency said on Thursday there was no cause for alarm about a record-size hole this month in the ozone layer, that shields life on Earth from the sun, as it should shrink again.
The ozone hole that appears over Antarctica fluctuates in size, normally reaching its widest in the polar spring as extreme cold temperatures in the stratosphere and the return of sunlight unleash chlorine radicals that destroy ozone.
Last year, the World Meteorological Organization (WMO) said it detected the first sign of ozone recovery, largely thanks to a 1987 ban on gases that cause ozone depletion, but said it could be a decade before the hole begins shrinking.