Record hole in ozone layer 'no cause for alarm'

UN weather and climate agency says hole over Antarctica is larger due to colder stratosphere but will shrink again

The UN'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 which 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.