This year, the US’s National Aeronautics and Space Administration (NASA) satellite observations determined the ozone hole reached a maximum of 24.8 million square kilometres, roughly the size of North America, before beginning to shrink in mid-October. The hole was attributed to chemically active forms of chlorine and bromine, derived from human-produced compounds and released into the stratosphere.
Southern hemispheric country like New Zealand usually has to issue ultraviolet warning in summer due to ozone holes.
Source: VOV5