This year's Antarctic ozone hole is the biggest ever, according to US government scientists.
The so-called hole is a region where there is severe depletion of the layer of ozone – a form of oxygen – in the upper atmosphere that protects life on Earth by blocking ultraviolet rays from the sun.
Scientists say human-produced gases, such as bromine and chlorine, damage the layer causing the hole.
"From September 21 to 30, the average area of the ozone hole was the largest ever observed, at 27.4 million square kilometres," said Paul Newman, atmospheric scientist at NASA's Goddard Space Flight Center.
This hole area is larger than the area of North America. "These numbers mean the ozone is virtually gone in this layer of the atmosphere," said David Hofmann, director of the Global Monitoring Division at the National Oceanic and Atmospheric Administration's Earth System Research Laboratory.