The ozone layer protects the earth from harmful ultra violet radiation entering its surface, exposure to which causes skin cancer in people. This protective layer is now in danger of depletion as a result of the many manmade chemicals which are released to the stratosphere every year. Although international intervention has seen a rapid decline in the production and emission of ozone destroying chemicals, they have already caused damage and the remaining chemicals continue to cause further damage.
50% -90% of the ozone layer over the Antarctic gets destroyed during the months of September to November as a result of a chemical reaction in the atmosphere. This decrease in the ozone layer is known as the “ozone hole”.
NASA and the National Oceanic and Atmospheric Administration (NOAA) use balloon-borne instruments and satellites to monitor the annual Antarctic ozone hole. They also monitor global levels of ozone in the stratosphere and the manmade chemicals that contribute to ozone depletion.
It has been revealed that this year has seen the ninth biggest ozone hole in recorded history stretching over 10.5 million square miles. The ozone hole usually begins to close by December when warmer weather comes in.