What date in the 70s, was the Ozone hole detected?
Answers:
It was detected in 1976, but not proven to be caused by humans CFC production until 1985. In 1987 the Montreal protocol was signed by 24 industrialized nations to reduce CFC, Halon, and Halocarbon production. The free chlorine atom in CFC have a life from 20 to 100 years and cause the majority (80%) of damage to the stratospheric ozone. Since 1995 no new CFC have been produced in industrialized countries, the only aerosol to still use CFC in the first world are asthma inhalers and they are being phased out. Only 4.9% of aerosols world wide now have CFC's. Due to the lifespan of CFC moecules it will be some time before we see containment and regeneration of the ozone layer.
The appearance of a hole in the earth's ozone layer over Antarctica, first detected in 1976.
On February 3rd.
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