Ozone Layer By MaryAnnC15 Aug 21, 1890 Ozone first identified and studied Jan 1, 1920 British scientist began measuring the amoount of ozone in the atmosphere Aug 21, 1935 More ozone thinning New refrigirators in U.S, use of more plastic foams, solvents , and propellants in spray cans. Polution destroying the oxygen molecules Aug 29, 1950 CFC market expands rapidly late 1950's Aug 21, 1970 Scientists began to detect the presence of CFCs in the atmosphere CFC= Chloroflourocarbon Jun 21, 1981 British Antarctic Survey was monitoring the atmosphere above Antarctica Mar 29, 1985 Vienna Convention for the Protection of the Ozone Layer Aug 22, 1985 Ozone hole over Antarctica Oct 21, 1985 They reported a confirmed decrease in the amount of ozone in the stratomsphere Jun 1, 1987 Montreal Protocol, to reduce CFC in the ozone Aug 22, 1994 By 1994, the total ozone in October was less than half its value during the 1970s Apr 1, 2006 the ozone hole over Antarctica was arguably the largest on record, with average ozone levels over Antarctica the thinnest ever observed. Aug 22, 2006 Biggest ozone hole reportted