-
CFCs Invented
“Wonder gas” CFCs were invented in 1928
for commercial applications. -
Scientists Discover CFCs Split Up Ozone in Atmosphere
In late 1973, Rowland and Molina, who had recently joined Rowland’s lab, used data from a variety of published sources to calculate that CFC molecules released near the surface of Earth would, over decades, wind up in the stratosphere where UV radiation would split off chlorine atoms. Each chlorine atom would react immediately with an ozone molecule, setting off a chain reaction that would destroy thousands of ozone molecules. -
UN Gets Involved
In 1977, the United Nations Environment Programme (UNEP)
sets up a co-ordinating committee to study the ozone layer. -
Countries Begin to Ban Some CFCs
In 1978, the United States of America, Canada,
Sweden and Norway ban the use of CFCs in aerosols. -
UNEP Starts Inter-Governmental Negotiations
In 1981, UNEP starts inter-governmental negotiations
to protect the ozone layer. -
Vienna Convention for the Protection of the Ozone Layer
Governments agree to study, exchange information and
protect the ozone layer - through the Vienna Convention for the
Protection of the Ozone Layer (1985). Scientists continue to find proof of ozone depletion. -
Evidence Found
The British Antarctic Team discovers severe thinning in the ozone layer over Antarctica - the ozone hole.
