The Antarctic ozone hole is discovered

In May 1985 Joseph Farman, Brian Gardiner and Jonathan Shanklin of the British Antarctic Survey published data showing that the springtime ozone over Halley Station in Antarctica had dropped by about 40 per cent since the 1970s. NASA satellite data, which had been discarded as errors by computer software, soon confirmed the deficit. The cause was chlorofluorocarbons (CFCs) from refrigerants and aerosols, whose chlorine destroys ozone on the surface of polar stratospheric clouds. The discovery led within two years to the Montreal Protocol.

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