Science Timeline

  • As early as 1912, Antarctic explorers recorded observations of unusual veil-type clouds in the polar stratosphere, although they could not have known at the time how significant those clouds would become.

    As early as 1912, Antarctic explorers recorded observations of unusual veil-type clouds in the polar stratosphere, although they could not have known at the time how significant those clouds would become.
  • n 1956, the British Antarctic Survey set up the Halley Bay Observatory on Antarctica in preparation for the International Geophysical Year (IGY) of 1957. In that year, ozone measurements using a Dobson Spectrophotometer began.

    n 1956, the British Antarctic Survey set up the Halley Bay Observatory on Antarctica in preparation for the International Geophysical Year (IGY) of 1957. In that year, ozone measurements using a Dobson Spectrophotometer began.
  • Dramatic loss of ozone in the lower stratosphere over Antarctica was first noticed

  • In 1974 two United States chemists predicted that a class of chemicals called chlorofluorocarbons (CFCs), widely used in aerosol spray cans, would seriously damage the ozone layer

  • The British Antarctic Survey's first documentation of the Antarctic ozone hole

  • Folklore has it that when the first measurements were taken

  • In 1985, a group of scientists (J. C. Farman, B. G. Gardiner, and J. D. Shanklin) published in the journal Nature the first paper on observations of springtime losses of ozone over Antarctica

    In 1985, a group of scientists (J. C. Farman, B. G. Gardiner, and J. D. Shanklin) published in the journal Nature the first paper on observations of springtime losses of ozone over Antarctica
  • The first global agreement to restrict CFCs came with the signing of the Montreal Protocol in 1987

    The first global agreement to restrict CFCs came with the signing of the Montreal Protocol in 1987
  • A major European campaign, the European Arctic Stratospheric Ozone Experiment (EASOE) was organised to study the polar regions during the winter of 1991/92

  • In 1994 and 1995 European scientists conducted SESAME, the Second European Stratospheric Arctic and Mid-latitude Experiment.

  • By 1994, the total ozone in October was less than half its value during the 1970s, 20 years previous.

  • The largest ozone hole was founded