Discovery of the Ozone Hole

In 1985, British Antarctic Survey scientists Joe Farman, Brian Gardiner, and Jonathan Shanklin published a paper revealing a dramatic thinning of the ozone layer over Antarctica — a "hole" that had been growing since the late 1970s. The cause was traced to chlorofluorocarbons (CFCs) used in refrigerators, aerosol sprays, and industrial processes. NASA satellite data confirmed the finding. The discovery shocked the world and led to the Montreal Protocol in 1987, in which 197 nations agreed to phase out ozone-depleting substances. It remains the most successful international environmental agreement in history — the ozone layer is now slowly recovering and is expected to fully heal by the 2060s. It proved that collective action on atmospheric threats was possible.