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The axe was poised over the British Antarctic Survey’s ozone monitoring programme when it noticed an awfully big hole in the sky

THE great Ernest Rutherford once remarked that all science is either physics or stamp collecting. While physicists are seekers of the truth who uncover sweeping laws of nature, the rest are mere collectors, who pigeonhole things into categories. But the story of the hole shows that collecting and categorising can have a huge impact.

In the early 1980s, when British research faced government cutbacks, long-term monitoring programmes were under threat. Among them were the measurements of atmospheric ozone at the UK’s Halley research station in Antarctica.

The British Antarctic Survey (BAS) was looking at ways to economise, and axing ozone monitoring seemed unlikely to be a big loss. Then, in May 1985, came a bombshell: Joe Farman, Brian Gardiner and Jonathan Shanklin (Nature, vol 315, p 207). The BAS researchers were still using a 25-year-old instrument to assess the thickness of the ozone layer by measuring ultraviolet radiation penetrating the atmosphere. Until then there had only been anecdotal reports of low values, but a trend was vividly revealed when the team plotted averages of minimum measurements. Farman then worked out some of the chemistry of the hole.

While the Brits were using their old-fashioned instrument, NASA’s Nimbus 7 satellite also produced clear evidence of depletion. But so overwhelming was the flood of data and so unprepared were the Americans for unusually low measurements that, , it was initially overlooked.

Farman’s unexpected discovery showed for all to see how human activity can harm the atmosphere – in this case with the chemicals used in refrigeration, air conditioning and solvents. Governments agreed on action and today ozone levels are (Nature, vol 465, p 34). Not a bad outcome for a boring philately project.

Read more: Zeros to heroes: 10 unlikely ideas that changed the world