Scientist who beat Nasa to the ozone hole: Joe Farman, physicist and environmental hero, 1930-2013

May 17, 2013 7:11 pm

Scientist who beat Nasa to the ozone hole

By Pilita Clark

Joe Farman was not long out of university when he nearly turned his back on the job that led him to make one of the most important discoveries in environmental science.

The young Cambridge physicist had spotted an advert in New Scientist magazine for a researcher to go to Antarctica. “I sort of blinked at it,” he later said, before eventually deciding: “Well if I don’t do it now I won’t ever do it.” That he applied was just as well. Farman, who has died aged 82, became the man who found the hole in the world’s ozone layer. Even so, it was not something that happened in the most straightforward way. By 1956 he had begun a life with what is now theBritish Antarctic Survey in Cambridge. “They were just doing curiosity-based research,” says Chris Rapley, a former BAS director. This included measuring the ozone in the stratosphere – the bluish-green gas that filters out ultraviolet solar rays, which hasten skin cancers, cataracts and other ills.But skin cancer was not a chief concern at the time. Rather, it was thought ozone readings might help to improve weather forecasts. The life of Joseph Charles Farman, a builder’s son from Norwich born on August 7 1930, proceeded quietly.

By his 52nd birthday Farman was heading towards the end of a career marked by a dogged pursuit of data rather than stellar bursts of academic fame, with just a handful of published papers to his name. He lived in Cambridge with his wife Paula, who survives him; he liked bridge and the music of Hector Berlioz and had a fondness for smoking his pipe so fiercely that colleagues would brace themselves for a visit to his fume-filled office.

Yet in 1982 he noticed the ageing instrument the BAS was using to measure the thickness of the ozone layer was sending back some odd results. The Dobsonmeter was a white contraption the size of a small coffin that came with an instruction manual advising users to wrap it in a quilt to keep it warm. It was a humble beast compared with the Nasa satellites that orbited above it. They were beaming down thousands of measurements a day. The Dobsonmeter produced five to 15 daily readings, which were sent back by ship and typed up by a pool of women for Farman’s small team of researchers to pick through. All the same, it seemed to have picked up something Nasa had missed: a mysterious dip in ozone levels.

A few scientists had feared this might happen because of the growing use of synthetic chemicals known as chlorofluorocarbons in hairsprays and other aerosol products. But scientific evidence was thin. Antarctic ozone was thought to be so well understood that officials at the UK’s state-funded Natural Environment Research Council were thinking of ending the survey’s monitoring of the gas, says Jonathan Shanklin, who worked under Farman at the BAS. So when he and Farman saw the Dobsonmeter data, they were nervous. “We would have looked complete fools if we had published something on the basis of a faulty instrument or just bad maths,” he told the Financial Times. “That would have been the end of the programme, full stop.”

By 1984, despite the arrival of a new Dobsonmeter, the ozone hole seemed to have grown to even more alarming proportions. The following year Farman, Mr Shanklin and another colleague published their results in Nature, the science journal. It caused a sensation. As Farman later said, though, the conclusions were so obvious that if he had shown the data to his grandmother she would have been able to “see what I’m talking about”.

Nasa’s satellites, it turned out, had recorded the same falling ozone levels – but the agency’s computer software had deemed the readings unreliable. Perhaps more pertinently, Nasa had been taking ozone measurements for only a few years. Farman and his team had been doing that for more than a quarter-century, making them more sensitive to the rapid changes they were seeing.

Pressure began to build for action against CFCs, though not everyone was convinced. Donald Hodel, Ronald Reagan’s interior secretary, was widely reported to have rejected any need for regulation, saying a campaign to encourage people to slap on more sun lotion and wear sunglasses should do the trick. He later denied making such a claim.

But after Nasa sent a research aircraft through the ozone hole and confirmed Farman’s findings, politicians began to act. By 1987 the Montreal Protocol to limit ozone-depleting chemicals had been agreed and by 1989 it was in force. The hole is on the mend.

Environmental activists often cite Montreal as an example of how to address climate change. Farman was never that optimistic. This was a “pious hope”, he said not long ago. “You can’t really claim that we taught the politicians or powers anything at all.”