Posts Tagged ‘nasa’

Joe Farman (left), with Brian Gardiner and Jon Shanklin, discovers of the depletion of the ozone layer

Joe Farman (left), with Brian Gardiner and Jon Shanklin, discovers of the depletion of the ozone layer

Joe Farman died in Cambridge on 11 May 2013. His name is unknown to most people. He was a British physicist who along with fellow researchers, Brian Gardiner and Jon Shanklin, caused a sensation when they published their findings in Nature in May 1985 revealing that the levels of ozone above the Antarctic had fallen by about 40% between 1975 and 1984. This had caused a very large hole  (more correctly a reduction in the concentration of ozone) to appear in the ozone layer, a thin layer in the earth’s stratosphere which absorbs virtually all the ultraviolet rays from the sun which are harmful to life.

The hypothesis of ozone depletion had been put forward in the 1970s but had been dismissed by NASA scientists after satellites failed to substantiate the loss. Since 1957, Farman and his colleagues had been looking at atmospheric data collected by the British Antarctic Survey station at Halley Bay, Antarctica, using old-fashioned devices like weather balloons and a Dobson meter, a rudimentary ozone measuring machine that had to be wrapped in a duvet to work properly. At first the figures were questioned, even by the team. Perhaps the discrepancy was just above Halley Bay? Measurements were taken 1,000 miles further north, but these showed the same result? Why had NASA’s satellites not picked up the anomaly. Much later and to NASA’s embarrassment, the data had been collected by the satellites but had been overlooked.

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