The ozone hole the satellites missed

In May 1985 Joe Farman, Brian Gardiner and Jonathan Shanklin of the British Antarctic Survey reported in Nature that ozone over Halley Bay fell sharply every spring, an anomaly so large they at first suspected their instrument.

1985 CE · -75.58, -26.66 · status: official

The account

They used ground-based Dobson spectrophotometers. NASA scientists then re-examined satellite data and confirmed the hole across the whole continent. Chlorine from CFCs was identified as the cause, leading to the Montreal Protocol of 1987, the most successful environmental treaty to date. Spring ozone losses of up to 70% have since been recorded.

Connections in the atlas

• The great hole in the Weddell Sea ice

Sources

1. Nature: Large losses of total ozone in Antarctica (Farman et al. 1985)
2. Wikipedia: Joe Farman