ATMOSPHERE × TECHNOLOGY

The Hole We Closed

1985 to 2016 CE

Phanerozoic · Cenozoic · Quaternary · Holocene · Meghalayan

Refrigerant gases were destroying the ozone that keeps ultraviolet off the surface, and every southern spring a hole opened over Antarctica. It was found from the ground, by people whose readings were so far outside expectation that the satellites had been discarding the same numbers as errors. The gases were banned worldwide within two years, and in 2016 the healing was measured.

Why it matters

This is the one time our species noticed it was breaking a planetary system, agreed to stop, and could afterwards prove the repair. It took three decades between the ban and the proof, which is the honest measure of how slowly a planet answers, and it is the precedent every argument about carbon has to reckon with.

Dating & uncertainty

The hole was reported in 1985, from measurements so far outside expectations that satellite data had been discarding them as errors. The treaty followed in 1987, and the first statistically significant healing was published in 2016.

Sources

1. Farman, Gardiner & Shanklin (1985), Nature · Large losses of total ozone in Antarctica reveal seasonal ClOx/NOx interaction
2. Solomon et al. (2016), Science · Emergence of healing in the Antarctic ozone layer
3. Cooke et al. (2022), Royal Society Open Science · A revised lower estimate of ozone columns during Earth's oxygenated history

Earth history as one day

23:59:59.9992780 µs before midnight

if Earth’s 4.54 billion years were compressed into a single day