A new research paper recently published (January 4, 2018) in the Geophysical Research Letters “Decline in Antarctic Ozone Depletion and Lower Stratospheric Chlorine Determined From Aura Microwave Limb Sounder Observations” highlights that inorganic chlorine is the catalyst in destroying ozone in the upper atmosphere, the stratosphere. While this was often assumed, this is Paper is seen as providing the first direct proof that the ozone hole is recovering due to less chlorine (chemicals) in the stratosphere.
It is still believed the ozone hole and depletion in the broader context will still take until the years 2060-2080 before the ozone layer recovers itself naturally. See the full Paper at: http://onlinelibrary.wiley.com/doi/10.1002/2017GL074830/full
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