For the purposes of this Protocol: 1. "Convention" means the Vienna Convention for the Protection of the.This document should be cited as: World Meteorological Organization (WMO). Scientific Assessment of Ozone Depletion: 2022, GAW Report No. 278,. In 1987, 56 countries agreed under what became known as the Montreal Protocol to cut CFC production and use in half. This cooperation resulted in the signing of the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987. Negotiations have now begun on a Protocol to the Vienna. Convention for the Protection of the ozone Layer.