September 16th is International Day for the Preservation of the Ozone Layer, celebrating the 1987 anniversary of the Montreal Protocol on Substances that Deplete the Ozone Layer. This protocol is the first environmental treaty to achieve universal ratification. The Montreal Protocol’s Kigali amendment, ratified on 1 January 2019, aims at mitigating the future impact on the Earth’s climate of hydrofluorocarbons or HFCs, which are substitutes for ozone depleting substances (ODSs) and powerful greenhouse gases.
The International Ozone Commission was established in 1948 as one of the special commissions of the International Union of Geodesy and Geophysics, who represent the entire community of geophysical scientists around the world. The purpose of the IO3C is to help organize the study of ozone around the world, including ground-based and satellite measurement programs and analyses of the atmospheric chemistry and dynamical processes affecting ozone.