- The United Nations Secretary-General António Guterres’ message for the International Day for the Preservation of the Ozone Layer, 16 September 2019 - Commemoration of World Ozone Day 2019 - Video address by Inger Andersen, Executive Director, UNEP - World Ozone Day 2019, Letter to National Ozone Officers - Assessment Panels to the Montreal Protocol - A tribute on the occasion of World Ozone Day 2019 - Copernicus Atmosphere Monitoring Service monitors a very unusual 2019 ozone hole