International Day for the Preservation of the Ozone Layer, 16 September

The International Day for the Preservation of the Ozone Layer, commemorates the date of the signing, in 1987, of the Montreal Protocol on Substances that Deplete the Ozone Layer.

“The international community adopted the Montreal Protocol on Substances that Deplete the Ozone Layer to protect the earth from harmful ultraviolet radiation. In more than 24 years of successful implementation, the Protocol has been gradually strengthened to cover the phase-out of nearly 100 ozone-depleting substances. The latest adjustments were adopted in 2007 to accelerate the phase-out of hydrochlorofluorocarbons, or HCFCs,” Secretary-General Ban Ki-moon said in his message for the day.

This year’s theme is “HCFC phase-out: a unique opportunity”. HCFCs (hydrochlorofluorocarbons) are both ozone-depleting substances and powerful greenhouse gases: the most commonly used HCFC is nearly 2,000 times more potent than carbon dioxide in adding to global warming. By agreeing to speed up the phase-out of HCFCs, Parties to the Montreal Protocol increased their already-substantial contributions to protecting the global climate system.

Useful links:

• International Day for the Preservation of the Ozone Layer, website
• United Nations Environment Programme
• Ozon Action Programme of UNEP DTIE
• UNEP, 2011 Ozon Day webpage
• Ozone Secretariat

While the ozone hole has been considered by some as a solved problem, in fact its recovery is still many decades away and the effects and interactions of ozone depletion on climate change are just starting to be understood.

On the 16th September 2011, embark on an investigative journey through the history and science of the ozone layer, the actions taken to address this major environmental threat and the consequences both for the ozone layer and climate system.

This short film seeks out explanations and answers from the scientists closest to the issue.