The Montreal Protocol on Substances that Deplete the Ozone Layer

The Montreal Protocol on Substances that Deplete the Ozone Layer is a global agreement to protect the Earth’s ozone layer by phasing out the chemicals that deplete it. This phase-out plan includes both the production and consumption of ozone-depleting substances. The landmark agreement was signed in 1987 and entered into force in 1989.

The parties to the Protocol meet once a year to make decisions aimed at ensuring the successful implementation of the agreement. These include adjusting or amending the Protocol, which has been done six times since its creation. The most recent amendment, the Kigali Amendment, called for the phase-down of hydrofluorocarbons (HFCs) in 2016. These HFCs were used as replacements for a batch of ozone-depleting substances eliminated by the original Montreal Protocol. Although they do not deplete the ozone layer, they are known to be powerful greenhouse gases and, thus, contributors to climate change.

The Montreal Protocol provided a set of practical, actionable tasks that were universally agreed on. The Protocol has successfully met its objectives thus far and continues to safeguard the ozone layer today. Thanks to the collaborative effort of nations around the world, the ozone layer is well on its way to recovery.

Decision IV/13: Assessment panels

The Fourth Meeting of the Parties decided in Dec. IV/13:

  1. to note with appreciation the work done by the Panels for Ozone Scientific Assessment, Environmental Effects Assessment, and Technology and Economic Assessment in their reports of November-December 1991;
  2. to request the Technology and Economic Assessment Panel and its Technical and Economic Options Committees to report annually to the Open-ended Working Group of the Parties to the Montreal Protocol the technical progress in reducing the use and emissions of controlled substances and assess the use of alternatives, particularly their direct and indirect global-warming effects;
  3. to request the three assessment panels to update their reports and submit them to the Secretariat by 30 November 1994 for consideration by the Open-ended Working Group and by the Seventh Meeting of the Parties to the Montreal Protocol. These assessments should cover all major facets discussed in the 1991 assessments with enhanced emphasis on methyl bromide. The scientific assessment should also include an evaluation of the impact of sub-sonic aircraft on ozone;
  4. to encourage the panels to meet once a year to enable the co-chairpersons of the panels to bring to the notice of the meetings of the Parties to the Montreal Protocol, through the Secretariat, any significant developments which, in their opinion, deserve such notice.