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 IX/25: Special Report on Aviation and the Global Atmosphere

The Ninth Meeting of the Parties decided in Dec. IX/25:

  1. To note the statement of the Co-Chairs of the Scientific Assessment Panel that, while the Scientific Assessment of Ozone Depletion will be ready by October 1998, as requested by the Seventh Meeting of the Parties in its decision VII/34, the Special Report on Aviation and the Global Atmosphere being prepared pursuant to the same decision, will not be ready until March 1999;
  2. To approve the date of 31 March 1999 for the submission of the Special Report on Aviation and the Global Atmosphere.