Protecting the ozone layer: Vienna Convention and Montreal Protocol

Vienna Convention for the Protection of the Ozone Layer

In 1981, UNEP acted on a proposal to develop a global convention on the ozone layer. The draft convention was first presented to the international community that year. A lack of understanding about the true extent of the environmental risks from ozone depletion made early negotiations very difficult. There were also questions about the validity of the science, and doubts about the technology to respond to the challenge. Perseverance, however, resulted in the 1985 Vienna Convention on the Protection of the Ozone Layer, a multilateral environmental agreement. On June 4, 1986, Canada was the first nation to ratify the treaty, which entered into force in 1988.

Countries could not agree on specific control measures, making the Vienna Convention a framework treaty for controls development that also facilitated cooperation on research. This called for international monitoring and scientific assessment. However, it does not include legally binding reduction goals. These are laid out in the accompanying Montreal Protocol on Substances that Deplete the Ozone Layer.

Whereas in the last century, the term convention was regularly employed for bilateral agreements, it is now generally used for formal multilateral treaties with a broad number of parties. A protocol, in the context of treaty law and practice, has the same legal characteristics as a treaty. The term protocol is often used to describe agreements of a less formal nature than those entitled treaty or convention. Generally, a protocol amends, supplements or clarifies a multilateral treaty. A protocol is normally open to participation by the parties to the parent agreement.

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Montreal Protocol on Substances that Deplete the Ozone Layer

In the two years that followed the creation of the Vienna Convention there was incredible progress in reaching a global scientific consensus on the nature of the threat from ozone loss. Agreement was also reached on other outstanding scientific and technological matters. By September 1987, the disagreements and lack of understanding had given way to substantial trust among the international community. And so it was on September 16, 1987, that the Montreal Protocol on Substances that Deplete the Ozone Layer was negotiated and signed by Canada along with 23 other countries. As of September 16, 2009, it has been signed and ratified by 196 countries, achieving universal participation.

Under the Montreal Protocol, 95% of the production and consumption of all ozone-depleting substances have been phased-out. Global observation have verified that atmospheric levels of key ozone-depleting substances are going down and it is believed that with implementation of the Montreal Protocol's provisions, the ozone layer should return to its pre-1980 levels by 2050 to 2075.

Main goal

The most significant commitments in the Montreal Protocol are the schedules for phasing out ozone-depleting substances (ODSs). They are subject to what’s called essential and critical use provisions - a party is permitted to produce and consume a given ODS if specific stringent criteria are met. There are different phase-out schedules for developed and developing countries. Depending on the substance, developing countries have 10-15 additional years to meet phase-out targets. There are essential and critical use exemption provisions in which a Party is permitted to produce and consume a given ODS if specific stringent criteria are met.

Features of the Montreal Protocol

The Montreal Protocol features eight key elements:

  1. It requires all Parties to eliminate the production and import of nearly 100 substances that deplete the ozone layer, in accordance with agreed timelines.
  2. It includes special provisions for developing countries. These countries are given a 10 to 15 year grace period beyond the agreed dates to completely phase out a substance.
  3. It includes a Multilateral Fund which is a financial mechanism to help qualifying developing countries to phase out their consumption of ozone-depleting substances. Canada contributes to the administration of the Multilateral Fund through contributions to the Fund, its bilateral program and by hosting the Fund secretariat in Montreal.
  4. It requires Parties to report annually on the production, import and export of each of the controlled ozone-depleting substances.
  5. It established an Implementation Committee to review the reports on production and consumption of ozone-depleting substances. This committee assesses the compliance status of countries and makes recommendations to the decisional body of the Protocol, the Meeting of the Parties, regarding Parties in non-compliance.
  6. It precludes Parties from trading ozone-depleting substances with non-parties.
  7. It requires regular assessments to enable Parties to make informed decisions with the most up-to-date information on science, environmental effects, technology and economics.
  8. It has flexibility designed into it to allow for its further development. It includes an adjustment provision to accelerate the phase-out of ozone-depleting substances without going through the lengthy formal process of national ratification. It also includes an amendment provision to facilitate the addition of new chemicals.

Substances covered by the Montreal Protocol

The Montreal Protocol controls nearly 100 chemicals that are grouped in the following categories:

  • Chlorofluorocarbons (CFCs)
  • Halons
  • Carbon tetrachloride (CTC)
  • Hydrochlorofluorocarbons (HCFC)
  • Methyl chloroform
  • Methyl bromide

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