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The Vienna Convention for the Protection of the Ozone Layer and the Montreal Protocol on Substances that Deplete the Ozone Layer logo was developed to provide a distinct brand for the two treaties across various communication assets and applications. The visual identity guideline is designed to provide a comprehensive overview of applications and correct use of the logo.

Briefing notes
Baselines:  Past practices and current challenges

The purpose of this briefing note is to provide background information about the following areas:

  • The baselines agreed under the Montreal Protocol to date for CFCs, carbon tetrachloride, HCFCs and methyl bromide, as examples, in both non-Article 5 and Article 5 parties;
  • The time lag between the year in which a decision was taken and the years of the baseline and initial control measures;
  • The baselines that have been put forward in the HFC amendment proposals.

2015 meeting, parties decided “Dubai pathway on HFCs” to “work within the Montreal Protocol to an HFC amendment in 2016 by resolving challenges by generating solutions in the contact group on the feasibility and ways of managing HFCs”. This briefing note is to provide background info about agreed baselines under Montreal Protocol, time lag between decision and the years of baseline and initial controls, and baselines put forward in the HFC amendment proposals. The information in this note is intended only as background material for the parties; it is not intended to be exhaustive and does not provide policy recommendations.

Funding and flexibility in implementation: Issues raised during informal consultations among parties

This briefing note focuses on the key issues related to funding and flexibility in implementation that were discussed by the contact group at the 37th OEWG in Geneva.3 It presents background information related to a number of outstanding issues to be discussed further when the 37th Meeting of the Open-Ended Working Group resumes its work. The issues discussed in this note have been identified in informal discussions during the 37th Meeting of the Open-ended Working Group (OEWG) and were presented by the co-chairs of the contact group. This section is divided into those issues relevant to incremental costs in the consumption, production, and servicing sectors, and also addresses a number of cross-cutting issues.

Scientific articles
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Industrial chlorofluorocarbons that cause ozone depletion have been phased out under the Montreal Protocol. A chemically-driven increase in polar ozone (or “healing”) is expected in response to this historic agreement. Observations and model calculations taken together indicate that the onset of healing of Antarctic ozone loss has now emerged in September. Fingerprints of September healing since 2000 are identified through (i) increases in ozone column amounts, (ii) changes in the vertical profile of ozone concentration, and (iii) decreases in the areal extent of the ozone hole. Along with chemistry, dynamical and temperature changes contribute to the healing, but could represent feedbacks to chemistry. Volcanic eruptions episodically interfere with healing, particularly during 2015 (when a record October ozone hole occurred following the Calbuco eruption).