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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.


The ocean is a reservoir for CFC-11, a major ozone-depleting chemical. Anthropogenic production of CFC-11 dramatically decreased in the 1990s under the Montreal Protocol, which stipulated a global phase out of production by 2010. However, studies raise questions about current overall emission levels and indicate unexpected increases of CFC-11 emissions of about 10 Gg · yr−1 after 2013 (based upon measured atmospheric concentrations and an assumed atmospheric lifetime).

Decline in emissions of CFC-11 in China

Emissions of ozone-depleting substances, including trichlorofluoromethane (CFC11), have decreased since the mid-1980s in response to the Montreal Protocol1,2. In recent years, an unexpected increase in CFC-11 emissions beginning in 2013 has been reported, with much of the global rise attributed to emissions from eastern China3,4. Here we use high-frequency atmospheric mole fraction observations from Gosan, South Korea and Hateruma, Japan, together with atmospheric chemical transport-model simulations, to investigate regional CFC-11 emissions from eastern China.

Scientific articles
Decline in emissions of CFC-11 in 2018-2019

The atmospheric concentration of trichlorofluoromethane (CFC-11) has been in decline since the production of ozone-depleting substances was phased out under the Montreal Protocol1,2. Since 2013, the concentration decline of CFC-11 slowed unexpectedly owing to increasing emissions, probably from unreported production, which, if sustained, would delay the recovery of the stratospheric ozone layer1–12. Here we report an accelerated decline in the global mean CFC-11 concentration during 2019 and 2020, derived from atmospheric concentration measurements at remote sites around the world.

Unexpected nascent atmospheric emissions of three ozone-depleting hydrochlorofluorocarbons

Global and regional atmospheric measurements and modeling can play key roles in discovering and quantifying unexpected nascent emissions of environmentally important substances. We focus here on three hydrochlorofluorocarbons (HCFCs) that are restricted by the Montreal Protocol because of their roles in stratospheric ozone depletion. Based on measurements of archived air samples and on in situ measurements at stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, we report global abundances, trends, and regional enhancements for HCFC-132b (CH2ClCClF2), which is newly discovered in the atmosphere, and updated results for HCFC-133a (CH2ClCF3) and HCFC-31 (CH2ClF). 

Mass Communication Repository

Ref:  UNEP/EO/Ozone Staff                                                                                                                    30 September 2020

Dear Parties to the Vienna Convention and the Montreal Protocol,

With reference to Ms. Tina Birmpili’s departure from the position of Executive Secretary of Ozone Secretariat at the end of this month, I wish to take this opportunity to inform you that Ms. Meg Seki, currently Deputy Executive Secretary, has been designated as Acting Executive Secretary, effective 1 October.

As you may be aware, Ms. Seki, a national of Japan, has had a longstanding involvement on ozone layer issues, having joined as one of the first staff members in the Secretariat when it was formally established in 1989. She has had notable experience, working on the establishment of ozone country programmes, the regional ozone networks, global environmental assessments, climate change issues, transboundary air pollution, among others. She rejoined the Ozone Secretariat in 2003 and is currently the Deputy Executive Secretary. I remain confident that Ms. Seki in her acting capacity will very ably steer the Secretariat, as was done by Ms. Birmpili at its helm.

I would also like to inform you that a competitive recruitment process has been launched for the selection of a new Executive Secretary at the D2 level. The job opening was launched on 14 September 2020 and will be open to receive applications until 28 October 2020.

And finally, my deepest thanks and appreciation to Tina for her outstanding leadership in achieving formidable milestones for the Secretariat over the years.

Yours sincerely,

Inger Andersen

Executive Director

Parties’ reports on illegal trade, Tools