Editing Montreal Protocol (section)

{{Short description|1987 treaty to protect the ozone layer}}
{{Update|date=February 2025}}
{{Use dmy dates|date=January 2022}}
{{Infobox Treaty
| name                = Montreal Protocol
| long_name           = The Montreal Protocol on Substances That Deplete the Ozone Layer
| date_signed         = 16 September 1987<ref>{{cite web|url=https://www.unep.org/ozonaction/who-we-are/about-montreal-protocol|title=About Montreal Protocol|website=[[United Nations Environment Programme]]|date=29 October 2018 |access-date=10 October 2024}}</ref>
| location_signed     = [[Montreal]]
| date_sealed         =
| date_effective      = 1 January 1989 if 11 states have ratified by then. 
| condition_effective = Ratification by 20 states
| date_expiration     =
| signatories         = 46
| ratifiers           = 198 (all United Nations members, as well as the [[Cook Islands]], [[Niue]], the [[Holy See]], [[Palestine]], and the [[European Union]])
| depositor           =[[Secretary-General of the United Nations]]
| languages           =Arabic, Chinese, English, French, Russian, and Spanish.
| website             = 
| wikisource          =
}}
[[File:NASA and NOAA Announce Ozone Hole is a Double Record Breaker.png|thumb|right|The largest Antarctic ozone hole recorded (September 1985)]]
[[File:Retrospective video on the Montreal Protocol.ogv|thumb|300px|2012 retrospective video by NASA on the Montreal Protocol]]

The '''Montreal Protocol on Substances That Deplete the Ozone Layer'''<ref name="UIA">{{Cite web |url=https://uia.org/s/or/en/1100031640 |url-access= |title=Montreal Protocol on Substances that Deplete the Ozone Layer |author1=Staff writer |year=2024 |department=UIA Global Civil Society Database |website=uia.org |publisher=[[Union of International Associations]] |agency=Yearbook of International Organizations Online |location=Brussels, Belgium |format= |arxiv= |asin= |bibcode= |doi= |isbn= |issn= |jfm= |jstor= |lccn= |mr= |oclc= |ol= |osti= |pmc= |pmid= |rfc= |ssrn= |zbl= |id= |access-date=17 January 2025 |url-status= |archive-url= |archive-date= |via= |quote= |trans-quote= }}</ref> is an international [[treaty]] designed to protect the [[ozone layer]] by phasing out the production of numerous substances that are responsible for [[ozone depletion]]. It was agreed on 16 September 1987, and entered into force on 1 January 1989. Since then, it has undergone several amendments and adjustments, with revisions agreed to in 1990 ([[London]]), 1992 ([[Copenhagen]]), 1995 ([[Vienna]]), 1997 ([[Montreal]]), 1999 ([[Beijing]]), 2007 (Montreal), 2016 ([[Kigali]]) and 2018 ([[Quito]]).<ref>{{Cite web|url=https://sdg.iisd.org:443/news/kigali-amendment-enters-into-force-bringing-promise-of-reduced-global-warming/|title=Kigali Amendment Enters into Force, Bringing Promise of Reduced Global Warming {{!}} News {{!}} SDG Knowledge Hub {{!}} IISD|last=Hub|first=IISD's SDG Knowledge|language=en-US|access-date=2019-03-07}}</ref><ref>{{Cite web|url=https://www.bbc.com/news/science-environment-37665529|title=Deal reached on HFC greenhouse gases|first=Matt|last=McGrath|date=15 October 2016|publisher=BBC}}</ref><ref>{{cite web |url=https://ozone.unep.org/treaties/montreal-protocol-substances-deplete-ozone-layer/the-evolution-of-the-montreal-protocol|title=The Evolution of the Montreal Protocol|publisher=United Nations Environment Programme Ozone Secretariat |access-date=2 November 2024 |archive-url=https://web.archive.org/web/20240822180439/https://ozone.unep.org/treaties/montreal-protocol-substances-deplete-ozone-layer/the-evolution-of-the-montreal-protocol |archive-date=22 August 2024 |url-status=live }}</ref> As a result of the international agreement, the ozone hole over [[Antarctica]] is slowly recovering.<ref>Ewenfeldt B, "Ozonlagret mår bättre", ''[[Arbetarbladet]] 12-9-2014, p. 10.''</ref> Climate projections indicate that the ozone layer will return to 1980 levels between 2040 (across much of the world) and 2066 (over Antarctica).<ref>{{cite news|title=Ozone Layer on Track to Recovery: Success Story Should Encourage Action on Climate|url=http://www.unep.org/newscentre/Default.aspx?DocumentID=2796&ArticleID=10978&l=en|access-date=18 September 2014|agency=UNEP|publisher=UNEP|date=10 September 2014|archive-date=13 September 2014|archive-url=https://web.archive.org/web/20140913031932/http://www.unep.org/newscentre/default.aspx?DocumentID=2796&ArticleID=10978&l=en|url-status=dead}}</ref><ref>{{cite journal|author1=Susan Solomon|author2=Anne R. Douglass|author3=Paul A. Newman|title=The Antarctic ozone hole: An update|journal=Physics Today|volume=67|issue=7|pages=42–48|date=July 2014|doi=10.1063/PT.3.2449|bibcode=2014PhT....67g..42D |doi-access=free|hdl=1721.1/99159|hdl-access=free}}</ref><ref>{{Cite web|url=https://www.canada.ca/en/environment-climate-change/corporate/international-affairs/partnerships-organizations/ozone-layer-depletion-montreal-convention.html|title=Ozone layer depletion: Montreal Protocol|last=Canada|first=Environment and Climate Change|date=2015-02-20|website=aem|access-date=2020-04-22}}</ref><ref>{{Cite journal |last=World Meteorological Organization (WMO) |date=2022 |title=Scientific Assessment of Ozone Depletion: 2022 |url=https://ozone.unep.org/system/files/documents/Scientific-Assessment-of-Ozone-Depletion-2022-Executive-Summary.pdf |journal=[[GAW Report]] |publisher=WMO |publication-place=Geneva |issue=278 |pages=i}}</ref> Due to its widespread adoption and implementation, it has been hailed as an example of successful international co-operation. Former [[United Nations]] (UN) Secretary-General [[Kofi Annan]] stated that "perhaps the single most successful international agreement to date has been the Montreal Protocol".<ref>{{cite web |url=http://www.theozonehole.com/montreal.htm |title=The Ozone Hole – The Montreal Protocol on Substances that Deplete the Ozone Layer |publisher=Theozonehole.com |date=16 September 1987 |access-date=17 August 2007 |archive-date=12 September 2012 |archive-url=https://archive.today/20120912223944/http://www.theozonehole.com/montreal.htm |url-status=dead }}</ref><ref>{{Cite web|url=https://www.un.org/en/events/ozoneday/background.shtml|title=Background for International Day for the Preservation of the Ozone Layer – 16 September|website=un.org|language=EN|access-date=2017-05-28}}</ref> In comparison, effective burden-sharing and solution proposals mitigating regional conflicts of interest have been among the success factors for the ozone depletion challenge, where global regulation based on the [[Kyoto Protocol]] has failed to do so.<ref name=cass>[http://law.vanderbilt.edu/files/archive/Sunstein-2008.pdf Of Montreal and Kyoto: A Tale of Two Protocols] {{Webarchive|url=https://web.archive.org/web/20140826120056/http://law.vanderbilt.edu/files/archive/Sunstein-2008.pdf |date=26 August 2014 }} by Cass R. Sunstein 38 ELR 10566 8/2008</ref> In this case of the ozone depletion challenge, there was global regulation already being installed before a scientific consensus was established. Also, overall public opinion was convinced of possible imminent risks.<ref name="par">[https://www.researchgate.net/publication/41184037_Climate_Change_and_Knowledge_Politics Environmental Politics Climate Change and Knowledge Politics] {{webarchive|url=https://web.archive.org/web/20140826115142/http://stsclimate.soc.ku.dk/papers/grundmannclimatechangeandknowledgepolitics.pdf|date=26 August 2014}} [[Reiner Grundmann]], Vol. 16, No. 3, 414–432, June 2007</ref><ref name = RG>[http://www.mpifg.de/pu/mpifg_book/mpifg_bd_39.pdf Technische Problemlösung, Verhandeln und umfassende Problemlösung, (eng. technical trouble shooting, negotiating and generic problem solving capability)] {{Webarchive|url=https://web.archive.org/web/20160303233113/http://www.mpifg.de/pu/mpifg_book/mpifg_bd_39.pdf |date=3 March 2016 }} in Gesellschaftliche Komplexität und kollektive Handlungsfähigkeit (Societys complexity and collective ability to act), ed. Schimank, U. (2000). Frankfurt/Main: Campus, pp. 154–182 [http://pubman.mpdl.mpg.de/pubman/faces/viewItemFullPage.jsp;jsessionid=1F12495443EF6AC95BFF12F29F3C4829?itemId=escidoc%3A1235032%3A2&view=EXPORT book summary at the Max Planck Gesellschaft] {{Webarchive|url=https://web.archive.org/web/20141012202222/http://pubman.mpdl.mpg.de/pubman/faces/viewItemFullPage.jsp;jsessionid=1F12495443EF6AC95BFF12F29F3C4829?itemId=escidoc%3A1235032%3A2&view=EXPORT |date=12 October 2014 }}</ref>

The ozone treaty has been ratified by 198 parties (197 states and the [[European Union]]),<ref name="ozone.unep.org">{{cite web |url=http://ozone.unep.org/Ratification_status/ |title=Status of Ratification – The Ozone Secretariat |publisher=Ozone.unep.org |access-date=10 March 2008 |archive-url=https://web.archive.org/web/20141008112847/http://ozone.unep.org/Ratification_status/ |archive-date=8 October 2014 |url-status=dead }}</ref> making it the [[List of treaties by number of parties|first universally ratified treaty]] in United Nations history.<ref>{{cite web |url=http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=2666&ArticleID=9010&l=en |title=UNEP press release: 'South Sudan Joins Montreal Protocol and Commits to Phasing Out Ozone-Damaging Substances' |publisher=Unep.org |access-date=11 July 2012 |archive-date=4 March 2016 |archive-url=https://web.archive.org/web/20160304093536/http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=2666&ArticleID=9010&l=en |url-status=dead }}</ref>

This truly universal treaty has also been remarkable in the expedience of the policy-making process at the global scale, where only 14 years lapsed between a basic scientific research discovery (1973) and the international agreement signed (1985 and 1987).