The Montreal Protocol is gradually reducing the consumption and production of different ozone layers with different schedules for developed and developing countries (referred to as “Article 5 countries”). Under this agreement, all parties have special responsibilities with respect to the withdrawal of different groups of ODS, the control of ODS trade, annual reporting of data, national licensing systems for the control of ODS imports and exports, and other matters. Developing and developed countries have the same but different responsibilities, but above all the two groups of countries have binding, time-bound and measurable commitments. After almost a decade of talks, on October 15, 2016, on October 28. The Meeting of the Parties to the Montreal Protocol in Kigali, Rwanda, reached a historic agreement on the phase-out of hydrofluorocarbons (HFCs), substitutes for CFCs which, although not harmful to the ozone layer, are a growing source of powerful greenhouse gases that contribute to climate change. On 1 January 2019, the Kigali Amendment entered into force. The amendment has now been ratified by 65 Parties, exceeding the 20 ratifications required for its entry into force. Since the entry into force of the Montreal Protocol, atmospheric concentrations of the main chlorofluorocarbons and associated chlorinated hydrocarbons have stabilized or decreased. [43] Halon concentrations have continued to increase as halons currently stored in fire extinguishers are released, but their rate of increase has slowed and their frequency is expected to decrease by approximately 2020.

The concentration of HCFC has also increased significantly, at least in part, as many uses (e.g. B, used as solvents or refrigerants) have been replaced by HCFCs. Although there have been reports of attempts by individuals to circumvent .B ban, for example by smuggling CFCs from underdeveloped to developed countries, the overall level of compliance was high. Statistical analyses from 2010 show a clear positive signal from the Montreal Protocol to stratospheric ozone. [44] As a result, the Montreal Protocol has often been considered the most successful international environmental treaty to date. In a 2001 report, NASA noted that the thinning of ozone over Antarctica had remained the same thickness over the past three years,[45] but in 2003 the ozone hole reached its second largest size. [46] The most recent scientific assessment (2006) of the effects of the Montreal Protocol states: “The Montreal Protocol works: there is clear evidence of a decrease in atmospheric exposure to ozone-depleting substances and some early signs of a recovery of stratospheric ozone.” [47] However, a recent study seems to suggest a relative increase in CFCs due to an unknown source. [48] For each group of ODS, the contract provides a schedule according to which the production of these substances must be excluded and possibly stopped.

This included a 10-year phase-in for developing countries[17], as provided for in Article 5 of the Treaty. HFCs are widely used in refrigeration and air conditioning, foam blowing and other applications. Although they now account for less than 1 per cent of global greenhouse gas emissions, HFCs are extremely potent greenhouse gases, the use of which is expected to increase rapidly, particularly in developing countries. The Montreal Protocol, formerly the Montreal Protocol on Substances that Deplete the Ozone Layer, an international treaty adopted in Montreal on 16 September 1987, to regulate the production and use of chemicals that contribute to the depletion of the Earth`s ozone layer. Originally signed by 46 countries, the treaty now has nearly 200 signatories. The international treaty, known as the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol), phases out the production and consumption of ozone-depleting substances in order to limit their degradation of the Earth`s ozone layer. The Montreal Protocol is signed by 197 countries – the first treaty in the history of the United Nations to be universally ratified – and is considered by many to be the most successful global environmental action. The treaties are also distinguished by the unique opportunity for global action, with only 14 years between the discovery of basic scientific research (1973) and the signing of the international agreement (1985 and 1987). On October 15, 2016, 197 U.S.-led countries adopted an amendment in Kigali, Rwanda, to phase out HFCs under the Montreal Protocol. As part of this change, countries have committed to reducing the production and consumption of HFCs by more than 80% over the next 30 years.

The ambitious roadmap for gradual degradation will prevent more than 80 billion tonnes of carbon dioxide equivalent emissions by 2050 and avoid warming of up to 0.5° Celsius by the end of the century, while continuing to protect the ozone layer. As part of this change, developed countries will reduce their HFC consumption from 2019 onwards. Most developing countries will freeze consumption in 2024, while a small number of developing countries with unique circumstances will freeze consumption in 2028. The plan also provides funding for some countries to help them transition to climate-friendly alternatives. .