The Montreal Protocol 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 nine revisions, in 1990 (London), 1991 (Nairobi), 1992 (Copenhagen), 1993 (Bangkok), 1995 (Vienna), 1997 (Montreal), 1998 (Australia), 1999 (Beijing) and 2016 (Kigali) As a result of the international agreement, the ozone hole in Antarctica is slowly recovering. Climate projections indicate that the ozone layer will return to 1980 levels between 2040 and 2066. Due to its widespread adoption and implementation, it has been hailed as an example of successful international co-operation. Former UN Secretary-General Kofi Annan stated that "perhaps the single most successful international agreement to date has been the Montreal Protocol". 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. 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.
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is about 0.3 parts per million. The ozone layer is mainly found in the lower portion of the stratosphere, from approximately 15 to 35 kilometers (9 to 22 mi) above Earth, although its thickness varies seasonally and geographically.
Ozone depletion consists of two related events observed since the late 1970s: a steady lowering of about four percent in the total amount of ozone in Earth's atmosphere, and a much larger springtime decrease in stratospheric ozone around Earth's polar regions. The latter phenomenon is referred to as the ozone hole. There are also springtime polar tropospheric ozone depletion events in addition to these stratospheric events.
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propane.
'Freon' is a registered trademark of the Chemours Company and generic descriptor for a number of halocarbon products. They are stable, nonflammable, low toxicity gases or liquids which have generally been used as refrigerants and as aerosol propellants. These include chlorofluorocarbons (CFCs) and Hydrofluorocarbons (HCFCs) --- both of which cause ozone depletion and thus contribute to global warming. 'Freon' is the brand name for the refrigerants R-12, R-13B1, R-22, R-410A, R-502, and R-503 manufactured by The Chemours Company, and so isn't used to label all refrigerants of this type. It emits a strong chemical smell similar to acetone, a common nail polish remover component.
Bromomethane, commonly known as methyl bromide, is an organobromine compound with formula CH3Br. This colorless, odorless, nonflammable gas is produced both industrially and biologically. It has a tetrahedral shape and it is a recognized ozone-depleting chemical. It was used extensively as a pesticide until being phased out by most countries in the early 2000s.
Dichlorodifluoromethane (R-12) is a colorless gas usually sold under the brand name Freon-12, and a chlorofluorocarbon halomethane (CFC) used as a refrigerant and aerosol spray propellant. In compliance with the Montreal Protocol, its manufacture was banned in developed countries in 1996, and in developing countries in 2010 out of concerns about its damaging effect on the ozone layer. Its only allowed usage is as a fire retardant in submarines and aircraft. It is soluble in many organic solvents. R-12 cylinders are colored white.
Chlorodifluoromethane or difluoromonochloromethane is a hydrochlorofluorocarbon (HCFC). This colorless gas is better known as HCFC-22, or R-22, or CHClF
2. It was commonly used as a propellant and refrigerant. These applications were phased out under the Montreal Protocol in developed countries in 2020 due to the compound's ozone depletion potential (ODP) and high global warming potential (GWP), and in developing countries this process will be completed by 2030. R-22 is a versatile intermediate in industrial organofluorine chemistry, e.g. as a precursor to tetrafluoroethylene.
1,2-Dichlorotetrafluoroethane, or R-114, also known as cryofluorane (INN), is a chlorofluorocarbon (CFC) with the molecular formula ClF2CCF2Cl. Its primary use has been as a refrigerant. It is a non-flammable gas with a sweetish, chloroform-like odor with the critical point occurring at 145.6 °C and 3.26 MPa. When pressurized or cooled, it is a colorless liquid. It is listed on the Intergovernmental Panel on Climate Change's list of ozone depleting chemicals, and is classified as a Montreal Protocol Class I, group 1 ozone depleting substance.
Environmental harmful product dumping is the practice of transfrontier shipment of waste from one country to another. The goal is to take the waste to a country that has less strict environmental laws, or environmental laws that are not strictly enforced. The economic benefit of this practice is cheap disposal or recycling of waste without the economic regulations of the original country.
The Vienna Convention for the Protection of the Ozone Layer is a multilateral environmental agreement signed in 1985 that provided frameworks for international reductions in the production of chlorofluorocarbons due to their contribution to the destruction of the ozone layer, resulting in an increased threat of skin cancer.
Chloropentafluoroethane is a chlorofluorocarbon (CFC) once used as a refrigerant and also known as R-115 and CFC-115. Its production and consumption has been banned since 1 January 1996 under the Montreal Protocol because of its high ozone depletion potential and very long lifetime when released into the environment. CFC-115 is also a potent greenhouse gas.
1,1-Dichloro-1-fluoroethane is a haloalkane with the formula C
2H
3Cl
2F. It is one of the three isomers of dichlorofluoroethane. It belongs to the hydrochlorofluorocarbon (HCFC) family of man-made compounds that contribute significantly to both ozone depletion and global warming when released into the environment.
Rajendra Madhavrao Shende, an alumnus of Indian Institute of Technology (IIT) and former Director in United Nations Environment Programme (UNEP), is currently serving as the Chairman of TERRE Policy Centre which is a not-for-profit organization engaged in the policy development and project based advocacy on the sustainable development. Before August 2011, he was the Head of the OzonAction Branch of the United Nations Environment Programme, Division of the Technology, Industry and Economics in Paris.
1-Chloro-1,1-difluoroethane (HCFC-142b) is a haloalkane with the chemical formula CH3CClF2. It belongs to the hydrochlorofluorocarbon (HCFC) family of man-made compounds that contribute significantly to both ozone depletion and global warming when released into the environment. It is primarily used as a refrigerant where it is also known as R-142b and by trade names including Freon-142b.
OzonAction is a branch of the United Nations Environment Programme (UNEP) which has its main office in Paris, and is part of UNEP's Division of Technology, Industry and Economics (DTIE). Created in 1991, today it has staff located in five regional offices of UNEP, namely in Africa, Asia & the Pacific, Latin America and the Caribbean, and West Asia.
Stephen Oliver Andersen is the Director of Research at the Institute for Governance & Sustainable Development (IGSD) and former co-chair (1989–2012) of the Montreal Protocol Technology and Economic Assessment Panel (TEAP) where he also chaired and co-chaired Technical Options Committees, Task Forces and Special Reports. He is one of the founders and leading figures in the success of the Montreal Protocol on Substances that Deplete the Ozone Layer that has phased out the chemicals that deplete the stratospheric ozone that protects the Earth against the harmful effects of ultraviolet radiation that causes skin cancer, cataracts, and suppression of the human immune system, destroys agricultural crops and natural ecosystems and deteriorates the built environment. Because ozone-depleting chemicals are also powerful greenhouse gases the Montreal Protocol also protected climate. Dr. Andersen was instrumental in the 2016 Kigali Amendment that will phase down hydrofluorocarbons once necessary to phase out chlorofluorocarbons (CFCs) fast enough to avoid ozone tipping points, but no longer necessary now that environmentally superior replacements are available or soon to be available. For his ambitious campaign saving the ozone layer, Dr. Andersen earned the 2021 Future of Life Award along with Joe Farman and Susan Solomon.
Ozone depletion and climate change, or Ozone hole global warming in more popular terms, are environmental challenges whose connections have been explored and which have been compared and contrasted, for example in terms of global regulation, in various studies and books.
K. Madhava Sarma (1938-2010) was the first Executive Secretary of the Vienna Convention for the Protection of the Ozone Layer and the Montreal Protocol on Substances that Deplete the Ozone Layer from 1991 to 2000 at the United Nations Environment Programme (UNEP). He is considered one of the founders and leading figures in the success of the Montreal Protocol that established legally binding controls on the production and consumption of chemicals that cause ozone depletion and damage the stratospheric ozone layer which protects the Earth against the harmful effects of ultraviolet radiation. These effects include skin cancer, sunburn, permanent blindness and cataracts as well as harm to plants and animals. The Montreal Protocol was recognized by Kofi Annan, former Secretary General of the United Nations as being “perhaps the single most successful international environmental agreement to date" and went on to become the first treaty in the history of the United Nations to be universally ratified in 2008 by 197 countries.
The Kigali Amendment to the Montreal Protocol is an international agreement to gradually reduce the consumption and production of hydrofluorocarbons (HFCs). It is a legally binding agreement designed to create rights and obligations in international law.
