Montreal Agreement 1987
Chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS) are now recognized worldwide as the leading cause of observed ozone depletion (1-5). Molina and Rowland (6) first recognised the potential of CFCs to deplete stratospheric ozone in 1974, giving an `early warning`. This scientific warning has led to a reduction in ODS emissions through citizen actions and national regulations (7, 8). A decade later, the discovery of the hole in the ozone layer over Antarctica (9) and the subsequent allocation to the ozone layer (10, 11) further increased concerns. The 1987 Montreal Protocol on Substances that Deplete the Ozone Layer formally recognized the significant threat posed by ozone-depleting substances posed by ozone-depleting substances and provided a mechanism to reduce and phase out the global production and consumption of ozone-depleting substances. Under the Montreal Protocol and national regulations, the production, use, emissions and observed atmospheric concentrations of CFC-11, CFC-113, methyl chloroform and several other ODS (4, 12-14) have decreased significantly, and there is new evidence of a recovery in stratospheric ozone (4, 15). In an “averted world” where early warning of 1974 and the Montreal Protocol of 1987 are lacking, ozone depletion would probably be much greater than that observed in our world today. OdP-weighted emissions (left), GWP-weighted emissions (middle) and RF (right) for the ODS and CO2 scenarios for the period 1960-2020. Calculated GWP-weighted emissions (100-year time horizon) and associated RF values are displayed for four scenarios: Baseline, MR74, NMP87 and SRES CO2. All emissions are normalized to the equivalent of GtCO2·an−1 by their direct GWPS (see also the legend in Fig. 1).
The indirect contribution to GWP due to ozone depletion, estimated at ≈20% (see text), is not included in these figures. The shaded areas for MR74 reflect a range of 3 to 7% for the assumed annual increases in production of CFC-11 and CFC-12 from 1975 and an annual increase of 3% for the other ODS from 1987 onwards. Shaded areas for NMP87 reflect a range of 2-3% for assumed annual increases in production in all ODS. Stripes in shaded areas indicate the greatest uncertainties after 2010. CO2 emissions for the period 1960-2003 come from the global production of fossil fuels and cement (45). After 2003, the shaded areas for CO2 reflect the maximum (A1B) and minimum (B2) (25) SRES scenarios. CO2-HF data are based on CO2 observations and SRES scenarios (25). All RF values represent the net changes from the beginning of the industrial era (≈1750) to the present day. For reference, the magnitude of the reduction target for the first commitment period of the Kyoto Protocol is presented, which is based on a projection of the global increase in greenhouse gas emissions from 1990 to 2010 and the average reduction target for participating countries (see text) (36).
In the 1970s and 1980s, the international community became increasingly concerned that ozone-depleting substances could damage the ozone layer. In 1985, the Vienna Convention for the Protection of Excitation of the Ozone Layer formalized international cooperation on this issue. This cooperation led to the signing in 1987 of the Montreal Protocol on Substances that Deplete the Ozone Layer. Until the 23rd. In June 2015, all United Nations countries, the Cook Islands, the Holy See, Niue and the European Union ratified the original Montreal Protocol (see external link below)[42], with South Sudan being the last country to ratify the agreement, bringing the total to 197. These countries have also ratified the London, Copenhagen, Montreal and Beijing amendments. [12] Also in 1985, 20 countries, including most of the major producers of CFCs, signed the Vienna Convention, which provided a framework for the negotiation of international regulations on ozone-depleting substances. [37] Following the discovery of the hole in the ozone layer by SAGE 2, it took only 18 months for a binding agreement to be reached in Montreal, Canada. The United States signed the Montreal Protocol in 1987 and paved the way for the treaty`s successes. Over the past 30 years, the EPA has proudly contributed to the broad coalition that has developed and implemented flexible, innovative, and effective approaches to protect the stratospheric ozone layer.
In 1995, the United Nations designated 16 September as International Day for the Protection of the Ozone Layer, also known as World Ozone Day. The second scenario is the Molina and Rowland scenario (hereinafter referred to as the MR74 scenario), which represents a world-wide approximation of ODS growth and atmospheric concentrations, which was avoided due to their early warning and subsequent actions taken by consumers and governments prior to the Montreal Protocol. The scenario begins in 1975 (figs. 1 and 2) with an increase in CFC-11 and CFC-12 in the reference scenario with a range of annual growth rates of 3 to 7%. The difference above the reference scenario quickly becomes significant, with an annual growth rate of 7% leading to a doubling in a decade. The rate of 7% is well below the growth rates reported for the period 1960-1974 (Fig. 1) and may therefore underestimate the initial growth. The higher rate is consistent with previous scenarios (29) based on annual emissions growth of 7 % from 1980 to 2030 and is also very similar to the growth rate of an analysis previously formulated using an ODS “free market” scenario (30).
Taking all these and other factors into account, the Montreal Protocol is considered one of the most successful environmental agreements of all time. What the Parties to the Protocol have achieved since 1987 is unprecedented and remains an inspiring example of what international cooperation can achieve at its best. The Parties to the Montreal Protocol agreed on a phase-down of HFCs at their 28th Meeting of the Parties on 15 October 2016 in Kigali, Rwanda. Countries agreed to include HFCs in the list of controlled substances and approved a timetable for their gradual reduction from 80 to 85% by the end of the 2040s. The first reductions by industrialized countries are expected in 2019. Developing countries will follow with a freeze on HFC consumption in 2024 and 2028 for some countries. The Montreal Protocol on Substances that Deplete the Ozone Layer is a global agreement to protect the Earth`s ozone layer by progressively depleting the chemicals that deplete it. This phase-out plan covers both the production and consumption of ozone-depleting substances. This historic agreement was signed in 1987 and entered into force in 1989. The Parties to the Protocol meet once a year to take decisions with a view to ensuring the successful implementation of the Agreement.
This includes adapting or modifying the protocol, which has been done six times since its inception. The most recent amendment, the Kigali Amendment, called for the phasing out of hydrofluorocarbons (HFCs) in 2016. These HFCs were used as a substitute for a batch of ozone-depleting substances that were phased out by the original Montreal Protocol. Although they do not deplete the ozone layer, they are known as strong greenhouse gases and therefore as the cause of climate change. The Copenhagen Amendment (1992)Exit significantly accelerated the phasing out of ODS and, from 2004, included the phasing out of hydrochlorofluorocarbons (HCFCs) for industrialized countries. Under this agreement, CFCs, halons, carbon tetrachloride and methyl chloroform are expected to be phased out completely in developed countries in 1996. In addition, methyl bromide consumption has been limited to 1991 levels. More information on the withdrawal of ODS is available here. September 16 is World Oceans Day, marking the anniversary of the signing of the Montreal Protocol on Substances that Deplete the Ozone Layer, the historic international agreement focused on healing the ozone layer and protecting our planet from harmful ultraviolet (UV) rays. To learn more about World Ozone Day, check out this reportExitand the history of the Montreal Protocol and its implementation in the United States. But the CFC industry didn`t give up so easily.
As recently as 1986, the Alliance for Responsible CFC Policy (an association founded by DuPont that represents the CFC industry) argued that the science was too uncertain to warrant action. In 1987, DuPont testified before the U.S. Congress: “We believe there is no imminent crisis that requires unilateral regulation.” [38] And even in March 1988, Du Pont`s president, Richard E. Heckert, wrote in a letter to the U.S. Senate: “We will not manufacture a product unless it can be manufactured, used, handled, and disposed of safely and in accordance with appropriate safety, health, and environmental quality criteria. At present, the scientific evidence does not indicate the need for a drastic reduction in CFC emissions. There are no available measures of the contribution of CFCs to observed changes in the ozone layer. [39] The Montreal Protocol on Substances that Deplete the Ozone Layer is the historic multilateral environmental agreement that regulates the production and consumption of nearly 100 man-made chemicals called ozone-depleting substances (ODS). When released into the atmosphere, these chemicals damage the stratospheric ozone layer, earth`s protective shield that protects humans and the environment from the sun`s harmful ultraviolet rays. .