In , Joseph C. Farman and his colleagues at BAS studied the raw data and found that stratospheric ozone had decreased greatly since the s. The Antarctic ozone hole, as it came to be known, made depletion of the ozone layer a real and present danger to lawmakers and the public at large. Predictions of significant increases in the incidence of skin cancer resulting from continued use of CFCs spurred international action. In , 56 countries agreed under what became known as the Montreal Protocol to cut CFC production and use in half.
In subsequent years, the protocol was strengthened to require an eventual worldwide phaseout of the production of CFCs and other ozone depleting chemicals.
It is a global problem. What is important is that it led to an international agreement that solved the problem. Their unprecedented advocacy ultimately led to the phasing out of CFCs worldwide through the passage of the Montreal Protocol in The research of Rowland and Molina brought worldwide attention to the impact of human-contributed pollution on a planetary scale. Their work was among the first to directly effect a global shift in policy, preceding the current debate on climate change.
ACS designated F. The commemorative plaque reads:. At the University of California, Irvine, F. When the scientists reported their findings in , CFCs were widely used as refrigerant gases and as propellants in aerosol sprays. Rowland and Molina convinced skeptical industrialists, policymakers, and the public of the danger of CFCs. Chlorofluorocarbons and Ozone Depletion.
Back to Landmarks Main Page. Learn more: About the Landmarks Program. Landmarks Lesson Plans. Careers Launch and grow your career with career services and resources. The final deal divided the world economies into three groups, each with a target phasedown date.
The richest countries, including the United States and those in the European Union, will reduce the production and consumption of HFCs from The multilateral fund that allows this process to work by compensating poorer countries and paying for transfers of newer technology to them is highly dependent on US support. To date, the US had not ratified the agreement.
This kind of multilateral fund is important in levelling the playing field and could also be replicated in other areas where lack of access to new technology might slow down shifts towards a low carbon economy. North America. Clean energy. Safe water. Enough money.
Efficient travel. Secure rights. Good food. Better homes. Liveable cities. Natural advantage. Decent work. Story of change. Back from the brink: how the world rapidly sealed a deal to save the ozone layer Posted on 11 June Wider relevance The success in negotiating, strengthening and enforcing the Montreal Protocol should give hope to embattled climate change negotiators around the world — as it is evidence that multilateral initiatives can be effective in tackling the global environmental challenges we face.
Context and background Chlorofluorocarbons CFCs are chemicals that were developed in the s which, before they were banned, were used in a wide array of commercial and industrial processes. Enabling factors Key to the rapid transition to phase out CFCs was the widespread acceptance amongst the general public, business actors and world leaders of the severity and urgency of the problem; a consensus that was forged following the discovery of the ozone layer in Scope and evidence It took only 2 years from the discovery of the ozone layer in for governments to agree to a global ban on the use of CFCsand a further 2 years for it to come into effect.
The Montreal Protocol is the only treaty ever to achieve universal ratification; with countries enforcing the ban on CFCs. Global observations have confirmed that atmospheric levels of key ozone depleting substances are going down and it is expected that by the middle of this century they will return to pre levels.
Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative. Environmental Science and Pollution Research Advanced search. Skip to main content Thank you for visiting nature. Download PDF. Reaction data of crucial chloride compounds called into question. The hole in the ozone layer blue over Antarctica results from chemicals such as CFCs.
References 1 Pope, F. Authors Quirin Schiermeier View author publications. Rights and permissions Reprints and Permissions. About this article Cite this article Schiermeier, Q. Copy to clipboard. Varotsos Environmental Science and Pollution Research Search Search articles by subject, keyword or author.
Show results from All journals This journal. Resent research suggests that the strength of the polar vortex from any given year is directly correlated to the size of the ozone hole. In years with a strong polar vortex, the ozone hole is seen to expand in diameter, whereas in years with a weaker polar vortex, the ozone hole is noted to shrink.
Introduction The atmosphere of the Earth is divided into five layers. Figure courtesy of NASA. The Chapman Cycle The stratosphere is in a constant cycle with oxygen molecules and their interaction with ultraviolet rays. Chemistry of Ozone Depletion CFC molecules are made up of chlorine, fluorine and carbon atoms and are extremely stable. Figure courtesy of NOAA.
Because Antarctica is surrounded by water, winds over the continent blow in a unique clockwise direction creating a so called "polar vortex" that effectively contains a single static air mass over the continent. As a result, air over Antarctica does not mix with air in the rest of the earth's atmosphere. Antarctica has the coldest winter temperatures on earth, often reaching F.
Due to their extremely cold temperatures, PSC's form an electrostatic attraction with CFC molecules as well as other halogenated compounds As spring comes to Antarctica, the PSC's melt in the stratosphere and release all of the halogenated compounds that were previously absorbed to the cloud.
Taken directly from the Clean Air Act, as of June The Chemistry and Physics of Stratospheric Ozone. Ozone Depletion and Climate Change. Protecting the Ozone Layer: Science and Strategy.
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