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Since the late 1970s, the use of CFCs has been heavily regulated because of their destructive effects on the ozone layer. After the development of his electron capture detector , James Lovelock was the first to detect the widespread presence of CFCs in the air, finding a mole fraction of 60 ppt of CFC-11 over Ireland .
The full extent of the damage that CFCs have caused to the ozone layer is not known and will not be known for decades; however, marked decreases in column ozone have already been observed. The Montreal and Vienna conventions were installed long before a scientific consensus was established or important uncertainties in the science field were ...
Scientists spent years campaigning for a ban on the ozone-damaging chemical CFC-11, but 30 years after it was phased out in the 1987 Montreal Protocol, someone somewhere is breaking the rules.
The largest Antarctic ozone hole recorded (September 2006) 2012 retrospective video by NASA on the Montreal Protocol The Montreal Protocol on Substances That Deplete the Ozone Layer [2] 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 is 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 (non-article 5 countries) in 1996, and in developing countries (Article 5 countries) in 2010 out of concerns about its damaging effect on the ozone layer. [5]
The ozone depletion potential (ODP) of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane (R-11 or CFC-11) being fixed at an ODP of 1.0. Chlorodifluoromethane (R-22), for example, has an ODP of 0.05. CFC 11, or R-11 has the maximum potential amongst chlorocarbons because of the ...
Trichlorofluoromethane, also called freon-11, CFC-11, or R-11, is a chlorofluorocarbon (CFC). It is a colorless, faintly ethereal, and sweetish-smelling liquid that boils around room temperature. [5] CFC-11 is a Class 1 ozone-depleting substance which damages Earth's protective stratospheric ozone layer. [6]
Research in the 1980s said that these man-made CFC compound compounds had opened a hole in ozone layer in the upper atmosphere or stratosphere that protects life on earth from UV radiation. [5] CFC-13's ozone depletion potential (ODP) is high— 1 [9] (CCl 3 F = 1)—it is categorized as a Class I in the IPCC's list of ozone-depleting ...