Common ozone depletion myths There is overwhelming evidence that humans are responsible for the Antarctic ozone "hole". And there is strong evidence that the ozone layer elsewhere has been damaged. Three scientists who developed the ozone depletion theory were awarded the Nobel Prize in chemistry. With so much evidence for an environmental crises, it is little wonder that so many anti-environmental myths have developed about ozone depletion. Common myths about ozone depletion:
Myth: CFCs cannot reach the stratosphere because they are heavier than air.
Fact: Air in the lower atmosphere (which extends far above the stratosphere) moves in masses, not as individual molecules. A number of studies have found CFCs and the products of their breakdown in the stratosphere (Rowland, EPA).
Myth: Volcanoes and other natural sources contribute much more chlorine than CFCs to the ozone layer.
Fact: Chlorine compounds from natural sources are soluble, and so are washed out of the atmosphere. CFCs, by contrast, are not soluble and so are able to reach the stratosphere. A number of studies have shown that the majority of chlorine in the stratosphere comes from man-made chemicals (Rowland, Taubes, Russell et al, EPA). EPA
Myth: The Antarctic ozone "hole" was there all along, it was discovered in the 1970's because that's when satellite measurements started.
Fact: The hole was discovered using a ground based instrument that had been in use since There was no hole until about That means about 20 years with no hole. Since the 70s the hole has continued to increase in size and intensity (Farman, et al, Jones & Shanklin).
Myth: The "hole" was present when the first measurements were made in 1956.
Myth: The "hole" was present when the first measurements were made in Fact: The first ozone measurements made in the Antarctic were lower than similar measurements made in the Arctic. However, this is the natural condition, not the decrease that is referred to as the ozone "hole". As noted above, there was no "hole" during the first 20 or so years of measurement. (Parson, Christie).
Myth: Some French researchers found an ozone hole in 1958.
Fact: Paul A. Newman (Newman) looked at all the facts and found that "There is no credible evidence for an ozone hole in 1958.“
Myth: Spray cans deplete the ozone layer.
Myth: Spray cans deplete the ozone layer. Fact: Spray cans (in the United States) have not used CFCs as propellants for about 20 years.
Myth: Of course there is an ozone hole in the winter, there is no sunlight to make new ozone.
Myth: Of course there is an ozone hole in the winter, there is no sunlight to make new ozone. Fact: The ozone hole occurs in the spring, after the sunlight returns. There is little destruction or creation of ozone during the winter (Parson)
Myth: DuPont supported the ban on freon because the patent was about to run out.
Myth: DuPont supported the ban on freon because the patent was about to run out. Fact: The patent for making freon was issued in 1928, it ran out in the 1940s, long before any concern about ozone depletion. (The History of Freon)The History of Freon
References Christie, Maureen, The Ozone Layer: A Philosophy of Science Perspective, Cambridge University Press, 2000The Ozone Layer: A Philosophy of Science Perspective Farman, et al., "Large Losses of Total Ozone in Antarctica Reveal Seasonal ClO x /NO x Interaction", Nature, May 16, 1985, pp Jones & Shanklin, "Continued Decline of Total Ozone over Halley, Antarctica, since 1985", Nature, August 3, 1995 pp Newman, Paul A., "Antarctic Total Ozone in 1958", Science, April 22, 1994, pp Parson, Robert wrote a lengthy FAQ on ozone depletionParson, Robert wrote a lengthy FAQ on ozone depletion, the best source of information I have found. Rowland, Sherwood, "The Need for Scientific Communication with the Public" Science, June 11, 1993, pp Russell, et al, "Satellite Confirmation of the Dominance of Chlorofluorocarbons in the Global Stratospheric Chlorine Budget" Nature, February 8, 1996, pp Taubes, Gary, "The Ozone Backlash", Science, June 11, 1993, pp