Darn, I missed the United Nation’s “World Ozone Day” celebration on September 16. The UN announced: “Just over a quarter-century ago, the world united to reverse the rapid depletion of the atmospheric ozone layer, which protects Earth from harmful radiation from space. Today, the ozone layer is well on track to recovery within the next few decades.” That announcement refers to the alleged success of the Montreal Protocol that banned chloro-fluoro-carbons (CFCs) which were claimed to thin the ozone layer which protects us from ultraviolet radiation.
Atmospheric ozone is produced by ultraviolet (UV) radiation breaking down oxygen. Ozone thinning at the South Pole normally occurs in winter when sunlight and UV rays disappear allowing the normally unstable ozone to decay. Ozone (O3, a variant of the oxygen molecule O2) produces smog when it is at ground level, but high in the atmosphere, ozone protects us from ultraviolet radiation from the Sun. Atmospheric ozone is naturally unstable. The amount and extent of decay apparently depends on cosmic ray flux.
Some background on this issue:
Back in 1956, scientists noticed that the atmospheric ozone layer seasonally thinned over the South Pole. The size of the ‘hole’ varied from year to year. The reigning theory as to the cause of this ‘hole’ was that CFCs reacted with the ozone and caused its destruction leaving us vulnerable to UV radiation. This theory led to the Montreal Protocol, an international treaty promoted by the United Nations. It went into effect in 1989 and required a phase-out of all CFCs which, at the time were used mainly in refrigerators, air-conditioning units, and to a lesser extent, as propellants for medicinal inhalers.
The alleged science behind this ban, according to Wikipedia, is this:
In 1973 Chemists Frank Sherwood Rowland and Mario Molina, then at the University of California, Irvine, began studying the impacts of CFCs in the Earth’s atmosphere. They discovered that CFC molecules were stable enough to remain in the atmosphere until they got up into the middle of the stratosphere where they would finally …be broken down by ultraviolet radiation releasing a chlorine atom. Rowland and Molina then proposed that these chlorine atoms might be expected to cause the breakdown of large amounts of ozone (O3) in the stratosphere. Their argument was based upon an analogy to contemporary work by Paul J. Crutzen and Harold Johnston, which had shown that nitric oxide (NO) could catalyze the destruction of ozone.
In other words, the catalytic reaction of CFCs on ozone was hypothesized based on “might be expected” and by “analogy.” However, there still is no proof that it actually happens in nature on a large scale.
The first chink in the CFC-ozone hypothesis came in 2007 with an article in Nature: “Chemists poke holes in ozone theory.” Chemists at NASA’s Jet Propulsion Laboratory that the rate of photolysis (light-activated splitting) of CFCs was much slower than had been assumed. This means: “The rapid photolysis of Cl2O2 is a key reaction in the chemical model of ozone destruction. If the rate is substantially lower than previously thought, then it would not be possible to create enough aggressive chlorine radicals to explain the observed ozone losses at high latitudes.”
So, if it’s not CFCs, what might be causing the variation in ozone? A possible answer was presented by researcher Qing-Bin Lu (University of Waterloo, Canada) in Physical Review Letters of the American Physical Society, 19 March 2009:
This Letter reports reliable satellite data in the period of 1980–2007 covering two full 11-yr cosmic ray (CR) cycles, clearly showing the correlation between CRs and ozone depletion, especially the polar ozone loss (hole) over Antarctica. The results provide strong evidence of the physical mechanism that the CR-driven electron-induced reaction of halogenated molecules plays the dominant role in causing the ozone hole.
Independent research from Cornell, published in 2010, also found a correlation between cosmic rays and the size of the ozone ‘hole.’
Anthony Watts opines in his blog that the recent UN announcement is purely political science. Watts notes:
Within the span of nine months, NASA issued statements claiming of atmospheric ozone that “signs of recovery are not yet present,” there is “large variability,” it is “stabilizing,” and now, that the ozone problem is “recovering”.
So which is it? The answer may lie in the relevant political science, not the atmospheric. The Montreal Protocol is 25 years old this year, having been entered into force in 1989. When such milestones are reached, there is always pressure to make some statement that the work of the UN actually made some sort of difference.
Watts also notes that the Chinese have been scamming the process:
“It appears that Chinese coolant manufacturers have been producing an excess of a harmful greenhouse chemical in order to dispose of it responsibly under the UN’s Clean Development Mechanism (CDM). By using incinerators to cleanly burn off the chemical, HFC-23, these manufacturers were earning emission credits that they would in turn sell to developed world companies in order to help them hit their targets under the Kyoto Protocol.”
Since the science points to cosmic rays as the chief variable in size of the ozone hole, it seems that the UN is taking credit for a natural process. Politics have conflated a natural phenomenon into an environmental bogeyman that required a government solution to an imaginary problem.