Rowland-Molina Hypothesis

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  Comprehensive Study on Problems arising from Exploitation of Natural Resources, A

  • (Author)
  • 2014(Publication Date)
  • University Publications

    (Publisher)

  Thus human activity could have an impact on the stratospheric ozone layer. In the following year, Crutzen and (independently) Harold Johnston suggested that NO emissions from supersonic aircraft, which fly in the lower stratosphere, could also deplete the ozone layer. The Rowland-Molina Hypothesis In 1974 Frank Sherwood Rowland, Chemistry Professor at the University of California at Irvine, and his postdoctoral associate Mario J. Molina suggested that long-lived organic halogen compounds, such as CFCs, might behave in a similar fashion as Crutzen had proposed for nitrous oxide. James Lovelock (most popularly known as the creator of the Gaia hypothesis) had recently discovered, during a cruise in the South Atlantic in 1971, that almost all of the CFC compounds manufactured since their invention in 1930 were still present in the atmosphere. Molina and Rowland concluded that, like N 2 O, the CFCs would reach the stratosphere where they would be dissociated by UV light, releasing Cl atoms. (A year earlier, Richard Stolarski and Ralph Cicerone at the University of Michigan had shown that Cl is even more efficient than NO at catalyzing the destruction of ozone. Similar conclusions were reached by Michael McElroy and Steven Wofsy at Harvard University. Neither group, however, had realized that CFCs were a potentially large source of stratospheric chlorine — instead, they had been investigating the possible effects of HCl emissions from the Space Shuttle, which are very much smaller.) The Rowland-Molina Hypothesis was strongly disputed by representatives of the aerosol and halocarbon industries. The Chair of the Board of DuPont was quoted as saying that ozone depletion theory is a science fiction tale...a load of rubbish...utter nonsense.

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  Protecting the Ozone Layer

  The United Nations History

  • Stephen O Andersen, K Madhava Sarma, Stephen O. Andersen, K.Madhava Sarma(Authors)
  • 2012(Publication Date)
  • Routledge

    (Publisher)

  ‘Rarely does Nobel-prize-winning research galvanize worldwide political action. Yet the findings that have made chemistry laureates of Sherwood Rowland of the University of California at Irvine, Mario Molina of MIT [Massachusetts Institute of Technology], and Paul Crutzen of Germany’s Max Planck Institute for Chemistry did just that. Their discovery that man-made chemicals can damage the planet’s protective ozone layer was instrumental in triggering the most successful global environmental treaty ever written: the 1987 Montreal Protocol limiting the use of chlorofluorocarbons, or CFCs

  ‘Crutzen’s work came first, with his demonstration in 1970 that airborne chemicals called nitrogen oxides could damage the ozone gas that floats high in the Earth’s stratosphere and screens out ultraviolet light, which can cause sunburn and skin cancer. The real breakthrough, though, came in 1974, when Molina and Rowland determined that CFCs are highly efficient ozone destroyers, gobbling up many times their volume in ozone molecules.

  ‘Molina’s and Rowland’s work didn’t thrill industrialists, but it did lead to a ban on CFC-based spray cans in the US in 1978. And after an ozone hole over Antarctica was detected in 1985, industry was goaded into taking swift action.’

  The Nobel Prize ‘landed like a vindication’ on scientists whose ‘work was long overlooked by the scientific establishment,’ according to the Los Angeles Times (12 October, 1995). Molina said the award to environmental scientists ‘shows a certain maturity in a field previously considered soft.’ Rowland said he had received ‘many messages from people in the environmental area saying they are doubly pleased – both by our getting the prize, but also by the fact that problems of the environment are being recognized.’

  New research on the environmental fate and impact of the hydrofluorocarbon (HFC) and HCFC substitutes for CFCs found that some of the compounds degraded in the atmosphere to form trifluoroacetate. Trifluoroacetate is removed from the atmosphere as trifluoroacetic acid which is mildly toxic to some marine species, but would never reach toxic concentrations in the environment; trifluoroacetic acid would ultimately end up in the oceans, and the large dilutions would result in extremely low concentrations.

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  Business Power and Conflict in International Environmental Politics

  • R. Falkner(Author)
  • 2017(Publication Date)
  • Palgrave Macmillan

    (Publisher)

  Industry persisted in arguing that there was no case for regulation in the first place, and by urging for an international solution, it sought to weaken the anti-CFC campaign in the US. Emphasizing scientific doubts seemed to payoff in the early days of the ozone debate. As the Molina-Rowland theory came to be scrutinized by other scientists, questions emerged that led the two researchers to acknowledge that the photochemistry involved in ozone depletion was more complicated than they had originally assumed, and that estimates of ozone depletion had to be revised downward (Rowland and Molina, 1976). As a consequence, the National Academy of Science, which was Ozone Layer Depletion 59 carrying out a major research assessment exercise on behalf of the US government, delayed the publication of its report for several months and recommended that regulatory decisions be postponed in light of the scientific uncertainties (Litfin, 1994: 65). The ensuing scientific debate raised further questions and produced contradictory findings, without fully invalidating or confirming the original hypothesis. Given the lack of a scientific consensus, industry felt vindicated that further research was needed before regulations are enacted. However, this strategy depended crucially on industry maintaining a united front in its lobbying efforts. Although at first all CFC user industries had rallied behind the public pronouncements of the leading chemical firms, the commercial and political strategies of producers and user industries began to diverge. Dwindling consumer confidence in their CFC-based products compelled certain users to reassess their strategy. For them, the technical and economic feasibility of replacing CFCs became a crucial factor in deciding whether or not to oppose demands for CFC restriction - irrespective of the scientific merits of these demands.

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