Stratospheric ozone depletion - an overview of the scientific debate

Abstract

For almost half a century it was widely believed that the photochemistry of the stratosphere and hence ozone distribution were well understoood. As observations revealed a gap between observed and predicted values it was recognized that a number of substances acted as catalysts thereby increasing the destruction of ozone and that humanity could augment those catalysts and affect the ozone layer.Initial concern focused on nitrogen oxides from the exhausts of supersonic transport, but attention switched in the mid-1970s to chlorofluorocarbons (CFCs). Although the theory of anthropogenic ozone depletion by CFCs found widespread scientific support the perceived threat was minimized in particular by successive model predictions downgrading the amount of depletion. The appearance of the ozone hole over Antarctica in the mid-1980s reopened the debate as to whether such depletion was anthropogenic or natural in origin. It also highlighted the model's inadequate treatment of the processes occurring in the stratosphere and the importance of dynamics and radiative transfer in stratospheric ozone destruction. Scientific consensus again favours the anthropogenic depletion of the ozone layer. In conclusion it is considered that the degree of consensus outweighs the image of scientific uncertainty that is often portrayed in relation to the issue of stratospheric ozone depletion.

The Effect of Supersonic Transports on the Global Environment: A Debate Revisited

“…The advanced SST would have to meet increasingly strict noise standards (Cross 1986;Nordwall 1999). At the same time, concerns over CFCs and the ozone hole have led to a greater scientific appreciation of stratospheric ozone depletion (Drake 1995;Solomon 1999). In particular, it is now recognized that the presence of aerosol surfaces aids the destruction of ozone.…”

Polyurethane foams containing renewable castor oil replacement

“…Besides water, there are also other types of blowing agents, such as chlorofluorocarbons, which are liquid in standard state and then vaporize after absorbing enough heat produced from the synthesis of polyurethane. However, since chlorofluorocarbons are considered a major cause of stratospheric ozone depletion (Drake, 1995), the application and production of chlorofluorocarbons have been strictly limited.…”