Page 6057 - Week 18 - Thursday, 12 December 1991
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If we look at Antarctica, we find that there is a problem over Antarctica with a lessening of the amount of ozone in the stratosphere. One might ask: Why is that? There is a particular phenomenon that usually is in place in winter over Antarctica and which creates a vortex caused by westerly winds. That causes the air there to be particularly dry and the emanations of hydrochloric acid gas from Mount Erebus, which is not too far from McMurdo Sound, do not have the opportunity to break up as they normally would. Because of that, it rises up into the stratosphere.
You do get a lot of chlorine in the stratosphere, in the ozone layer over Antarctica, basically, in winter. There is no doubt about that whatsoever. By the time spring runs along you do not have that problem again. One of the ideas is that, certainly, it may be that that causes the problem. But this problem was not just discovered, as we were told; it was discovered a long time ago. The researchers working with Dobson maintain that it is not a problem. For the past year Marcel Nicolet, the founder and director of the Institut Aeronomie Spatiale de Belgique in Brussels, has largely refuted claims that CFCs are depleting the ozone layer. Nicolet, one of the pioneer researchers of the ozone layer, was working with Gordon Dobson in 1956 when they discovered the Antarctic ozone hole.
He maintains that the ozone hole is a natural oscillation of the weather systems, which increases and decreases periodically. It is worthwhile to have a look at a couple of the people who initially released information saying that there was a concern. I think it was back in 1974 that two chemists from the University of California, F. Sherwood Rowland and Mario Molina, wrote the first technical paper concerning CFCs. Because there are so many difficult chemical reactions in the stratosphere, it is very hard to isolate a particular chemical reaction, reproduce it in a laboratory and say, "Look, if you do this you get that".
It was possibly because of that that they carefully prefaced their paper with the following qualifier:
We have attempted to calculate the probable sinks and lifetimes of these molecules.
Unfortunately, such disclaimers never made it into the press. That was not heard about any more, and the press grabbed this thing and said, "Away we go". From then on it was accepted as proof.
If we look at the basic problem - which is with chlorine, I believe - does it come only from people that are smashing up fridges or motor car air-conditioning units? I will not say "spraying things from cans" because, of course, that is not done any more out here. But let us say that it was being done. The amount of chlorofluorocarbons or CFCs being pushed out by that particular method is not much at all when you compare it with certain other areas.
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