Pollution effects outlined

Press, Volume CXI, Issue 32562, 23 March 1971, Page 14

Pollution effects outlined

The net result of the increased amount of carbon dioxide being injected into the atmosphere would be to increase the surface temperature by possibly as much as Ideg. Centigrade on a world-wide scale by the end of the century, Mr A. P. Ryan, the chief meteorologist in Christchurch, said in Christchurch last evening.

He was speaking on pollution—the world scene and local problems —at the monthly meeting of the Christchurch branch of the United Nations Association. Mr Ryan said that it was very difficult to obtain information on the increased level of carbon dioxide in the atmosphere, but a fairly reliable figure indicated that it had increased by about 14 per cent since the industrial revolution.

Not only Would the continued increase affect surface temperature, but it would also effect climate and weather, he said. It would, for example, increase the area in Which tropical cyclones formed, the length of the

cyclone season and the intensity of the cyclones. In some areas it might bring about changes that would make the areas largely uninhabitable. Another effect would be io shift the climate zones by a few degrees. There was a good deal of controversy about whether such a change would cause the ice caps to melt or whether it would start a new ice age. If the ice caps began to melt they would do so very rapidly at first and within a few decades nearly every coastal city in the world would be inundated.

My Ryan said that human activities such as combustion processes and current agricultural practices in many parts of the world were also affecting the transparency of the atmosphere by injecting dust into the area. This eventually could result in the formation of low cloud and fog and in the loss of ; surface temperature by about Ideg Centigrade. Speaking on the effect of pollution by jet aircraft, Mr Ryan said that the exhaust from aircraft engines left condensation trails which spread over a wide area. The ice crystals formed qften took a long time to evaporate. resulting in an increase in high cloud, In Denver, Colorado, for

instance, it had been estimated that in the last 10 years the density'of high cloud had approximately doubled, mainly because of increased aerial traffic. In the case of the proposed supersonic jets, one jet on a transatlantic crossing could inject 200 tons of carbon dioxide into the air. As this would be injected into the atmosphere at a level of about 55,000 ft it would stay there for a very long time. The eventual effect of this would certainly be a strong rise in surface temperature, he said.

Mr Ryan said, however, that pollution by liberating substances into the atmosphere was; only one aspect of the general pollution problem. There were also forms of noise pollution and visual pollution.

It was important that everyone. should realise that they had two alternatives to the problem, he said. They could either accept it as a fact of life and take the disadvantages that went with it, or they could take measures to prevent pollution reaching disaster levels. “We can’t do much about it unless we are prepared to accept restrictions both on our personal, liberty and on our standard of living,” he said. ' ’