WORLD CLIMATE CHANGES

Sun (Auckland), Volume III, Issue 922, 15 March 1930, Page 16

WORLD CLIMATE CHANGES

NEW ZEALAND PROFESSOR ON CAUSES ANTARCTIC DISCOVERIES The discovery by members of Byrd’s Antarctic Expedition of i traces of coalfields other than | those found by previous expedi- ! tions has further emphasised the j fact that at some period in the distant past a temperate climate prej vailed in those regions now bound | by the rigours of snow and ice, and it is interesting to hear the | views c» Professor R. Speight, Professor of Geology at Canterbury College, Christchurch, as to i the probable cause of this change. ! Professor Speight pointed out that not by traces of coalfields alone was it indicated that a temperate climate was once enjoyed in both the Arctic and Antarctic regions. There was evidence of the existence of plant life and animals. In the South Shetland Islands evidence of the existence of many trees now flourishing in New Zealand had been found. It had been suggested that these traces might be the result of driftwood gathered there, but this was discountenanced by evidence concerning its actual growth. In other parts of the world—in India and Aus-tralia, for instance — there were glacial formations which clearly indicated that at those parts a polar or semi-polar climate had once prevailed. No satisfactory explanation as to how such tremendous changes of climate had been brought about had yet been advanced, but scientists throughout the world had from time to time formulated certain theories. One was that the climate of the world as a whole had changed. In ans wer to this it had been pointed out that even had the climate changed it could not have eliminated the six-months period of darkness that was experienced at the Poles. This being so, it was doubtful whether tree and plant life could have flourished through that period. All kinds of astronomical explanations had been advanced, and it was suggested also that various radio activities may have been contributory causes. One of the most interesting theories that was advanced by a German surveyor named Wegner. He suggested that the continents of the world had drifted, indeed were still drifting, and that factor would account for changes in cl imate. Since he advanced his theory geologists and scientists had criticised it, and today his arguments were maintained to be unsound. However, a considerable body of Continental geologists was agreed that Wegner’s conclusions were reasonable. If one accepted that theory, it certainly explained many difficulties geologists were contending with today. Referring to some observations regarding Greenland's position to Europe, that were carried out some years ago, Professor Speight said that recent observations showed that the two continents had altered slightly ■their positions. Some authorities, however, asserted that the earlier observations had not been correct, due to faulty instruments. Any movement would naturally be very small, and only by taking observations over long periods could definite results be obtained.