ICE-AGE GLACIERS

Press, Volume C, Issue 29540, 15 June 1961, Page 13

ICE-AGE GLACIERS

Return Held Possible The great glaciers of the ice ages could well come back within a few thousand years, although there was no special reason to believe they would, Professor W. E. Powers, professor of physical geography at North-western University, Evanston. Illinois, said in Christchurch. “The time since the glaciers of the last ice advance melted is much shorter than some of the periods between the various glaciations.” said Professor Powers. "Although the world has warmed on average a few degrees since the beginning of this century, it was apparently warmer in Europe 6000 years ago than it is today. “We are unlikely to be able to predict future temperature changes with any certainty, however, until we can account for past changes. At present we have 30 or 40 theories to account for the ice ages, but not one which can be proved to the exclusion of the others. My personal opinion is that more than one agency was at work, which would explain why no one theory seems to be entirely and solely true.” Among the more likely theories, Professor Powers listed: the elevation of the continents to make mountains, so lowering the global average temperature: the uplifting of isthmuses to divert major ocean currents: the changing composition of the atmosphere, especially fluctuations in the carbon dioxide content; changes in the orbit of the earth: variations in the heat given out bv the sun.