By Wally Crouch
8 June, 1958
MAN himself may be making the world hotter and creating the crazy, mixed-up weather like Sydney had this week.
Don’t scoff — the world’s top scientists are quite serious. In the U.S. scientists are probing a theory that pollution of the atmosphere is making the earth
New cities spring up, factories are built, smoke and smog belch everywhere, Jet planes and rockets shoot out exhaust fumes —and year by year the pollution gets worse.
Some scientists suspect that increased carbon di-oxide and other gases in the atmosphere are acting as a “greenhouse,” thus stopping the earth from losing some of its heat to outer space.
The U.S. Government has taken this theory so seriously that its weather experts are taking samp-les of upper air in the An-tarctic and other remote regions to check on it.
The project is among many which nations have undertaken in the 1957-58 Geophysical Year to find out how—and why — the earth is setting warmer.
Two weather experts in Australia, Prof. J. MacDonald Holmes and Dr. E. B. Kraus, this week told me about the project.
They mentioned lots of other theories, too—the earth changing its solar alignment, increased sunspot activity, bigger falls of meteorites into the earth’s atmosphere, and even that more recent bogey, nuclear weapon tests.
Scotsman Holmes, Professor of Geography at Sydney University, and Czech-born Dr. Kraus, a top – flight weatherman now working for the Snowy Hydro Authority at Cooma, have more than a passing interest in Sydney’s recent weird weather
With colleagues all over the world — geographers, geologists, meteorologists, and physicists—they are studying a bewildering pattern of melting glaciers, rising tides and unpredictable climates.
The research involved has to cover many thousands of years, great gaps in records man has kept, and many, many unexplained factors.
But somehow, somewhere, Sydney’s current spell of Indian summer fits Into the climatic puzzle.
Today we are still living near the end of the last of the four Ice Ages because the retreat of ice from Europe didn’t begin until 25,000 years ago.
None of these four Ice Ages ever completely covered the earth, though they considerably changed the face of Australia—and its climate.
But just how, and in what cycles, we don’t know because, unlike Europe, there were no civilised men here to keep records, Sydney Weather Bureau records go back only to 1859, and no one there has bothered to keep a comparative check on likely climatic cycles.
About 10,000 years ago —which is as far back as Professor Holmes and his associates are trying to check Australia’s climatic variations — the continent was a colder and wetter place than it is today. Mount Kosciusko had a perennial ice-cap of at least 3000 feet, says Professor Holmes, though nowadays its annual winter snow may not exceed three or four good falls.
Australia’s sea-level at that time was about 73ft, lower than at present, fore the melting ice regions sent it higher.
Professor Holmes there is very definite evidence that in the past 30-35 years, glaciers in Central Europe, North America, New Zealand, Greenland, and New Guinea have been retreating.
Part evidence of this are greater deposits of moraine — rock and dirt retreating glaciers leave behind.
Scientists are now eagerly awaiting data from the recent Fuchs-Hillary expeditions to the Antarctic, which are expected to show that the massive polar ice-caps there are melting.
“All over the world there are other signs of increasing warmth,
“With colored butterflies their ‘melanism’ —pigmentation — is becoming darker, a sure sign of increased heat.
In northern Norway for trees are dying out and giving way to spruce, a warmer weather species.
Over the top of Europe the pack-ice is retreating, and the Arctic Ocean there is becoming more navigable.
With a little man-made help from ice-breakers the Russians hope soon to have a clear waterway from the Barents Sea right
round to the Bering Sea, north of the Pacific.”
Recent changes in the world’s “heat equator” also bear out the “warmer world’ theory, says Professor Holmes.
This “heat equator” is a flexible line which traces the highest mean temperatures right round the earth annually.
In northern latitudes the “heat equator” pinpoints “hot spots” over the oceans; south of the Equator it zigzags over the land masses.
And in recent years the “heat equator” has been shifting more and more to the south, including Australia.
And what about Australia? Professor Holmes says that up to recent years it was generally accepted that the continent’s weather moved in 35-year cycles.
Some experts have since traced it to 11-year cycles, and now there is a theory that the climate here may be governed by five-year cycles.
For example, this winter appears to be following last year — dry, mild, and with clear skies, and the summers very hot and drought-creating.
In the previous five years —1952-56—eastern Australia had a lot of rain—including some heavy flooding—in both winter and summer, and cold, biting winds and frequent snow
in the winter.
Bad weather invariably passes over Australia from west to east and comes from one of two areas where low-pressure fronts originate — the Great Australian Bight-Tasman Sea region, or the tropical waters north of Australia.
Clear, dry weather flows from high pressure “fronts” originating in the desert regions of Western and Central Australia.
Lately, “highs’’ have extended and moved along paths more to the north and south.
“These so-called ‘good’ winters should last for at least three more years before the cycle changes,” he adds.
DR. KRAUS believes the world’s average mean temperature has risen approximately one degree over the past 100 years.
In some parts of the Northern Hemisphere, like Greenland, the extreme tip of Scotland, and the northern tip of Canada, the increase was as much as three degrees, but in Australia it was only a fraction of a degree.
But, according to a survey he made, rainfall in eastern Australia, especially in Queensland’s subtropical belt, rose about 20 per cent between 1850-1950.
This increased coastal moisture may justify our complaints about Sydney’s being summers humid.
What happens when the world’s average mean temperature rises a degree?
Because the transition is slow — over at least a century, possibly 300-400 years — humans and animals suffer no physical ill effects.
But nature changes; warm weather crops can be grown in regions where previously they would have perished.
Insects, too, invade new areas; sometimes with detrimental effects, like the tsetse fly in Africa, which has been found in areas where it wasn’t a century ago.
What about the danger from rising tides? Neither our generation nor the next should have to worry, say Prof. Holmes and Dr. Kraus.
Sydney’s present high tides appear to be caused by a general southward movement of tropical waters, which is running late this year.
They’re no higher than at Christmas — their normal “highest,”
For the world’s tidal level to rise 5ft, its average temperature would have to rise 2.8 degrees.
So a catastrophe, like the drowning of all coastal cities, isn’t due for about 1000 years — if at all.