Switzerland’s glaciers are shrinking, they have been shrinking ever since 1922, and last year’s figures, recently given out by Professor P. L. Mercanton, director of the Swiss Meteorological Office, indicate that the shrinkage is not only being maintained but seems to be accelerating.
So far as it goes, this tends to confirm glaciologists in their theory that glaciers move in great cycles of alternate advance and retreat extending over periods of roughly, 36 years each.
If this theory is correct, the glaciers of the Alps should continue retreating until ,1957, when another great cycle of advance should set in.
(they had to wait until ~1960)
One might easily assume that it would be a hopeless task to cope with the confusion of movement which is always at work in the snout of a huge glacier. There would be no snout at all if it were not for the fact that the glacier has descended to an altitude at which it thaws more rapidly than it renews itself.
In the winter, when its thaw stops, or is greatly retarded, it pushes, on down at its rate of an inch, a foot, or a couple of feet a clay. In the summer, when its thaw is renewed, and it wastes more rapidly than its rate of advance can renew it, the snout retreats until another winter gives it a chance.
Always, on top of this ceaseless confusion of movement, there are the great cycles of alternate advance and retreat which the glaciologists are at tempting to chart in the theory which they call the Bruckner theory.
But to the glaciologist this is simple enough. The end of winter’ is the time ol’ the maximum seasonal advance, and therefore the movement for the annual measurement to be taken.
Professor Mercanton, in the collected 1933 measurements which ‘he has now announced, tells U3 that the great Allalin glacier, each of the Rimpfisch horn above Zermatt, retreated 30ft. last year.
The Ficsch glacier, to the east of the Eggishorn above the Rhone valley, retreated ‘ 33ft. The. Trient, the northernmost glacier of the Mont Blanc range, retreated 481t, while the Oberaar and Unteraar, in the vast nest of glaciers to’ the east, the Jungfrau, retreated 93ft. and 62ft. respectively.
Of the total of 100 Swiss glaciers which were measured, four were at a standstill, 15 were advancing, and 81 retreating. Ten years ago the annuial measurements indicated that, of the same 100, 12 were at a standstill, 22 were advancing, and 66 were retreating.
The 1933 measurements accordingly fit into the Bruckner theory as nicely as those of ten years ago do, but glaciologists do not yet regard this theory of 35-year cycles of alternate advance and retreat as definitely established.
A century of glacier measurements in the Alps seems to support it, but glaciology moves so slowly that it takes more than a mere century to establish a new glacial law.
The glaciologists are able to tell us that the Alpine glaciers had a maximum of advance between 1810 and 1825 and another maximum along towards 1855, after which they all retreated.
About 1875 a slight tendency towards advance reappeared, they say, among the glaciers if the Chamonix region and worked gradually eastward, expiring in the Swiss Alps in 1893 and the Tyrolean Alps in 1901.
Meanwhile, a more marked advance: was setting in, and it was not until 1922 that it passed its peak and. descended into the present cycle of retreat. –
– The Canberra Times, ACT Monday 31 December 1934