By Phil Franz-Warkentin, Commodity News Service Canada
Winnipeg, Dec. 3 – After record ice levels kept shipping lanes on the Great Lakes closed longer than normal during the 2013-14 winter, a return to more normal ice conditions is in the forecast for 2014-15, according to data compiled by the North American Ice Service and released Dec. 3.
“Right now, we’re looking at a near normal season for ice conditions on the Great Lakes,” said Scott Weese, senior ice forecaster with the Canadian Ice Service, which is a department of Environment Canada and a member of the North American Ice Service. “Near normal, in comparison with last year, means less ice,” he added.
Long range forecasts studied by the Canadian Ice Service are pointing to a near normal temperature regime, which means progressive low pressure systems moving across the region bringing cold outbreaks, followed by warmer conditions, said Weese.
In 2013-14 “we had a pattern that anchored the cold air over the Great Lakes and led to progressive and steady thickening (of the ice . . . we just didn’t see the warm-ups to slow the growth of the ice,” said Weese.
“We see more variability in a normal regime,” he added.
This year, “we did have some early and unusual ice development in some of the northern areas of Lake Superior,” said Weese.
However, as a sign of the return to more variability in temperature; after the initial cold outbreaks, conditions have warmed, slowed the ice development, “and in some cases led to destruction of that early ice.”
This year the last of the winter ice was still melting in June, “which was quite late,” while a return to normal would see all of the ice gone by late April, said Weese.
The shipping season at the Port of Thunder Bay, located on the northern shore of Lake Superior, typically runs from late-March through December, but thick ice on the Great Lakes last winter meant that the first ship didn’t move until late April in 2014.