Warm Winter, Lack of Great Lakes Ice

February 16, 2012; 10:45 AM ET
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This winter ranks high on the list for lack of Great Lakes ice cover, thanks to amazing warmth stemming back through the fall of 2011.

Temperatures have averaged from 5 to 10 degrees above normal since Dec. 1, 2011, from western New York and northwestern Pennsylvania to northern Wisconsin and northeastern Minnesota.

The number of cold waves have been far too infrequent and too weak to cause significant ice formation on the Great Lakes.

January 2012 was the fourth-warmest January on record for the contiguous United States.

According to Environment Canada, as of Feb. 5, 2012, just over 5 percent of the Great Lakes waters are covered in ice.

Only during the winters of 2001-2002 and 2005-2006 was the percentage of ice less than 10 percent at this stage in the winter. During the winter of 2005-2006, there was slightly less ice on the lakes as there is now. Records date back to the winter of 1980-1981.

Typically, during the second week in February, the percentage of ice on the Great Lakes is around 30 percent. Ice coverage typically peaks during the middle of March near 40 percent then falls sharply during the spring.

According to Canada Weather Expert Brett Anderson, "The latest indications are that the ice cover for this season may have already peaked."

Ice cover as of Feb. 14, 2012. Image courtesy of the National Weather Service.

While the weather pattern moving forward this spring will have the upper hand in temperatures downwind of the Great Lakes, the warmer the waters are to start (with less ice), the more positive the impact on temperature.

The same weather pattern with mostly frozen Great Lakes waters would negatively affect temperatures in downwind areas.

While lake effect can still occur over a frozen lake surface, open waters generally translate to more substantial lake-effect snow.

With the lack of ice on the Great Lakes, it is also possible that we have unusually heavy lake-effect snow well into the spring, assuming a cold enough blast of air passes over the waters to induce lake effect in the first place.

According to the Lake Carriers Association, iron ore shipments were up 24 percent from a year ago and were 57 percent ahead of the five-month average.

The iron ore trade finally shut down on Feb. 10 for the season.

If indicators of the Great Lakes ice are correct, the iron ore trade may not have to wait long to resume shipments.


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