The Great Lakes has been losing ice cover for nearly 40 years at a rate of 71 percent overall. Climatologists attribute the overall ice decrease to global warming
As most Canadians relish the warmer-than-usual winter this year, climatologists, port authorities, shipping companies, cottage owners, and tourism operators have been fretting over the effects of this warmer seasonal weather in the Great Lakes.
Shrinking water levels
These concerned groups have already been worrying about the shrinking water levels experienced over the last few decades due to higher-than-normal temperatures. Now a new study, published in the Journal of Climate raises another cause for concern: the Great Lakes are losing ice cover and have been for nearly 40 years.
This new finding was part of a research study published recently in the Journal of Climate. Climatologists at the National Oceanic and Atmospheric Administration’s Great Lakes Environmental Research Laboratory studied historical satellite measurements, Coast Guard records, and other sources from 1973 to 2010.
They found that the total loss for all the Great Lakes ice coverage was 71 percent over the period. Lake Ontario showed the greatest loss at 88 percent with Lake Superior second at 79 percent. The study authors noted that factors such as El Nino-La Nina phases may be a factor, but they attribute the overall ice decrease to global warming.
Shrinking ice coverage may, on the surface, seem like a good thing, as cargo shipping is a large factor in the Great Lakes’ economy. But since ice inhibits evaporation, the less ice on the water, the less water. This is a decidedly bad thing for enormous cargo freighters that ply the Great Lakes and their channels, as they run the risk of bottoming out.
Other economic effects are felt by cottage owners, who are forced to extend docks as water recedes from their shores. And some tourism operators are seeing fewer visitors and more wear and tear on rental boats as they hit ground or rocks in the low waters. Many also spend large sums to continually dredge their marina channels.
Close to ecosystem collapse?
Pollution, invasive species, shrinking water levels: according to the National Wildlife Federation, the Great Lakes are “veering close to ecosystem collapse.” This is just one more sad tale to tell about a body of water that, put together, contain a fifth of the world’s fresh water.