Pretty Big Lakes?
If this keeps up, the “Great” in the Great Lakes may be a misnomer. Water levels in the Great Lakes are falling, which according to the story in today’s New York Times, is bad news for shipping. It also, when you stop to think about it, can’t be good news for all the wildlife that depend on the lakes, the tourism linked to fishing, those who get their drinking water from the lakes, etc.
Here’s how the NYT story sums up the cause:
Most environmental researchers say that low precipitation, mild winters and high evaporation, due largely to a lack of heavy ice covers to shield cold lake waters from the warmer air above, are depleting the lakes. The Great Lakes follow a natural cycle, their levels rising in the spring, peaking in the summer and reaching a low in the winter, as the evaporation rate rises.
In the past two years, evaporation has been higher than average, and not enough rain and snow have fallen in the upper lakes Ã¢â‚¬â€ Superior, Michigan and Huron Ã¢â‚¬â€ which supply water to the lower lakes, to restore the system to its normal levels, said Keith Kompoltowicz, a meteorologist at the Corps of EngineersÃ¢â‚¬â„¢ office in Detroit, which monitors water levels in the lakes.”