Do the satellite images show the ice that is still in the great lakes?
"The season started early because of the cold, with ice cover reported as early as the end of November, as opposed to the normal mid-December," Leshkevich said. "With the Arctic vortex the ice kept building early in the season, more than normal in the 40 years of record that we have."
Another anomalous feature of the ice cover this winter has been what's called a "double maximum." The ice reached 88% in late February, then dropped down to about 60% before rising again to the maximum in early March. The last time that happened was in 1996, Leshkevich said.
The last time the lakes were more than 90% covered in ice was in 1994, at 90.7% coverage. Before that, it hadn't been that high since the record was set in 1979. The National Oceanic and Atmospheric Administration has been tracking ice cover on the Great Lakes for 40 years.
It's an unusual year for Lake Michigan, which doesn't normally gain much ice cover. On Monday, it was 90.5% covered in ice. The last time it reached that point was about 35 years ago, in 1979 when coverage was 92%, Wang said. The most ice Lake Michigan has ever had was in 1977, when 93% of the lake was covered.
The region could see several positive effects from the prodigious ice on the lakes, including Lake Michigan. For example, it could boost the fishing season, Leshkevich said. Some species of fish need a stable cover of ice to protect their spawning beds from winter storms.
The ice cover also may mean a cooler spring, which could protect food crops: Buds will come out later and be less likely to experience a killing frost.
And cooler lake temperatures into the summer may mean reduced evaporation, which could help lake levels. In February 2013, Lake Michigan and Lake Erie hit their lowest recorded levels, and the Milwaukee Journal Sentinel reported on 14 years of below-average water levels on the lakes. Levels have rebounded some since February 2013.
Finally, with little open water, evaporation during the winter is reduced, and in turn, so is "lake effect" snow. When lake effect snow occurs, a large amount of snow falls at a rapid rate in select spots because of frigid air moving over warmer lake waters. |
