A winter storm is set to bring ice to portions of the Midwest this weekend, but the Great Lakes remain largely ice-free.
Great Lakes ice coverage is currently sitting at only 1.8% total for all of the five lakes combined. That’s way below the average of 15% that we normally see by this date.
“It is very unusual to be this low but not uncommon to be low on this date,” explains CNN Meteorologist Michael Guy.
As of January 10, this is the second lowest ice coverage recorded on the Great Lakes. The record for lowest ice coverage was set in 2007 with .31% coverage. These records go all the way back to 1973.
In fact, since 1973, the Great Lakes have only been under 5% on this date a total of 15 times, including this year. For some perspective, last year at this same time Great Lakes total ice coverage was at 3.6%.
This is good news for most people from an economic standpoint.
When the lakes completely freeze over, barges can no longer move through the lake, which has a big economic impact.
However, Dr. Jia Wang, senior ice climatologist at the National Oceanic and Atmospheric Administration’s Great Lakes Environmental Research Laboratory (GLERL), explains how this is not necessarily a good thing ecologically.
“For some species, no ice cover is not good for them because they need a safe place to lay eggs,” Wang said.
Lake Superior only has 0.5% of ice coverage right now, which limits the possible areas for these animals to lay their eggs. And for lakes like Erie and Ontario, where ice coverage is currently at 0%, these options are non-existent for those egg-laying species.
A cold blast of air is on the way for the Midwest by late next week. In fact, cities like Chicago, Detroit, and Green Bay are all expected to be about 10 degrees below average by next Friday. But Dr. Wang cautions that short-lived cold snaps don’t do much to increase the ice coverage quickly. He states that in order to make a big change, you need a continuous cooling event lasting at least 1-2 weeks.
Even if we were to get such a continuous cooling event this season, it may not make a difference. NOAA’s GLERL forecasts that the maximum total ice cover will be 47% this winter. The historical average for the basin is 55%.