CHICAGO - Lake Michigan's most recent ice cover analysis shows it has dropped back below average. At this point of the year the amount of ice on the lake should be close to its highest point. The average peak coverage of 39.8% occurs on February 13th. It is now below 20%.
There are year-to-year fluctuations in ice cover on the Great Lakes but there has been a troubling long-term trend. The annual maximum ice cover is, on average, 22% lower that it was a half-century ago across all of the Great Lakes.
Current Ice Coverage On Lake Michigan
The most recent analysis of the Great Lakes shows 29.8% ice coverage. That is more than the past two previous years at this point but well below average for mid-February. The average peak ice coverage for the entire lake system is around 54%.
Great Lakes Ice Coverage
Climate change is chipping away at the ice. The lake ice season is shrinking. The lakes are tending more often to freeze over later and to thaw out sooner.
Climate Central did a study of how the ice cover has been changing over the past half-century. The drop in ice cover means "not only are they vital sources of drinking water and irrigation for the country as a whole, cultural and recreational practices connected to the lakes and lake ice are deeply rooted in the surrounding communities. From ice fishing to skating, traditional ceremonial practice and the use of ice roads, the endurance of a rich variety of historical and cultural connections with Great Lakes ice is at risk of slipping through our fingers as a result of climate change".
The decline in ice cover for Lake Michigan isn't as dramatic as the Great Lakes as a whole but it is still impressive.
Climate change is having the biggest impact on winter compared to the other seasons. Winters in the northeast and Great Lakes regions have warmed as much as a 5° over the past half century. A decline in ice cover can mean lower water levels, warmer water and increased sunlight penetration. The greater sunlight penetration can have an influence on water quality and make it tougher for native fish populations to survive.
The Great Lakes holds 90% of the freshwater in our country and 20% of the world's total supply. Fishing on the lakes boosted the U.S. economy by more than $2 billion in 2016 with over 11 million fishing trips in total. Ice fishing was a part of that but it is increasingly becoming more difficult and dangerous as the ice cover thins.