Ice cover at record low level on Great Lakes

Ice coverage in the Great Lakes is at the lowest level that has ever been recorded for this point in the year, the National Oceanic and Atmospheric Administration announced Friday.

Maximum ice coverage typically happens between mid-February and early March, NOAA said in a news release. At this point in the year, coverage is typically between 35-40% of the lakes, but as of Feb. 16, only 5.8% of the lakes are covered.

Experts say the biggest factor affecting the ice cover is air temperatures. January was a warm month on the Great Lakes and across the United States — and the seventh-warmest January in at least 174 years, as far back as records are kept.

Cooler temperatures in early February boosted ice coverage up 21% across the Great Lakes basin, NOAA said, but it has declined since.

Ice coverage varies from year to year, but NOAA research has noted a "downward trend" in ice cover in recent years, the agency said in its release. The average ice cover between 1973 and 2017 saw average ice cover decline about 70%.

That could cause problems for those living on the Great Lakes.

"Less ice cover means more open water, which is a perfect set up for lake-effect snow," Ayumi Fukisaki-Manome, an assistant research scientist at the Cooperative Institute for Great Lakes Research based at the University of Michigan, said in a statement. "Also, ice cover protects the shoreline of lakes. Without it, high waves can scour the coastline and cause flooding."

It can also spell trouble for winter recreation, Fukisaki-Manome said — ice fishing, for example, could prove less safe as ice is not as stable.

Ice formation got off to a slow start this season.

Randy Carlon, dock master of Holiday Isle Marina in Spring Lake near Grand Haven, told The News that as of mid-January there hadn't been a single day he could walk out on the ice of the west Michigan lake.

Warm temperatures are likely to continue through much of the state in the next few days, according to National Weather Service forecasts. In Detroit, the weekend is predicted to be warm — a high of 43 degrees on Saturday and a high of 50 on Sunday, with temperatures in the mid-40s continuing into the week.

Warming is what Richard Rood, a professor of climate and space sciences and engineering at UM's College of Engineering, called "the most robust signal of climate change in the Great Lakes region."

"That warming is greatest in the winter, and during warm weather patterns, it is for more likely to be above freezing than in the past," Rood said in a university news release.

"We see signals of a shift from snow to rain. We see winter snow storms, which can have record snow amounts, followed by rain and melting. The message? There is definitive warming. There is an accumulation of heat and its effects throughout the basin. Declining lake ice is part of this coherent story of accumulation of heat."

Staff Writer Sarah Rahal contributed.

hharding@detroitnews.com