Andy Volicek has been ice fishing at his cabin in Washburn County, Wisconsin, roughly 75 miles northeast of the Twin Cities, every year for more than two decades. But lately, unseasonably warm winters have forced Volicek to postpone his trips.
“Generally, the last 20-plus years, we’ve been able to get out ice fishing like right after Thanksgiving, right after deer hunting season,” he said. “I noticed the last couple of winters that the ice has taken longer to get safe.”
Last winter was the hottest on record in the contiguous United States, according to the National Oceanic and Atmospheric Administration, with the previous winter also ranking among the warmest in many states’ histories. The trend has been especially noticeable in Midwest states such as Wisconsin, where many communities depend on winter tourism and recreation that require cold and snowy conditions.
Historically, Wisconsin lakes would freeze over for an average of four months every year, according to data kept by the Wisconsin State Climatology Office, whose logs date back to the early 1850s. But climate change has shaved off more than a month from that number, meaning Volicek and other fishing enthusiasts in Wisconsin now get less than three months on average to partake in a beloved Midwest pastime.
“Last year was the second lowest on record, only a month and a half” of ice cover, said Steve Vavrus, the state’s climatology office director. “So you can very clearly infer that the climate has been warming.”
Minnesota, too, has lost an average of two weeks of ice cover over the past 50 years, according to state data, with some of the state’s most popular lakes losing almost three weeks of ice. Last winter also marked the lowest average ice cover measured on the Great Lakes since record-keeping began in 1973.
“What’s happened with climate change is we’ve taken the edge off winter. It doesn’t get as cold as it used to,” said Peter Boulay, a state climatologist with the Minnesota Department of Natural Resources “Over the last seven [Decembers], we’ve had six that were warmer than normal, which would also mean more sluggish ice formation.”
Minnesota and Wisconsin have warmed roughly 3 degrees Fahrenheit over the last century, and that warming has accelerated in recent decades. One way that has manifested itself, Boulay said, is that states like Minnesota see fewer extremely cold days each year compared to several decades ago.
“Here in the Twin Cities, we used to get down to minus 20 fairly commonly at least once in the winter,” he said, “and we don’t do that much anymore.”
Recent Spikes in Ice-Related Deaths
The recent warm winters have created especially dangerous conditions for anglers or anyone else venturing out onto frozen lakes or rivers, said Nicole Biagi, the ice safety coordinator for the Minnesota Department of Natural Resources.
Ice safety is also a particular concern for immigrant communities that don’t have experience on ice, including at smaller neighborhood ponds, a DNR spokesperson told the Star Tribune. Biagi said her department is working to reach those groups by sharing safety information in multiple languages and doing targeted outreach across the state.
While the overall number of deaths related to falling through the ice have gone down in Minnesota over the years, she said, the state has seen spikes in recent years when temperatures have been unusually high.
Last winter, for example, six people died after falling through the ice in Minnesota, according to state data, compared to the state average of three deaths per year. And in the winters of 2017 and 2018, which were also unseasonably warm, a combined 11 people died after falling through ice. Wisconsin doesn’t keep track of deaths related to falling through ice, according to an agency spokesperson.
Now as January brings this winter’s first bout of consistently cold weeks, safety officials like Biagi are trying to make sure everyone is taking the necessary precautions to protect themselves on the ice, including by reminding people that traversing frozen bodies of water is never 100 percent safe.
“Many parts of the state have seen sizable temperature swings over the past few weeks,” the Wisconsin Department of Natural Resources warned in a Jan. 3 email bulletin. “These sharp swings can create thin and unstable ice covers.”
The warnings come after several people—and vehicles—fell through the ice in recent weeks across the Upper Midwest, resulting in at least three fatalities. In early December, a 16-year-old boy in Minnesota drowned after falling through the ice and a 78-year-old man in Wisconsin drowned after breaking through the ice while skating.
Last week, an ice fisherman died after falling through a lake in Marquette County, Wisconsin. Authorities said he was driving an ATV when the ice broke. A day later, in Shawano County, Wisconsin, a deliveryman’s van broke through the ice on a different lake while bringing food to an angler who was ice fishing. The driver was able to pull himself out and survived.
“This winter, it seems like people are kind of just pushing the limits a little bit because we’ve had these past couple years of bad ice,” Biagi said. “People are just really excited to get out and use their equipment, and so maybe some are going out on ice that’s not quite thick enough.”
Biagi said people should always check the thickness of the ice and actually measure it with a tape measure. Ice should be at least four inches to walk on, between five and seven inches for snowmobiles, and at least 13 inches to handle trucks or other larger vehicles. It’s also critical that it’s clear ice, she added, not white ice, which forms when snow melts on top of the current ice cover and then refreezes.
“White ice is only about half as strong as the clear ice,” Biagi said. “So when you’re looking at ice thickness, you need to look for clear ice.”
Other safety tips officials recommend include:
- Carrying a cell phone and letting people know where you are going and when you’ll return home;
- Wearing some kind of personal flotation device or a “float coat;”
- Wearing special footwear to help prevent slips;
- Carrying a couple of spikes and a length of light rope in an easily accessible pocket to help pull yourself—or others—out of the ice;
- Avoiding traveling in unfamiliar areas or at night.
Winter Recreation Could Look “Drastically Different” in the Future
After three days of balmy 50-degree weather in mid-December, Volicek was aching to get out onto the ice in January, as temperatures dipped well below freezing, where they’ve stayed for the last two weeks.
Still, Volicek said, he wouldn’t call this winter normal. “This year, we were able to get out there probably a week later than I wanted to,” he said. “Last year was a very, very strange winter, and this year is better than last year, but it could be a little better.”
December brought notable temperature swings in both Minnesota and Wisconsin, federal weather logs show. Temperatures near La Crosse, Wisconsin, went from a high of 56 degrees to -6 degrees a week later, then up to 34 degrees before dropping to a low of -12 degrees the following week.
That’s the kind of up-and-down conditions that create thin and dangerous ice conditions, said Wisconsin climatologist Vavrus. “A lot of those ice anglers have a lot of experience to know when conditions are safe. But even so, they can get fooled sometimes,” he said. “There’s often surprises, especially with these big temperature swings.”
Those big temperature swings fit the broader trend in the Midwest during winter, said Stefan Liess, a researcher in the University of Minnesota’s Department of Soil, Water and Climate. Warmer temperatures brought about by climate change are injecting more energy into Earth’s weather systems overall, he said, and that can lead to larger swings between extreme highs and lows—though he noted that it’s largely because the extreme highs are growing so quickly.
“Unfortunately, it’s still the trend that winter is the season that gets warmest, the fastest … in Minnesota,” Liess said. “And therefore, the weather might be looking drastically different in a couple of decades.”