Climate change due to the use of fossil fuels is helping to create conditions for stronger storms, particularly in the Great Lakes region, climatologists and meteorologists say.
Posted at 4:13 p.m.
Jordan Omstead
The Canadian Press
Sarah Bauer woke up to a house that was shaking. She thought an earthquake might have struck near her home in Torrance, a village with many cottages in Ontario.
But when she looked outside, she saw that a massive tree had collapsed on her driveway under the weight of the rapidly accumulating snow, taking a power line with it.
“It was scary,” she testified.
The storm that hit parts of central Ontario in late November and early December was the largest in recent memory, meteorologists said, dumping 140 centimeters of snow on Gravenhurst, a town just south of Torrance.
Another round of intense lake-effect snow hit areas off Lake Huron this week, and more squalls are expected late in the week.
The regions off the Great Lakes are accustomed to heavy snowfall, earning them the title of Ontario’s “snow belt.”
Towards an intensification
And yet, something new is happening. Richard Rood, a climatologist who studies the Great Lakes, says lake-effect snowstorms will likely intensify as the planet warms.
“It’s probably best to interpret them as typical of the future rather than extremes of the past,” Rood, professor emeritus of climate and space sciences at the University of Michigan, told Ann Arbor.
Lake effect snow relies on a combination of a surge of cold Arctic air and the comparatively warmer water of the Great Lakes. As air passes over the lake, it absorbs moisture and dumps it onto downwind communities during snowfalls often characterized by intense, localized squalls.
These storms are typical of late fall or early winter, when lake temperatures are still relatively warm. In the depths of winter, ice cover helps reduce evaporation, meteorologist Arnold Ashton said.
“In general, we don’t have it as often in January and February, and certainly in February, because there is more ice on the lake,” said Mr. Ashton, senior meteorologist at Environment Canada.
But as the lakes warm, there is more heat and humidity for those bursts of arctic air to multiply, intensifying snowfall. As milder winters limit the extent of ice cover, these storms may extend longer into the season.
“The Gravenhurst snow apocalypse, which reached one and a half meters, occurred in late November, early December […]but with global warming, these events could continue,” said Mr. Ashton.
Gravenhurst was placed under a state of emergency for more than two weeks as crews cleared snow-covered roads and attempted to restore power to tens of thousands of customers. Stranded drivers had to be rescued on a highway that remained partially closed for almost three days.
After cutting down the fallen tree across their driveway, Sarah Bauer’s family in Torrance purchased one of the last available generators from a nearby Canadian Tire store, she said in a recent interview .
It took four days for their power to come back, she said, while for others it took more than a week.
“I’m really not used to this type of snow as quickly as it came,” said M.me Bauer.
Difficult to predict
Trying to predict the effects of climate change on winter weather involves some uncertainty, meteorologists say.
Warmer lakes could mean more severe snowstorms. But as winters get warmer overall, it is also possible that precipitation will increasingly come in the form of rain. Fluctuating temperatures could mean some heavy snowfall is followed by unseasonably warm weather, increasing the risk of winter flooding.
“In a nutshell, it’s a complicated issue and it’s really a kind of foggy crystal ball for the future,” Mr. Ashton argued.
According to a report published in 2019 by Canadian and American scientists, the Great Lakes basin has experienced an increase in precipitation greater than that of the rest of the United States over the last century, with rains and falls of snow heavier than usual.
The Great Lakes entered one of their warmest periods in decades this winter, spurred in part by the effects of the El Niño climate cycle, which peaked last winter.
As of early December 2024, four of five lakes have experienced higher average surface temperatures in the first 11 months of the year than any other period in the past three decades, according to the National Oceanic and Atmospheric Administration of the United States.
The lakes also had some of the lowest ice coverage last winter.
The intensification of lake-effect storms should give lakeside communities pause, according to climatologist Richard Rood.
“This should really make them think about how to deal with future storms,” he argued.
That’s exactly what Gravenhurst officials are seeking to do. A review meeting was planned for this month, said a spokesperson for the municipality. A report is also being prepared for the city council on the cause of the storm and the local response.
Sarah Bauer was heartened to see neighbors supporting each other through the worst of the storm.
She remembered how someone in her area used a snowmobile to help rescue an elderly neighbor from her snow-covered home and then offered her a place to stay.
“You could see the community coming together,” she said.
