Canada's warmest winter on record

The warmest winter on record could have far-reaching effects on everything from wildfire season to erosion, climatologists say, while offering a preview of what the season could resemble in the not-so-distant future unless steps are taken to cut greenhouse gas emissions.

Winter comes to a close on Tuesday night – early Wednesday on Canada's East Coast – with the arrival of the spring equinox. But climatologist David Phillips says it's almost as if this winter in Canada never happened.

"I called it the lost season," said Phillips, a senior climatologist with Environment and Climate Change Canada.

Canada shattered temperature records this winter, and it wasn't close, Phillips said, referring to national data going back to 1948.

While winter's end is typically marked by the equinox, climatologists look at what's known as meteorological winter, the three-month period from December to February. Over that period, Canada was 5.2 C warmer than average, said Phillips. That's 1.1 degrees warmer than the previous record set in 2009-2010.

There were bouts of extreme winter weather across Canada, from a January deep freeze on the Prairies to a massive snowfall in the Maritimes in February. But the warmer-than-normal and unusual weather was widely felt across the country.

This winter, Phillips said, "was put on hold – and not on ice."

Some people may have been grateful for a break on heating bills or for periodic balmy days, but Phillips says the record-breaking temperatures upended Canada's winter way of life. Winter festivals were cancelled, ski resorts faced closures, and flora and fauna emerged prematurely. Remote First Nations in Ontario and Manitoba that depend on ice roads issued states of emergency due to poor conditions.

Outdoor skating, often regarded as a picture-postcard image of Canada's winter life, suffered too. Ottawa's iconic Rideau Canal skateway was open for a few days this winter, after the previous year's unprecedented season-long closure.

Damon Matthews, a Concordia University climate scientist who has tracked climate change's impact on retreating rinks, cited Wayne Gretzky and Joni Mitchell as he noted the place of outdoor skating in Canada's imaginings of winter.

Mitchell's longing for a "river I could skate away on," evoked in her 1971 song "River," may be shared not just by those who decamped to California, but by people across Canada this year and in years to come, he said. Gretzky's origin story of learning to play on outdoor rinks may be a story denied to other aspiring hockey players in southern Ontario.

"It's a shame that's the case," he said.

Experts say the drivers of this winter's record-breaking warmth include El Niño and human-caused climate change. Other related factors include record-high global ocean temperatures and residual heat from earlier in 2023.

El Niño, a natural climate phenomenon that typically comes around every two to seven years, was strong this year but not the strongest. The United Nation's World Meteorological Organization said its peak fell short of at least two other El Niño winters in 1997 and 2015.

"El Niño has contributed to these record temperatures, but heat-trapping greenhouse gases are unequivocally the main culprit,” WMO Secretary-General Celeste Saulo said in an update earlier this month, referring to a string of consecutive global monthly temperature records.

Climate change is expected to crank up temperatures in winter more than any other season in Canada, said Phillips, the Environment Canada climatologist. If the world continues to emit greenhouse gases on a "business as usual" scale until 2050, Phillips says his own community of Barrie, in central Ontario, could see winters as warm as this one on a regular basis around 2065.

Less snow on the ground for the spring melt means less water available to irrigate farmlands and replenish reservoirs. As snow melts, it also helps to reduce the risk of wildfires.

Almost all of Western Canada, northern Ontario and parts of northern Quebec were under drought conditions as of the end of February, says a recent update from Environment Canada. Parts of southern Alberta and northern British Columbia reported conditions typically seen once every 50 years.

"The drought season, the forest fire season – these are all to come, but sometimes the seeds of those are sown in the winter," said Phillips.

Great Lakes ice cover, which helps shield the shoreline from erosion during winter storms, also hit historic lows in February. Erosion concerns extend to coastal areas around the Gulf of St. Lawrence, including Prince Edward Island, said Phillips.

But there is a fine line between being clear about climate change's consequences and despairing about a preventable outcome, said Matthews, the Concordia climate scientist.

"We need to get our act together and stop arguing about, as a country, whether this is even an issue or a priority," he said, adding that Canada is "not stepping up the way we need to be."

"Outdoor skating is a consequence of that, but at the same time, there are many, many worse things that will happen if we don't get on with things."

This report by The Canadian Press was first published March 19, 2024.