Don’t be fooled by the near-blizzards we’ve endured in recent weeks. The long, snowy winters of your childhood are gone forever. The vast, white fields of snow that blanket Canada are shrinking more every decade, particularly in Quebec.
The repercussions — social, economic and environmental — are everywhere. There is no way to reverse those changes in our lifetime, experts say, but we do have one last chance to mitigate the consequences.
CBC/Radio Canada analyzed snowfall data collected by Environment Canada since the 1950s. That winter, the season that defines this land and our identity, is changing is an undeniable fact.
When climatologists first began collecting ground snow data in Montreal, the maximum depth of the snowpack over the course of a winter was approximately 60 centimetres. That was the average for 20 years. Much more snow likely falls on the city, but it gets compacted once it hits the ground.
According to the most recent data, the maximum snow depth is now half of what it used to be.
In Quebec City, the maximum depth of the snowpack was more than one metre at the start of the data collection period. Once again, that was the average for 20 years. The latest available data shows that it is now just three-quarters of that.
The stations that measured the depth of the snowpack since the 1950s no longer collect that data. However, Environment Canada’s analyses of satellite imagery from the 1970s until the present also demonstrate that the country’s snow is in retreat.
“This reduction is directly linked to climate change,” says Ross Brown, an Environment Canada cryosphere scientist — an expert in snow cover. Brown says we’re seeing more winter days with temperatures above freezing.
Out of thousands of Environment Canada weather stations, CBC/Radio-Canada has identified 63 with complete historical data going back to at least the 1970s.
For 90 per cent of those stations, the data showed a decrease in the number of days when there was at least one centimetre of snow on the ground.
We also zeroed in on 153 stations with sufficient historical temperature data for our analysis.
For 99 per cent of those stations, that data showed the average winter temperature is trending upward.
In Montreal, the reduction of the depth of the snowpack has been so significant that three years ago, the city changed the way it pays snow-removal contractors. Contractors used to be paid according to how much snow fell. But now the snow melts more often than it used to, even in the middle of winter. Philippe Sabourin, spokesperson for the city, says Montreal now pays contractors according to the volume of snow they transport.
In the long run, the city hopes to save money with its new contracts, even if, for now, that’s not happening. The past two winters, frequent snowstorms have forced the city to dip into its budget reserves.
Philippe Sabourin is the spokesperson for the City of Montreal. (Nicolas Pham/Radio-Canada)
Brown says there will always be extreme snowstorms, and they may even get worse in years to come. It’s one of the paradoxes of winter warming. Even though there’s less snow staying on the ground, cities must be prepared for heavy snowfalls, even if that snow is likely to melt several times over the course of the winter.
Snow that melts, rain that freezes: the weather is more frequently yo-yoing around the freezing point. Sidewalks that used to be covered in snow in the winter are now more often caked in ice. In the past, the city spread 150 grams of salt and gravel per square metre of sidewalk approximately 15 times per year. In recent years, road crews have been salting the sidewalks as many as 25 times, and they now use 300 grams of the abrasive mix per square metre, according to Sabourin.
In Montreal, the snow cover has diminished. Dozens of centimetres of snow can still fall in a snowstorm, but that snow doesn’t stay on the ground as long as it once did. Snow now blankets the island for a full two weeks less than it did decades ago.
In Quebec City, snow is also in retreat. The city lost the equivalent of one full day with snow on the ground every four years since the 1950s.
As for Toronto, the trend for snow cover is less clear, because of the effect of the Great Lakes microclimate, as well as a lack of data from the early 1990s. However, the number of winter days with temperatures above the freezing mark have increased.
Ottawa has lost the equivalent of one full week of snow cover in recent years.
Snow that stays on the ground for several months is becoming an increasingly rare phenomenon in Calgary, as well. That city has also lost one week of snow coverage over recent decades.
Halifax has lost almost two weeks of snow cover over the past 50 years.
From his office looking out over the ski runs on the slopes of Mont Brome, Charles Désourdy can check the state of the slopes in real time. His livelihood and that of his 1,300 employees rest on those precious flakes. “Before we said that snow-making was just insurance,” says Désourdy. “Now we say that it’s our guarantee.”
Since he took over the ski resort 20 years ago, Désourdy has invested tens of millions of dollars in snow guns. “When there’s real snow, people are all excited. What I always say is that’s the icing on the cake. Because the cake itself, we make it.”
Charles Désourdy stands in front of a snow gun at the Bromont ski resort. (Thomas Christopherson/Radio-Canada)
Water from the Yamaska River is pumped through 100 kilometres of pipes that run up the mountain to the ski slopes, where it’s shot into the air and crystallizes. In November and December, skiers glided down a one- to one-and-a-half-metre base made completely of artificial snow.
Mont Brome, too, is prone to midwinter thaws or rain that hardens into a crust of ice on the slopes as soon as the temperature drops again. To deal with that problem and keep customers happy, the ski resort has developed a technique that’s unique in eastern North America. Crews groom the slopes with a harrow equipped with 12-inch discs that break up the ice and bring the soft snow underneath up to the surface. “It’s now in our DNA to work with that surface,” says Désourdy. “We have adapted to climate change.”
According to Ouranos, a Montreal-based centre for climate change research, the downhill ski season in the Eastern Townships could be 10 to 20 days shorter than it is now by 2050.
In Montreal, the daily temperature data dates back all the way to the 1870s. The data shows winter has become progressively warmer over the years.
That data shows that today, the months of December, January and February are 1.8 degrees warmer on average than they were 150 years ago.
This difference is significant. Every day that the temperature is above zero has an impact on the snow.
And the number of winter days above zero has increased noticeably in 150 years.
The same trend is apparent in Quebec City.
The phenomenon is widespread across Canada. The number of days above zero is on the rise in Toronto, as well.
Ottawa is no exception to the trend.
“There needs to be a good blanket of snow, without ice underneath, on my fields through the winter, so that my plants can still breathe,” says farmer Yanick Beauchemin. Confined to their warm barn in the winter, his cows normally eat the hay Beauchemin grows in those fields in the spring and early summer. But not this year. The farmer and his ancestors have been working the fields south of Trois-Rivières, Que., for seven generations. “For the first time, I’ve had to buy hay.”
Yanick Beauchemin tends to cattle in their barn. (Thomas Christopherson/Radio-Canada)
The snow cover on his fields just isn’t what it used to be. Winter thaws are more common. And when it rains, a layer of ice forms on top of the snow, smothering the plants beneath. “We never used to worry about winterkill. But now, we’re left to wonder if our fields won’t be dead by the spring.”
After difficult winters, followed by periods of drought, other farmers have faced the same problem, leading to a spike in the price of hay. “I can’t go without hay every year. It’s not really worth buying at $300 per tonne. Normally it’s around $150 to $200. But now there’s a shortage.” Luckily, Beauchemin also grows corn and soybeans, which yield more when the season is long and hot, allowing him to break even.
“I think that people are starting to notice that winter is changing,” says Ross Brown, the Environment Canada scientist. “And when there’s a change in the amount of snow, that triggers a whole chain of events.” Brown, who has been studying snow since the 1990s for Environment Canada, says that, for example, a drop in the amount of snow in the spring increases the risk of forest fires in the summer.
Ross Brown, left, discusses changing snow patterns with Radio-Canada’s Naël Shiab. (Thomas Christopherson/Radio-Canada)
Snow cover also acts like a mirror, reflecting 80 to 90 per cent of the sunlight. That’s known as the albedo effect, Brown says. “But when you remove that snowy surface, there is a lot more energy absorbed by the ground. This feedback ensures that the snow melts faster in the spring. The warming is accelerated.”
In his projections, Brown estimates that by 2050, the average duration of snow cover could be shortened by another 10 to 20 per cent. And even in the most optimistic of scenarios, the chance of seeing winters where snow lay thick on the ground, as it did decades ago, is almost non-existent.
Our only option left is to mitigate global warming. “When I’m at a cocktail party and people realize I’m a climatologist, their response is often depressing. They tell me that they can’t do anything in the face of climate change. It seems like they’re waiting for others to act. But it’s in our hands. We can do a lot. And it starts with individuals. It’s a choice.”
Methodology
CBC/Radio-Canada downloaded weather data from Environment Canada’s website for weather stations that have at least 40 years of historical data going up to at least 2010. Only 63 stations, all located at low altitudes, were found to have long-term data on ground snow.
Temperature data came from standardized and adjusted Environment Canada data for 337 weather stations. Only stations with at least 40 years of data going to at least 2010 were included.
Naël Shiab data journalist, Francis Lamontagne designer, Eric Larouche bureau chief, Melanie Julien bureau chief. With the collaboration of Nicolas Pham and Marc Lajoie. Translation, Matthew Lapierre and Loreen Pindera.
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