Happy Birthday, Celsius! Canada marks 50 years of metric-Imperial measurements

A Toronto shopper studies metric packaging on pet food in Toronto, Jan. 10, 1976. THE CANADIAN PRESS/staff

EDMONTON — Happy Birthday, Celsius!

Environment Canada's use of Celsius turns 50 years old in 2025.

It was the catalyst of a lengthy national metric conversion that abruptly ended a decade after it began.

The result is seen and felt every day. Canadians wear clothes measured in inches and buy gas by the litre. They drink from millilitre beer cans and step on bathroom scales in pounds. They eat cereal by the gram and sub sandwiches by the foot.

Give someone an inch, and they'll take a kilometre.

A bone-chilling April Fools' Day in 1975 marked the first time Canadians used Celsius to measure weather temperature.

"We were the guinea pig," said David Phillips with Environment and Climate Change Canada. He joined the weather service seven years before the Celsius switch.

They tried to get the word out, he said.

"I remember that first little flyer that (said), 'It's no April Fools' joke."

But some tuning into TV and radio that day might not have got the memo.

In a world where water freezes at 32 F, Canadians failing to convert Fahrenheit to Celsius woke up aghast at forecasts ranging from -2 C in Toronto to -27 C in Edmonton.

"To hell with the weather maps and figures in Celsius," wrote one senior in a letter to the London Free Press.

The switch kicked in just as a severe storm hit the Maritimes, and some felt Celsius was to blame.

"Since those experts changed from the old Fahrenheit thermometers, the weather's been lousy," an angry reader told The Bridgewater Bulletin in Nova Scotia.

Most Canadian media used both units for awhile. Some seniors near the Canada-U.S. border opted for American TV and radio for Fahrenheit-focused forecasts. By 1977, all Canadian weather reports used metric measurements.

"The strategy of going to the weather service first and getting them involved really paid off," said Phillips.

One month into the switch, the head of Canada's Metric Commission, Stevenson Gossage, said negative reactions were "dying down."

Metric appeared poised to stay. Or was it?

Then-prime minister Pierre Trudeau's Liberal government formed the Metric Commission in 1971, after industries called on Canada to ditch Imperial measures. Along with Celsius, the commission called for road signs to use kilometres by 1977 and gas pumps to measure in litres by 1979.

In the U.S., then-president Gerald Ford enacted similar legislation, but conversion was voluntary.

It got political -- and nasty.

More than three dozen Conservative members of Parliament, including Bill Domm of Peterborough, Ont., championed petitions with thousands of signatures and opened a "freedom to measure" gas bar that sold fuel by the gallon or the litre.

Domm said they were ready to go to jail over the issue.

In 1983, an Air Canada flight dubbed the "Gimli Glider" made an emergency landing at a Manitoba airfield after running out of fuel. Faulty metric-Imperial conversion was cited as a factor.

Gossage died in January 2001. Jonathan Gossage said his father felt the transition to metric was important for Canada, as the Imperial system an "unnecessary bottleneck" in international trade.

"My take on it always was that it was the right way to go," the 87-year-old said in a phone interview from Ottawa.

He also said he felt those naysayers were "short-sighted."

"If the conversion was going to be easy for you, you had to be good at mental arithmetic. If you weren't good at mental arithmetic, it was a much more difficult proposition."

Gossage said the transition has worked out well, as younger generations are raised with metric being their primary unit of measurement. However, there are still times when he has to use Imperial.

By the early '80s, then-U.S. president Ronald Reagan torpedoed Ford's Metric Act and the Metric Board as a cost-cutting measure. Former prime minister Brian Mulroney and his Conservative government followed suit, disbanding the metric commission and making the switchover voluntary.

In the end, the metric revolution resulted in a half-built house.

Edmonton quilter Jody Groenendyk uses Imperial regularly because it's the industry standard, and it's easier to divide.

"(Imperial) is just so familiar," she said. "Most of the rulers that we're able to obtain are in Imperial. Some of them do have centimetres on them as well, but I would say a lot of them don't."

Liam Brownrigg of Union Wood Co. in Vancouver said much of the material he buys is measured in Imperial.

One of his co-workers, who once worked in Quebec, told him people in that province primarily use metric measurements. He doesn't see people rushing to change the mixed system any time soon.

"If ever a client gives me a dimension in centimetres or something, the first thing I do is just convert it," he said.

If Canada brought back mandatory metrication, Brownrigg said switching would be a pain but people would get used to it. Groenendyk also said it would be challenging to adapt.

"Wouldn't be easy, but it would be doable," she said.

This report by The Canadian Press was first published Dec. 31, 2024.

With files from Jack Farrell in Edmonton