Daily high and low temperatures are recorded in a Stevenson Screen, a sun-shielding ventilated compartment invented by Thomas Stevenson, father of Robert Louis Stevenson. Photo: Liz Clayton

Observing Toronto's Weather

(National Post, 13 Aug 2003)

by Liz Clayton

For the past 49 years, Alan Channon has stepped into his yard approximately every twelve hours, rain or shine, to determine, well, whether it was rain or shine. As a volunteer weather observer for Environment Canada, Channon is expected to report the daily high and low temperatures, as well as the amount of any precipitation.

Channon began his observations the summer before he entered grade 12, when a friend of his mentioned that the Meteorological Division — then a subset of the Department of Transport — was looking for volunteers.

“I was too shy to call, so my dad called and said he had a son that was very interested in the weather, and a few days later there was a big crate for me up in the express office,” says Channon.

Channon’s crate contained a set of instruments and gauges which he set up in his King Township yard. When he and his mother moved to Richmond Hill in 1958, the instruments came with him, making him the first volunteer weather observer in Richmond Hill — and one in a long tradition of weather observation throughout the GTA.

Toronto has been the site of meteorological observations — volunteer and official — since the early 1800s, when it the British government decided that weather and climactic obesrvatories ought to be established throughout the British Empire. An officer of the Department of Ordnance was dispatched to Canada to establish a national meteorological observation headquarters in Montreal.

As luck would have it, Montreal had precisely enough magnetic bedrock to skew the chance of any reliable readings — not only were some of the instruments magnetic, the military was interested in how the variaton of the earth’s magnetic fields affected weather. Montreal would simply not do, and the site was instead built in Toronto.

The first weather station was built temporarily at the Bathurst Street Barracks, on the lands we now know as Old Fort York, where regular observations began to be taken on January 1, 1840. In September of that same year, observations moved to a new facility, the Toronto Magnetic and Meteorological Observatory, a log cabin built on the less muddy grounds of King’s College.

By the 1850s, a new stone observatory was built in its place — and still stands today behind Hart House, albeit without the weather instruments, which were packed up and moved a few times until 1909, when the new Meteorological Service Headquarters was established at 315 Bloor Street W.

The move came about after after much complaining by the then director of the Meteorological Service, Sir Frederic Stupart, who lamented, “the encroachments of the University on our property have ruined the old site as a suitable exposure for meteorological instruments.”

Indeed, accurately measuring the weather requires a certain amount of open space — something even more difficult to come by in downtown Toronto now than it was in 1909.

Bryan Smith, Supervisor of Environment Canada’s Ontario Climate Centre, says that because of the density of buildings in Toronto, they don’t assign many volunteer spotters downtown. “You do need some open space,” says Smith. “You can’t put a rain gauge beside a tree or next to your garage.”

Smith, who deals directly with the more than 150 volunteer observers in the GTA, says that many of the volunteers are people that are just “interested in the weather.”

“They’ve come to us,” he says.

Though forecasting technology has grown by leaps and bounds, the nuts and bolts of taking simple observations haven’t changed much in the five decades Channon has been doing it.

“It’s just gone from Fahrenheit to Celsius,” says Channon. “And the rain gauge has changed. It used to be a nice little copper rain gauge, now it’s a big plastic one. When it snows it’s still just a ruler, that’s the high-tech way of doing it.”

While simply recording weather that’s already happened may seem like yesterday’s news, those observations play a vital role role in predicting the weather of tomorrow.

“You can’t do forecast without the observation,” says meteorologist Harold Hosein. “The observations give you the actual conditions on the ground, and then twice a day, at 12 hour intervals, there are observations made using balloons that sample the atmosphere. It’s the combination between the two actuals on the ground and the atmposphere above you that allow you to produce a forecast.”

Though observers like Channon continue to be useful to Environment Canada for collecting outlying data, the organization’s official weather stations are now largely automated. Human readings, can be more reliable than automated readings, are still taken at Pearson International and Buttonville airports, however they are fully automated at Toronto Island Airport, Even the observation site at the University of Toronto — now located behind an innocuous fence on the grounds of Trinity College — is unmanned.

Observations at the Environment Canada headquarters themselves, which in 1971 vacated the Bloor Street building for a newer facility in Downsview, are still done by hand.

At the Downsview site, a modest field of weather equipment sits behind a thriving natural garden tucked quietly off of Dufferin St. Anemometers, spinning cups that measure wind speed, twist in the air as Smith conducts a small tour of the observation station’s instruments. Rain is collected in large cylinders which reflect light to diminish the water’s evaporation. A special bell-shaped object measures snowfall. More than a dozen white-slatted boxes stand on large posts every few feet, shielding thermometers from direct sunlight while allowing the air to pass through.

And what’s that strange hole in the ground for, near the bell-shaped snow gauge?

“Oh,” says Smith. “That’s where the groundhog lives.”