Friday, July 22, 2011

Heat Wave

Think it's hot out there? You obviously didn't live through the heat wave of 1936.

What's broadly regarded as the worst heat wave in North America's modern history began in late June of that year in the American southwest and seeped into Canada during the first week of July. For 13 days, from July 5 to July 17, it oppressed — and sometimes killed — Depression-era Canadians from southern Alberta to the Ontario-Quebec border.

Seventy-five years later, temperature records set during that scorching summer still stand in Ontario, Manitoba and 14 American states. "That's really still the granddaddy one of them all," says David Phillips, Environment Canada's senior climatologist.

Ottawa, situated on the periphery of the Big Heat's range, escaped its worst effects. That year in Ottawa, temperatures topped 31 C five times between July 7 and July 12, peaking at 35.6 C on July 10.

Other parts of the province were less fortunate.

Toronto endured a 10-day stretch when highs reached 30 C or more, with nary a drop of rain. For three days running, from July 8 to July 10, highs in the city topped out at the same knee-buckling temperature: 40.6 C. That's 105 Fahrenheit.

Conditions were worse in Northern Ontario. In Fort Francis, the mercury reached 42.2 C — two days running — and hit the same mark in Atikokan a day later. The readings still stand as the hottest ever recorded in the province. The plus-30 heat continued unabated for 13 excruciating days.

Even that's not the worst of it. In dust-bowl Manitoba, temperatures reached 44.4 C — 112 F — in two communities, just a trickle of sweat behind the warmest temperature ever recorded in Canada. (That came in 1937 in Saskatchewan, a furnace-like 45 C.) Those were real temperatures, too, not today's inflated "feels-like" humidex calculations.

Not only was the 1936 heat wave more intense than the current one, people had far fewer ways of escaping its sometimes deadly effects. Other than in some movie theatres and large department stores, air conditioning was unknown.

The heat wave of 1936 killed more Canadians than any other single weather event. About 780 people — mostly the elderly or infants — died because of it, as did 4,768 Americans. Nearly 600 of the Canadian deaths were in Ontario, including more than 225 in Toronto alone.

The heat contributed indirectly to the deaths of a further 400 Canadians, including weak swimmers who drowned seeking relief in the water. Others died in traffic accidents triggered by asphalt made slick and slippery by the baking sun.

"In terms of the suffering and the human loss, it will probably never be matched," says Phillips, who has written about the historic heat wave. When Phillips gives talks on weather history, people who were children during the 1936 heat wave routinely tell him they remember it as if it were yesterday. "It had such a dramatic effect on people's lives."

The unrelenting heat must have seemed apocalyptic. It warped steel girders on bridges and bent the Canadian Pacific Railway's heaviest steel rails like wire. In the Niagara Peninsula, fruit literally baked on trees. Horses hitched to bread and milk wagons dropped dead in the street. More than 200 fires burned in the tinder-dry lands between Sudbury and Thunder Bay, Ont.

"They actually pulled people off trains in northern Ontario and conscripted them to fight fires," Phillips says.

Ancient hearses were brought out of mothballs to cart away the dead. "You couldn't buy any flowers because of all the funerals," Phillips says.

Everywhere, people sought relief from the heat. They flocked to "refrigerated" theatres. "It didn't matter what was showing," says Phillips. "If it said 'cooled by refrigeration' on the marquee, that was what people went to."

At night, they abandoned their stifling houses and camped out in parks, cemeteries and waterfronts — "wherever they could get a comforting breeze," Phillips says.

Retail stores sat empty and business plummeted at taverns, because getting to one was so exhausting. But beer deliveries soared. Police waived the prohibition on topless swimming suits — for men. But officials at Queen's University in Kingston, Ont., were unmoved. They upheld the ban on wearing exposed suspenders after one overheated student doffed his coat at a university dance.

Beaches along Lake Ontario were jammed. But cruelly, the water was too cold for swimming. Offshore winds carried away any warm surface water, causing icy water to well up from below.

Americans, hoping to escape temperatures that approached 50 C, stormed the northern border, seeking relief in the world's second-coldest country. They were bitterly disappointed.

The heat finally abated about mid-July. "What saved the day, as it always does in a heat wave, was good Canadian air," Phillips says.

On July 15, the high temperature in Ottawa was a delightful 23.3 C. Though there were a few warm days later that summer, nothing close to another heat wave materialized. With the current hot weather, Canadians can only hope that history repeats itself this year.

Phillips is less than encouraging. Environment Canada's models are showing higher-than-normal temperatures in August and September, he says. "What you see is what you're going to get."