Global cooling, everywhere
By STEPHEN STRAUSS
From Wednesday's Globe and Mail
For Canadians who have spent the summer asking where summer has gone, new satellite observations show we're not alone.
According to an analysis by scientists at the University of Alabama at Huntsville, July was the coldest worldwide since 1992. That year's cool spell was precipitated by the eruption of the Philippine volcano Pinatubo, which spewed 20 to 30 million tonnes of sunlight-deflecting dust into the atmosphere.
But scientists don't know why the Earth's thermostat has dropped this year.
In the Northern Hemisphere, July's temperatures were below the 20-year average by .14 degrees Celsius and in the Southern Hemisphere by .29 degrees. Both the tropics and Antarctica showed marked coolness.
The July weather tracks a drop in average worldwide temperature that has been going on since March, said John Christy, a professor of atmospheric science at the Alabama university.
What is not clear is whether a single physical phenomenon is responsible for the downward trend.
"There haven't been any new volcanoes or anything like that," Prof. Christy said, "so I think we just have to chalk this up to the natural variability of the system. Just as the hottest year in the past 20 years has to occur sometimes, the coolest summer in the last 10 years also has to occur sometimes."
Rick Walls, a meteorologist at Environment Canada in Winnipeg, said: "In the eastern Prairies it looks like it is going to be the coldest summer on record since data started being collected in the 19th century."
How cold did it get? In Saskatoon on July 29, the overnight low was .07 degrees, breaking weather records that had been started in 1892. In Winnipeg on July 23, the overnight low was three degrees, the lowest recorded since 1872.
It was the cold in the Prairies that may have been the most impressive. For May through mid-August, temperatures were on average three degrees below normal, beating records that go back to 1872.
But Dave Phillips, chief meteorologist for Environment Canada, pointed out that the cold wasn't just slightly beating the past. In weather terms it completely eclipsed lows of 14.2 C which were recorded in 1883 and 1907.
"A half of a degree average difference is like somebody in the hundred-metre dash in the Olympics not beating the former world record by the usual tenths of a second, but by a full second," he said. "It is really quite startling." end new
July hasn't been marked by bizarre weather, Mr. Phillips said. "We haven't had any frosts or freak snowfalls in July. The central fact of the whole summer has not been that it has been so cold; it is just that it hasn't been so hot."
However, a portion of coastal British Columbia has been experiencing one of its hottest summers on record, he said, noting that Victoria and Vancouver had their second-warmest July on record.
In Victoria, July was the second warmest in records that go back to 1898, and a similar record-setting month was experienced in Vancouver, where temperatures were on average 2.2 degrees above the monthly average.
The unseasonable temperatures may have an unexpected positive health spinoff: Less mosquito-borne West Nile virus has been seen across the country, he said. "The cool weather means there are less mosquitoes."
But some businesses that depend on fair weather are feeling the pinch. "I was expecting to do better," said Maria Gilipo, marketing and finance manager for Sicilian Ice Cream Company, an old-fashioned ice-cream parlour in Toronto. "It's been a lousy summer. When it's cloudy, gloomy and rainy, people don't come to visit us as often."
At the 105-room Bangor Lodge on Ontario's Lake Muskoka, bookings haven't dropped but the guests have adapted to Mother Nature's whims.
"A lot more people are in the heated pool this year than in the lake," staff member Michelle Smith said. "We have three weeks of the summer left, and we're certainly hoping the weather warms up."
"A lot more people have been cancelling or rescheduling their reservations at the last second," said Thom Lillie, assistant manager of the Whispering Pines Campground in Bracebridge, Muskoka, which can accommodate up to 600 campers. "People are keeping a close eye on the weather forecasts."
While Canadians who have taken themselves off to the beach or the cottage may feel a little cheated by the cool weather, a super-hot summer isn't everyone's idea of paradise. "Here in Alabama we have been very grateful for a cool summer," Prof. Christy said.
And for those who worry that the cool July might herald a long-term trend, the scientists have good news: Preliminary data for August suggest that the downward trend will be reversed this month.
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