With its unprecedented record-breaking temperatures, B.C.’s recent heat wave garnered worldwide attention, especially from climatologists trying to make sense of the anomalies.
The mercury hit highs in late June that were 5 C higher than previous all-time records. BC Hydro reported a 30-per-cent higher electricity demand compared to average. And more than 700 people died over a one-week period during the scorcher — three times more than would normally have been expected.
“Typically, you’d see high temps that kind of line up with previous record highs in a way that makes intuitive sense,” said Faron Anslow, a climatologist with the Pacific Climate Impact Consortium at the University of Victoria. “The new observations weren’t lining up at all. It was kind of up in a new world.”
Anslow was an analyst for a recent scientific report produced by the World Weather Attribution initiative, a collection of international climate scientists who investigate to what extent an extreme weather event is influenced by climate change. The report concluded that the occurrence of an extreme heat wave like the one in B.C. was virtually impossible without human-caused climate change or pre-industrial revolution.
According to the report, even in the current climate, with an average global mean temperature increase of 1.2 C, the chance of this type of heat wave occurring is extremely rare. A conservative estimate would be a one-in-1,000-year event.
If carbon emissions continue as they are, B.C. could experience similar extreme heat waves once every five to 10 years by roughly 2040 with a global mean temperature increase of 2 C.
”It’s been a good warning shot for us. We got this sneak preview of what’s going to happen later in the century and now we have a lot of work to do,” Anslow said.
In the past, weather event attribution, the term used for this type of science, has been done months, sometime years later. But Anslow and the other contributors are realizing the benefit of producing these reports as soon as possible.
“If this is climate change, it really bears digging into that question as quickly as possible — to try to strike while the iron’s hot. You know, when the politicians and decision makers are broiling in their houses.”
The report also said this heat wave could have been, statistically, just very bad luck or that there is something else going on because the data is unlike anything climatologists have ever seen.
Anslow said the new all-time highs are even more concerning because they are “just so far out of line” from past records.
“Statistically, it’s like the new event is drawing from a different set of conditions,” he said. It’s like our climate has reached a new level of change.