Extreme cold and climate change: What's the deal?

In the past week, extreme cold has hit many parts of Canada, including –40 C temperatures in Manitoba, Saskatchewan, and Alberta, where the record-breaking cold led to electricity shortages.

B.C. experienced both record cold and unusually heavy snow, and much of the snow fell in parts of the province that aren't usually snowy, closing schools and downing trees and power lines. 

And yet, we've just heard that globally, the world has just set a new heat record for the hottest year, and cyclical warmth in the Pacific Ocean, called El Nino, is supposed to make it even warmer.

So what's going on?

Well, even in a warmer world extreme cold can happen. But also, scientists are examining how the two phenomena may be linked — and that by altering global systems, extreme cold might become more likely.

Here's a closer look.

Yes, confirmed Jesse Wagar, a warming preparedness meteorologist with Environment and Climate Change Canada in an interview last week. "In the wintertime we do get these really dynamic weather patterns, but I think the intensity of the systems that are moving through right now in this weather pattern is pretty unusual."

And, of course, the records for coldest temperatures recorded for a given day of the year in many places speak for themselves.

No. Global warming represents climate change — long-term trends — on a global scale, and a variety of measurements have shown a clear overall warming trend.

What's been happening in parts of Canada is weird weather — something short-term and regional.

Steve Easterbrook, the Director of the School of the Environment at U of T reminds people that, "Climate change does not remove winter so we're always going to have winters. What climate change does is it just shifts all those temperatures up a little on average".

"No single weather event can prove or disprove global warming," explained Matthew Barlow, a professor in the Environmental, Earth and Atmospheric Science Department at the University of Massachusetts Lowell in a recent article in The Conversation.

Megan Kirchmeier-Young is a research scientist with Environment and Climate Change Canada who uses climate models to figure out whether certain extreme weather events can be linked to climate change.

She noted that even as climate change warms the Earth, there are still seasons and natural variability in day-to-day temperatures. "We still have very cold days."