Science

By 2080, the climate in these Canadian cities will look nothing like it does today

In a new study published in Nature Communications, researchers looked at 540 cities across Canada and the U.S. to try to show what projected temperatures in 2080 will actually feel like.

A study looked at 540 cities across Canada and the U.S.

Every summer, the City of Toronto sets up cooling centres during heat waves. (Bruce Reeve/CBC)

The average summertime temperature in Edmonton is around 15 C. It's comfortable and familiar for residents. But in 60 years, that temperature is forecast to rise by almost 5 C, more reminiscent of the climate just outside St. Paul, Minn.

That's just one of many specific geographic conclusions in a new study published in Nature Communications.

In an effort to improve climate change communication, the authors came up with an idea: what if they forecast the temperature and precipitation changes for cities in 2080, and matched them with a city that has a similar climate today?

"We wanted to answer the question: How do we communicate these expected changes in a way that's relatable to people?" said Matt Fitzpatrick, associate professor at the University of Maryland Center for Environmental Science and the study's lead author.

"The basic idea was to use this technique of climate analogue mapping, which isn't a new technique … and to do that in a comprehensive way, so we can better communicate what these changes mean."

The study looked at 540 cities, which had a cumulative total of 25 million people, across Canada and the U.S. The researchers used the average temperatures in those cities from 1960 to 1990, and then made projections using data from the Intergovernmental Panel on Climate Change (IPCC). They also included variability for each city in order to make it more accurate.

They then created a mapping application where users could choose a city, which would then link to another city that has the first city's 2080 climate outlook today, particularly in terms of precipitation and temperature. They included two scenarios: one in which global emissions stayed more or less the same, and one in which they have been reduced.

While some people may believe warmer weather is an improvement, there are serious consequences to that.

"Sure, we all think warmer will be better, but let's look at what's included with the warmth. The fact that we have Lyme disease now ... we never had that before," said Katharine Hayhoe, a Canadian climate scientist who is the director of the Climate Science Center at Texas Tech University. "We have invasive species ... the area burned by wildfires has been increasing, the length of wildfire season has been increasing. Our summer extremes, our heat waves and our heavy rain events are getting more frequent.

"So sure, it's nice to have that spring or fall day that feels like summer … but we have to realize it's a package deal, and there are a lot of parts to this package that we've been fortunate to live without for the last few decades, last few centuries. But we're getting that now."

In 2018, B.C. experienced its worse fire season on record, something that climatologists warn could be a more regular occurrence with the changing climate. (@CONAFOR/Twitter)

Fitzpatrick also noted there are economic challenges that will almost certainly come with changing climates.

"If people like a warmer climate, they're going to get it," said Fitzpatrick. "But what's going to come along with that are much higher prices for things like food, when [a changing climate] disrupts agriculture. It's going to have major impacts to other natural systems and infrastructure. We're going to pay the price in some way for what some see as beneficial warming."

Fitzpatrick noted that these city matches are not exact, because many cities' climate projections don't look like anything that exists in the present day.

"[The cities are] either becoming too warm, or their combination of temperature and precipitation isn't present today," he said.

'Global weirding'

While average temperatures, particularly in Canada, are likely to rise, that's not to say we won't still get cold spells. It will still be cold, but not like it once was.

As the climate shifts, we are seeing more extremes and weather that may seem out of place. It may be frigidly cold one day, and the next, the temperature climbs to 5 C, something that Hayhoe and other climatologists have come to refer to as "global weirding."

"It's more accurate because that's really what we're seeing," Hayhoe said. "The statistics of our weather is changing."

Paramedics on bikes provide outreach to people during a heat wave in Vancouver in June 2018. As the climate changes, cities will experience more weather extremes, climatologists warn. (Denis Dossman/CBC)

Fitzpatrick said that even for him, the study was a bit of an eye-opener.

"It really drove home the point to me that children living today are going to experience a dramatic transformation in climate over their lifetime. Those changes have already started," Fitzpatrick said, referring to the most recent climate report from  NASA and the National Oceanic and Atmospheric Administration (NOAA), which reported that the past five years have been the hottest on record.

"One thing that stood out to me was just how large of an effect that reducing emissions could have," he said. "Hopefully that is something that [gets] through to people: that decisions we make, that if we're smart about this, we can potentially fend off some of these more dramatic changes."

ABOUT THE AUTHOR

Nicole Mortillaro

Senior Science Reporter

Based in Toronto, Nicole covers all things science for CBC News. As an amateur astronomer, Nicole can be found looking up at the night sky appreciating the marvels of our universe. She is the editor of the Journal of the Royal Astronomical Society of Canada and the author of several books. In 2021, she won the Kavli Science Journalism Award from the American Association for the Advancement of Science for a Quirks and Quarks audio special on the history and future of Black people in science. You can send her story ideas at nicole.mortillaro@cbc.ca.