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With it finally being spring Chicago, it is natural to want to forget about the cold months that felt never ending. It is well known that Chicago is famous for its harsh winters and lake-effect cold. While this winter had its fair share of freezing temperatures, our climate is gradually changing. Winters are getting shorter and warmer.

Growing up in Chicago, DePaul alum Aliz Urquia took advantage of sledding in her neighborhood and skating in Millennium Park. Now, she said, the winter months are unpredictable.

“We don’t actually realize that we’re not getting long winters anymore,” Urquia said.

The Chicago Climate Action Plan report on climate said winter temperatures have been steadily increasing. In the last four years, the annual average winter temperature also has risen up to seven degrees Fahrenheit — and winters today are five days shorter now, compared with the years 1970 to 1997.

This past winter, Chicago experienced several temperature swings. Feb. 19 had a high of 58 degrees Fahrenheit; two days later the high was 29 degrees Fahrenheit.

Trent Ford, an Illinois state climatologist, said these changes are typical for January and February. This past winter was considered a cold winter, but the overall trend is that Chicago’s winters are warming. 

Mark Potosnak, an environmental science professor at DePaul, says it is important to understand the difference between weather and climate.

“Weather is happening today or what happened yesterday … but climate is what we expect to happen this time of year,” Potosnak said.

It takes 30 years of weather observations to establish a record showing what type of climate is expected throughout the year.

Emissions such as fossil fuels are trapping heat in our atmosphere, which contributes to a quicker rate of climate warming. In the winter, Chicago’s temperatures are dictated by the polar jet stream. The stream keeps the warm air in one direction and the cold air in another.

Potosnak said the jet stream makes it hard for the warm and cold temperatures to mix, but with climate change, he said the poles have been warming faster than the equator. That means the jet stream is weakening and causing more “waves,” which causes unpredictability.

“The more wavy that jet stream is, the more variability we’re going to have,” Ford said. 

Ford did note that varying temperatures due to the wavy jet stream do not necessarily have one specific cause. 

“It’s really hard to measure that, and it’s really hard to track that over time, let alone attributing that to climate change,” Ford said. 

He added that our perspective of cold winters is “different than it used to be.” What is considered a cold winter now would have been a warm winter half a century ago. 

Ford said this winter in Illinois was colder than the past 30-year average, but it was warmer than the 20th century average by a degree Fahrenheit.  

Urquia said it is scary to think about what the future will look like because the expected climate during each season no longer feels constant.

Climate change affects more than how much people think they need to bundle up before leaving their houses. Less cold also means a warmer Lake Michigan.

Potosnak said that climate change could change the health of Lake Michigan, a large source of drinking water, which he said would be “a huge disaster.”

Ford added that, due to the warming winters, there will be less snowfall and less snow sticking on the ground.

The rise in winter temperatures also heightens the risk of longer pest and allergy seasons, the experts said.

Urquia says the unpredictable weather changes can disrupt life and makes hers feel more chaotic.  

“I don’t even know what kind of clothes I should be having in my closet right now,” she said. 

Urquia added that she still loves that in Chicago you have the opportunity to experience what each season has to offer.

“It’s unfortunate that our future generations might not get to have that because experiencing all four seasons in Chicago is so beautiful and was one of the most amazing parts of growing up here,” she said.

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