This year, Chicago saw the coldest and snowiest start to winter in years, reaching a windchill between negative 30 and negative 40 degrees Fahrenheit on Friday, January 23rd.
As snow piled on Deering Lawn, classes moved to Zoom and students bundled up in their dorms, global warming seemed like a distant thought. And if you were fighting a thick layer of driveway snow with a shovel, it might’ve even seemed like a comforting thought.
But climate change is warming winters faster than any other season, and Chicago is no exception.
This winter saw a sudden turn in the past couple weeks, with temperatures consistently above freezing. The snowmen are melting into sidewalk puddles, and stretches of brown, soggy lawns are peeking out. So what can we expect from future Chicago winters?
[MUSIC: “Evening Snowfall – Soft Winter Piano Music”]
[ANN SINCLAIR]: The trend is that on average winters are getting warmer, or milder. When we see this really cold spell or this winter storm that’s happening, that’s sort of natural variability in the climate system, but it doesn’t mean that the trend doesn’t exist.
That’s Ann Sinclair, a PhD candidate in the Department of Earth, Environmental and Planetary Sciences at Northwestern University. She says short-term temperature drops shouldn’t be mistaken as markers for general climate trends.
Aaron Packman, a professor of Civil and Environmental Engineering at Northwestern University, and the co-director of the Northwestern Center for Water, agrees.
[AARON PACKMAN]: Climate change is a lot about variability, so the variability is increasing greatly. That means we see more heat waves, we also see more cold waves.
Midwestern winters have changed dramatically over the last decade.
Finley Hay-Chapman is a postdoctoral researcher in the Climate Change Research Group at Northwestern. He grew up in Madison, Wisconsin.
[FINLEY HAY-CHAPMAN]: I’ve definitely noticed growing up, and especially in the 2010s and onward, winter is getting a lot warmer and more muddy and gross and wet, as opposed to cold and snowy. I would say.
Packman says precipitation patterns have changed.
[PACKMAN]: We’ve had a number of rainstorms. This is particularly challenging when there’s a lot of snow accumulated, you have rain on top of it. It’s called a rain on snow event, and we’ve had a number of them in the winter that have caused a lot of flooding. By 2018, we had like the first big rain on snow event, just a big warm rainstorm in January. So that had basically never happened before, and now we’ve had 3 or 4 of those in the last 10 years.
Cold snaps like this year’s are also a product of global warming.
The jet stream is an air current that circles the Earth, cutting off Arctic air from the air below. It forms because of extreme temperature differences between the Arctic and the tropics. This creates energy that turns into momentum. But with climate change, the Arctic has been warming faster than the tropics — essentially, the temperature gap is shrinking. Hay-Chapman says that as the jet stream grows weaker, it can cause more polar vortex intrusions.
[HAY-CHAPMAN]: The reason that we have these cold snaps is that jet stream gets really weak, and instead of being a long straight river of air, it gets all wobbly. Eventually, if it gets wavy enough, you can have one of those dips kind of close off from the wave, and you get this drop of cold air that goes down. That happens when the jet stream is unstable, and we know that climate change is causing that instability, and so we might even see, even if on average, it’s gonna be warmer in the winter, over the whole winter, we might see more of these like small short-term cold snaps because of climate change.
As a city familiar with extreme weather, Chicago is relatively well-equipped for these freezing spells.
[PACKMAN]: The city of Chicago and other municipalities have programs for emergency response, for heat waves and cold waves. So you can look up these resources in the City of Chicago Department of Emergency Management. Part of it is just basic sensible advice in terms of how to protect yourself from the cold when you’re outside, but the other part of it is warming shelters or other places that people can go if they don’t have sufficient heat at home.
Still, not all neighborhoods have the same resources. Hay-Chapman is part of a group that’s working on a tool to determine heat vulnerability to inform climate policy. He says these urban planning disparities are often in lower-income communities of color.
[HAY-CHAPMAN]: You can sort of think of neighborhoods as little microclimates, and how they’re built really has a large impact on how the people who live there feel the weather. When it snows outside, and the snow sticks on the ground, man-made structures get a lot colder. And the snow can stick around and stay in areas that have a lot of concrete, as opposed to areas that have a lot of, like, trees, soil, grassy environments, that snow can melt a lot easier.
He says that as temperatures go above freezing, rain — not snow — will become our primary winter challenge.
[HAY-CHAPMAN]: That can cause issues for flooding in the city, especially in the winter when the ground is really hard and cold, because the water isn’t able to sink into the ground as much. And so there’s a lot of neighborhoods on the South Side in Chicago that are really vulnerable to flooding that could be impacted.
Sinclair says there are some strategies that can help the city deal with flooding.
[SINCLAIR]: We have a lot ofnon-porous paved land surface. In general what we expect with precipitation and climate change is that the extremes are gonna become more extreme. So you’re dumping a lot of water on a generally not porous land surface, and that is going to lead to flooding. You can pave with certain materials that are better at absorbing water, and we can kind of create infrastructure for floodwater control.
She says climate change is intertwined with social justice.
[SINCLAIR]: The folks who are houseless, for example, are going to be the most impacted by the extreme heat and the extreme cold. And so the best way to fix that is to create a system where nobody is living on the street. Or, if people have resources that they can use, people have places they can go to seek shelter when it’s really hot or really cold.
For many people, thinking about a changing climate can cause stress or grief. Sinclair has some tools that may help.
[SINCLAIR]: I read a lot of poetry. It’s good to remember, especially as a natural scientist, that the world’s really beautiful, both in terms of the human world and also our natural environment.
Reading poetry offers Sinclair a fresh perspective when she needs it.
[SINCLAIR]: There’s a lot of magic and beauty out there that makes it worth fighting for. It makes it worth getting up every day and looking at my silly little code.
She also encourages open dialogue about feelings related to the climate.
[SINCLAIR]: I think there are a lot of people who are sort of secretly dealing with grief around climate change. And because it’s become a politicized issue, I think that a lot of folks don’t feel the ability to talk about it. Like any form of grief, we need to be able to feel it. And so, talking about it and finding ways to be outside. You know, we live in a beautiful city. Sometimes I go to the lake and I’m like, wow, it’s crazy that I live here. You know, enjoying a sunset. Like, I know that sounds silly, but I do think it’s worth it.
Above all, it can be empowering to know we have some power to help combat the consequences of climate change.
For policy-makers, Hay-Chapman has some ideas.
[HAY-CHAPMAN]: We really need to get resources to our most vulnerable communities, however we can. A very simple way to do that, at least from the policy side, would just be subsidizing air conditioning units for low income housing. Or, a lot of the people who are most vulnerable, are lower income and happen to be renters. So, another route the city could go with this is, requiring landlords to have air conditioning units, and putting the onus on them to provide for their residents. And so you could do that with a simple city ordinance.
Packman says infrastructure adjustments — like green roofs or tree planting — may help.
[PACKMAN]: I think the strategy now is not to rely as much on very large and expensive centralized infrastructure, but to use that as sort of a core capability and figure out how to build something more flexible on top of it. That’s also why there’s a lot of interest in green infrastructure because you can put them in at a smaller scale, cheaper and through government-private partnership, as opposed to the old strategy where we would build a big sewer system or something that is very expensive, hard to maintain or change, and just difficult to operate long term.
On the individual level, there are some things we can do.
[PACKMAN]: Vote with your dollars. Spend money on products that are more sustainable, on energy sources that are more renewable, and also encourage companies and politicians to do the same.
[SINCLAIR]: It’s not this kind of black and white all or nothing thing: it’s every little change that we can make is going to make a huge difference for somebody or some community out there.
[HAY-CHAPMAN]: Try to organize and provide for your communities. Go show up to your local alderperson meetings, and try to talk to the issues you think are important in your community, like, planting trees, or improving access to cooling. I also am a big advocate for community mutual aid, so making sure that you know your community members, especially the ones you think might be vulnerable during heat waves or cold snaps. Like the single old lady that lives down the block, just try to check in on her when it’s super hot outside, stuff like that.
In the middle of long winters like this year’s, it’s nice to remember the memories the season has given us.
Packman remembers enjoying the snow with his daughter.
[PACKMAN]: I’ve been here 25 years, and the first year I was here, there was record snowfall. It just started snowing in November and December, it kept piling up, and there was like several feet, a meter of snow by the end of December, and it just stayed on the ground until March.
I had a toddler at the time, so we built kind of a little slalom run thing and I would pull her around in the backyard on her sled, and you could do that for months.
Hay-Chapman loves the city’s ice rink.
[HAY-CHAPMAN]: It’s called the Daley Ice Ribbon. That’s been one of my favorite parts of Chicago winters.
And Sinclair has found comfort in the season.
[SINCLAIR]: When we had the first snowstorm this year, I had an amazing Saturday where I didn’t have to leave the house at all. That never happens, you know. So I stayed inside, I was listening to an audiobook, and I just watched the snow all day. I was decorating my apartment for Christmas, and it just, it felt really cozy.
So stay warm this winter, and enjoy all that it has to offer. For WNUR News, I’m Supriya Akella.
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