A changing Central Illinois climate means more extreme rainfall, agricultural woes, and an encroachment of ticks
The Illinois climate is getting warmer and wetter over time.
That's perhaps an oversimplification of how climate change is impacting the Land of Lincoln. A 2021 assessment by the Nature Conservancy found average daily temperatures have increased by 1 to 2 degrees Fahrenheit over the past 120 years. Precipitation has increased by 5 to 20%, with the number of days with at least 2 inches of rain increasing by 40% over the past 120 years.
Trent Ford is the Illinois State Climatologist. He said while an increase of 1 to 2 degrees might not sound like a huge shift on its surface, it represents a big change in the number and scale of extreme conditions.
"Even that degree, a degree and a half Fahrenheit increase can mean let's say 20, 30, 40%, more precipitation intensity, or heavy rainfall events, for example," he said. "Each have their own impacts, of course, for flooding, and agriculture and urban planning. That degree, a degree and a half Fahrenheit warming could mean between 10 and 20 additional days over 95 degrees in the summertime for Peoria."
Ford said a heavy rainfall event in the Peoria area in July 2020 illustrates some of the larger challenges going forward, particularly in vulnerable areas outside the traditional floodplains. The region received five to six inches of rain over the span of a few hours.
"That's not enough rain over a small period of time over a short period of time to flood the Illinois River. But instead what we see is neighborhoods well off of the river flooded, because the stormwater drainage systems just can't handle that. They're not built for that," he said.
When Ford tours around the state to talk about climate change, he said more intensive rainfall is often one of the first things people say they're noticing.
"There's still, you know, areas, corners, where the conversation is trying to convince somebody that climate change is real, but anymore, a lot of the conversation is around, okay, great. It's going on. What do we do with it? How do we make these changes?" he said.
A warming climate also has impacts for agriculture, an Illinois powerhouse industry. Ford said climate change increases humidity, which makes staple crops like corn more vulnerable to fungal diseases like tar spot. Management of insect pests and weeds also becomes more difficult. Rainier days means a greater risk of heavy machinery causing the soil to compact, which creates a headache for farmers. More rainfall also means more nutrient runoff into Illinois waterways. That creates not only ecological problems for rivers and the Gulf of Mexico, but also an economic hit for farmers watching expensive fertilizer and valuable topsoil washed off their fields.
Ford said when he's talking about adapting agricultural practices to a changing climate, he also talks about the economic and practical reasons to do so.
"There are many reasons to do that, that have nothing to do with climate change. Climate change is just yet another reason to do that kind of puts it in the forefront. So that's how I like to frame it when we're thinking about how to adapt to climate change, is that some of these decisions that people are making, it may just changed the calculus of either the economic importance of doing that, or, or the environmental importance, or so on," Ford said.
Climate change also leads to a changing ecosystem. Ford said background warming during the winter allows a variety of non-native flora and fauna to begin making their way into Illinois.
Some of those, like the occasional armadillo sightings in Central Illinois, grab headlines. Others, like the encroachment of the Gulf Coast tick, don't necessarily garner as much attention, but may pose a greater risk, Ford said. The non-native tick is a carrier of a form of spotted fever which can be transmitted to humans.
"When we think about fewer nights below freezing in the fall, the winter, and the spring here in the Peoria area, it means more activity for ticks," Ford said. "Just a higher chance of people coming in contact with them, and then the public health ramifications of that."
Ford said individual action to combat climate change is important, but limited. He said systemic change is required, but people can still make a difference through keeping climate change at the forefront of the conversation through local community groups and activism.
"People are sitting back hearing these kind of negative stories about climate change can be really down, gloom and doom," he said. "And so those sorts of individual actions are probably the most important way to sort of make sure that we're, we're not vulnerable to these sorts of impacts."