Report: Climate Change Impacts Clearer In Iowa Than Much Of US

Sep 5, 2019

Iowa is seeing certain impacts of climate change impacts more clearly than much of the rest of the country, according to a new analysis for the Iowa Policy Project. The findings predict the trend of increasingly hot, wet weather in the Upper Midwest will likely continue and worsen if greenhouse gas emissions go unchecked.

Historic flooding battered both ends of the state this year, as floodwaters swamped western Iowa communities along the Missouri River and eastern Iowa communities along the Mississippi. A new report for the Iowa Policy Project finds the increased risk of these kinds of damaging natural disasters is in line with the anticipated impacts of climate change.

University of Wisconsin-Eau Claire professor James Boulter compiled the report called "An Uncertain Future for Iowa: The Outlook for Iowa Communities and Flooding as our Climate Changes." He found the Upper Midwest is clearly feeling the adverse effects of climate change, namely a marked and sustained increase in rain and snowfall. Annual precipitation has steadily increased since the 1970s, he found.

“Iowa and the Upper Midwest have a much clearer trend in annual precipitation than the whole of the contiguous U.S.,” Boulter wrote.

“This region’s average annual rainfall has been steadily rising at almost one inch per decade — a total increase of over 12 percent since the mid-1970s. Iowa’s statewide trend over the same period is still higher at 1.25 inches per decade – the largest increase across the U.S.,” the report reads.

"The effects of climate change, in both rural and urban Iowa, are becoming increasingly clear. However, these impacts are still small compared with what is projected over the next few decades under moderate and higher emission scenarios, and almost insignificant compared to those projected to the latter part of the century." - James Boulter, University of Wisconsin-Eau Claire

According to his analysis, the Midwest region is also predicted to see the greatest increase in premature deaths due to increased temperatures brought on by climate change. The region is slated to see overall average temperatures rise, as well as an increase in temperatures on the hottest days of the year.

Rural areas may be harder hit by hotter temperatures, Boulter says, especially for residents who have to work outside, or are less likely to have access to key services like healthcare, transportation or adequate shelter.

“The way this is a big impact on rural populations, of course is that, compared to cities, there’s a lot greater emphasis in rural areas on people that need to be outside to do their job. And so this becomes really problematic on extreme heat days in a different way than in an urban environment, right?” he said in an interview.

While the state saw record-breaking flooding and record-breaking precipitation this year, Boulter says it is more difficult to gauge the increased risk of flooding due to climate change, compared to rises in temperature or rainfall. A myriad of factors can play a role in how rain and snow flow through a watershed, including soil health, soil absorption and land use.

Still, according to the analysis, the Mississippi River Valley is predicted to see hydrological and atmospheric conditions that “may produce more historic-level floods," and that even the conditions that led to the 1993 floods “may become a new normal," a finding that Boulter says should be of “great concern” to Iowans.

“As I say that was a fairly…chilling…conclusion to draw,” he said in an interview.

Boulter warns that if steps are not taken to drastically cut greenhouse gas emissions to net zero by 2050, the impacts the state is currently seeing will pale in comparison to impacts felt in the latter half of the 21st century.

“The effects of climate change, in both rural and urban Iowa, are becoming increasingly clear,” the report reads. “However, these impacts are still small compared with what is projected over the next few decades under moderate and higher emission scenarios, and almost insignificant compared to those projected to the latter part of the century.”

As conditions are predicted to deteriorate, Boulter says policy-makers will likely be forced to act more broadly on climate.

“Policy responses are inevitable,” Boulter says. “The question is do we do them now in a proactive way, or do we do them much later in a reactive way, at which point they will be much more expensive and much more intrusive. That’s really the question I think that we have to ask.”