Will we see more extreme weather in Iowa? Here’s what experts say

Hail. Derechos. Ice storms. Tornadoes. Floods. Droughts.

All are examples of extreme weather in Iowa. Over time, these events have grown more variable, more frequent — and, sometimes, even more extreme and damaging, said experts last week during The Gazette’s Iowa Ideas virtual conference.

During an hourlong panel Friday, five experts discussed the widespread impacts of extreme weather in Iowa, from the state’s agriculture to its power grid. Local infrastructure wasn’t designed for today’s changing climate, they said. Communities need to continue adapting.

“We can’t wait another 20 years,” said Gabriele Villarini, a University of Iowa professor who researcher extreme events. “Those are things that we need to decide today or yesterday.”

Ag impacts ‘really hard to recover from’

Weather’s impacts to Iowa crops aren’t new, said Mark Licht, an Iowa State University extension cropping systems specialist who studies adaptation to weather events. But these impacts have started covering more territory. For example, the 2020 derecho wiped out millions of acres of corn and soybean, he said.

“When we think of the severe events, I tend to think of them happening on a little bit of a broader scale,” he said. “And those are really hard to recover from.”.

Storm damage harms crops, but changing climate conditions also change agricultural production needs. Increased rainfall in the winter and spring can sweep away topsoil during times of tilling, and the resulting runoff leaving nutrients in Iowa waterways. Shifting freeze dates impact growing seasons for tree fruits and perennial crops.

Resources, like crop insurance policies and soil health initiatives, help farmers recover from weather impacts in the short term. But confronting longer-term weather shifts — like more precipitation in the winter and spring — requires a change in practice.

Planting dates may need to shift to offset these changing patterns, Licht said. The crop industry also is looking for more avenues of resilient production, such as adding different crops within rotations or increasing amounts of no-tillage systems.

“Right now, I think we're playing the game of, ‘When do we really need to make that change?’” he said. “(It’s) adapting year by year versus thinking long-term at how quickly can we do this to help prepare us.”

Resilient energy grid

Throughout extreme weather events, utilities’ top priority is keeping the lights on for customers. Aaron Graber, an engineer for transmission company ITC Holdings, said he and others work lots of long hours restoring fallen power lines after bad storms — particularly following ice storms and derechos.

The power grid continuously is being fortified to be more resilient against extreme weather, Graber said. Facilities are designed to endure extreme winds and ice loads, and most infrastructure avoids flood plains. Even though some power lines may go down in storms, utilities try to replace them with stronger structures.

The challenge with the utility industry, though, is that much of the infrastructure is old, Graber said. With inflation and rising energy costs, utilities and their customers can’t afford to wholly update all structures to withstand climate projections. But utilities are working together to come up with an industry standard for resiliency.

“(The grid) is designed for extreme weather events, but we understand, in certain circumstances, it will fail,” Graber said. “We're working to determine how we best approach it to keep improving that performance.”

Keeping areas functioning — and, more importantly, safe — after extreme weather will take more than keeping the grid running.

Bolstering resilience efforts within communities in between events can help them be more prepared, said Linn County sustainability director Tamara Marcus. That includes prioritizing populations that are often disproportionately impacted by extreme weather.

There also needs to be coordinated efforts across entities responding to disasters, she said, from governments to utilities to nonprofits. Properly interconnected systems and communication avenues will help communities better recover from severe events.

What can we expect?

Climate modeling helps researchers project decades of climate conditions — but not all models are created equal, Villarini said. Each has its own strengths and weaknesses.

But as new generations of models are produced, their performance improves. Researchers can rely on an ensemble of models to ensure their projections are as accurate as possible.

“I think that if we do our due diligence, we can build our confidence in (models’) suitability, and then hopefully convince the public … that they're a good resource for a future for which obviously we don't have observations,” Villarini said.

From what researchers have gleaned from these projections, larger weather events will grow more frequent — and often be intertwined with each other, said Dennis Todey, who directs the U.S. Department of Agriculture’s Midwest Climate Hub in Ames.

Precipitation patterns, although difficult to project with certainty, are expected to shift from summers to winter and spring seasons. Higher and more frequent heat events are forecast for Iowa as well, which would especially strain communities recovering from derecho tree loss. More subtle climate changes are also expected, Licht said, such as increased nighttime temperatures and warmer springs — which will impact Iowa’s crops.

Should Iowans expect extreme weather events to become even more severe?

“I don’t think the science is well-versed on that one yet,” Todey said. “But certainly, the changes in temperature and precipitation are going to cause some differences in what we’re seeing in the central U.S.”

Comments: (319) 398-8370; brittney.miller@thegazette.com