Report: Quad Cities will be 'warmer and wetter' in future decades because of climate change

More intense flooding, drought and hotter temperatures are expected in the Quad-Cities in the coming decades as a result of climate change, according to a new report.

The assessment — Navigating Climate Challenges in the Quad Cities — was done by the National Wildlife Federation, Prairie Rivers Network and the Discovery Partners Institute at the University of Illinois System in an effort to analyze the potential impacts of climate change on the Quad-Cities through the end of the century and offer general solutions.

Climate change is a long-term change in the average weather patterns locally, regionally, and globally. Changes in Earth’s climate since the mid-20th century are driven by human activities, according to NASA, particularly fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere, raising Earth’s average surface temperature.

Average temperatures have risen about a degree in Iowa since the beginning of the 20th century, concentrated in the fall and winter.

“We found that the Quad-Cities will begin to experience more frequent and more destructive floods shortly,” said Arsum Pathak, senior adaptation specialist for the National Wildlife Federation. “Our research also shows that solutions such as permeable pavement, green roofs and stormwater gardens can significantly reduce flooding.”

Seven of the top 10 historic crests of the Mississippi River at the Rock Island gauge have occurred in the 21st century, according to the National Weather Service.

Flood simulation done by the scientists in the report show that areas close to the Mississippi River becoming more prone to river floods because of increased rainfall and higher stream flows.

The report stated places such as Cargill AgHorizons, Isle Casino Hotel Bettendorf, the Martin Luther King Center, Vibrant Arena at the MARK, and Lindsay Park Yacht Club could become susceptible to flooding as early as 2040. Water from heavy rain events could impact areas like the I-74 bridge and downstream Rock Island by 2080 or 2090.

The Quad-Cities also can expect more days reaching above 95 degrees. Under a high-emission scenario, the Quad-Cities could experience nearly two months of temperatures soaring above 95 degrees, according to the report. The area currently experiences an average of three days over 95 degrees a year.

“Our analysis suggests the Mississippi region will experience warmer and wetter conditions in the future, along with an increase in extreme precipitation events,” said Ashish Sharma, the climate and urban sustainability lead at the Discovery Partners Institute.

The risks of climate change in the Quad-Cities will more greatly impact people living and working in flood plains in Moline, East Moline, and downtown Davenport along the Mississippi and Rock rivers, the report said, and will disproportionately impact vulnerable populations, such as lower-income families, people experiencing homelessness and people with disabilities.

The report recommends "nature-based solutions" to combat the impacts of climate change on the region in the coming decades.

Those include restoring wetlands, flood plains and forests, and green spaces which would reduce the risks of flooding and flash flooding, according to the report.

Nahant Marsh, for example, in western Davenport "acts as a massive urban floodwater sponge" according to the report. It catches and filters up to 2 billion gallons of water during peak flows on the Mississippi River.

Pathak said wetlands such as Nahant Marsh will face challenges with disruptions in water balance because of more frequent droughts and flash flooding, and that impacts of climate change would be more severe without resources like Nahant.

The report also recommends increasing tree cover to shrink "heat islands" and provide more shade during periods of extreme heat.

As part of the review, researchers interviewed 30 regional natural resource professionals, conservation staff from the cities of Davenport, Moline, Rock Island, and East Moline and nonprofit and community leaders.

Researchers emphasized the findings of the assessment are not static, and there's inherent uncertainty about future changes to emission trajectories, population changes and the limitations of climate modeling.

"The findings seem like a lot, and a little scary, but this is by no way meant to be a doom and gloom report," Pathak said. "The risks are not static, they are still based on projections, emissions scenarios … the actions and policies we can act on today can change the future greenhouse gas emissions and the flooding scenarios."