‘Extreme heat belt’ will include Southwest Ohio, study says

Area in 30 years expected to experience heat index above 125 degrees.

Southwest Ohio is the only region in the state that is part of an emerging “extreme heat belt” that is expected to experience days with a heat index above 125 degrees in 30 years, according to a new study.

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Temperatures at or above the National Weather Service’s “extreme danger” heat category — when the “feels like” temperature is 125 degrees or higher — are expected to affect 8 million people this year. In 30 years, that number is projected to increase to more than 107 million, or 13 times more people, according to the study published Monday.

Researchers from the First Street Foundation, a research and technology nonprofit working to define America’s climate risk, looked at how the frequency, duration and intensity of extremely hot days will expand over the next three decades.

‘The results will be dire’

“Increasing temperatures are broadly discussed as averages, but the focus should be on the extension of the extreme tail events expected in a given year,” said Matthew Eby, First Street founder and CEO. “We need to be prepared for the inevitable, that a quarter of the country will soon fall inside the ‘extreme heat belt’ with temperatures exceeding 125 degrees Fahrenheit, and the results will be dire.”

All areas of Ohio will see higher temperatures over the next 30 years, but the climate research group’s model only places seven Ohio counties inside the heat belt: Butler, Clermont, Hamilton, Miami, Montgomery, Preble and Warren. They especially will be vulnerable to what is now considered an unheard-of heat index, which is a measure of how the air feels with the temperature and humidity combined.

“It’s not something that just came up. It’s been happening globally, and it’s going to start affecting us locally here,” said University of Dayton geologist Umesh Haritashya who researches how climate change affects the environment. “The changes that we always think of happening to the coastal communities, to places like Texas, those changes are going to happen here.”

Credit: First Street Foundation

Credit: First Street Foundation

The more than 1,000 counties that make up the extreme heat belt that stretches from northern Texas and Louisiana to Illinois, Indiana and even into Wisconsin are concentrated in the middle of the country, “in areas where there are no coastal influences to mitigate extreme temperatures,” the report stated.

‘Challenging to go out’

The increase in extreme heat will affect everything from personal health to electricity costs to possibly infrastructure and transportation. Common building materials such as steel and cement absorb heat easily. In extreme heat, roads and airport runways can buckle, railroad tracks can warp, and bridge joints can swell, the study noted. Also, increased air conditioning use may strain energy grids.

“It’s not all gloom and doom,” Haritashya said. “Definitely there will be days where it will be challenging to go out.”

Policymakers generally are focused on the short term, he said. But the area will need to adapt, and start making preparations now to make sure the electric grid is robust to avoid the problems like those facing Texas and Arizona. Homes should be in good repair and well insulated to withstand extreme heat to avoid a future of rolling blackouts and brownouts as extreme heat increases in frequency, intensity and duration over the next 30 years.

“That’s where we probably will face our biggest challenge,” Haritashya said.

Bob Brecha, professor of sustainability and director of the Hanley Sustainability Institute, said local residents and leaders shouldn’t be complacent even though the study looks at temperature projections three decades from now.

“These changes don’t occur suddenly, but rather, they ramp up gradually. It may not be as critical for us in Southwest Ohio to look at that highest category of 125F, but even the next category of 100F is important for things like people who have to work outdoors, those who can’t afford air conditioning and those with health issues for whom extreme heat is very uncomfortable at the least,” Brecha said.

Unfortunately, those most affected will be people living in low-income neighborhoods. The housing stock tends to be older and closer together, which traps heat, and there are fewer trees and green spaces.

Extreme weather events

Extreme heat can cause flooding risks to go up, especially flash floods, and also will make the summer weather last longer. It’s unknown at this point whether that in turn will mean a shorter, intense winter or a shorter and mild winter, Haritashya said.

“Extreme heat can cause other extreme weather events, and we need to prepare for that,” he said.

Reduce CO² emissions

“On a global scale, the clear message for decades has been that we need to reduce our carbon dioxide emissions that come from burning fossil fuels,” Brecha said.

The study placed Ohio among the top five states — behind Texas, Florida and California and ahead of Missouri — with the biggest cooling demand-related spike in carbon dioxide emissions between now and 2053.

“This indicates a need to evaluate the design of the energy systems for the increases in relative heat exposure to the area over the next 30 years,” the study reported.

Cooling costs for 2023 in Ohio will be about $571.3 million, and those will be a projected $686.7 million in 30 years, an increase of $115.5 million.

Ohio’s cooling consumption estimated for 2023 is 4,500.1 gigawatt hours, which would increase to 5,409.6 GWh in 2053. Emissions of 5,499.1 million pounds of carbon dioxide would increase to 6,610.5 pounds in 2053 due to AC use, according to the report.

Individuals do not have the power to influence the transition to renewable energy across the world that contributes to climate change, but Brecha said local residents can take steps in their own communities.

“If you have a home, plant trees to keep your local area cooler. Encourage city officials where you live to increase park areas and shaded areas in their towns,” he said. “We all know that a wide open, paved area feels much hotter than a shady area even if they are only 50 feet apart. Shaded city areas are better off than open spaces.”

Temperatures are projected to increase by at least 2.5 degrees over the next 30 years.

The area now has about seven days a year that spark high heat advisories or warnings. The study says that figure could grow to 19 days for Southwest Ohio by 2053.

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