If you can’t stand the heat…just wait. As the globe warms in the years ahead, days with extreme heat are forecast to skyrocket across hundreds of U.S. cities, a new study suggests, perhaps even breaking the “heat index.”
“Our analysis shows a hotter future that’s hard to imagine today,” study co-author Kristina Dahl, a climate scientist at the Union of Concerned Scientists, said in a statement. “Nearly everywhere, people will experience more days of dangerous heat in the next few decades.”
By 2050, hundreds of U.S. cities may see an entire month each year with heat index temperatures above 100 degrees. This may be the case if nothing is done to slow down global warming.
The heat index, also known as the apparent temperature, is what the temperature feels like to the human body when relative humidity is combined with the air temperature. This is the first study to take the heat index – instead of just temperature – into account when determining the impacts of global warming, Dahl said.
The number of days per year when the heat index exceeds 100 degrees will more than double nationally, according to the study. This new research was published Tuesday in the peer-reviewed journal Environmental Research Communications.
On some days, conditions would be so extreme that they’d exceed the upper limit of the heat index, rendering it “incalculable,” the study predicts.
“We have little to no experience with ‘off-the-charts’ heat in the U.S.,” said Erika Spanger-Siegfried, lead climate analyst at the Union of Concerned Scientists and report co-author. “These conditions occur at or above a heat index of 127 degrees, depending on temperature and humidity. Exposure to conditions in that range makes it difficult for human bodies to cool themselves and could be deadly.”
Adam Kalkstein, an expert on heat at the U.S. Military Academy who was not involved in the research, told USA TODAY, “The report highlights the very real threat of (human-caused) climate change increasing the number of dangerously hot days across the United States.
“Heat is already a leading cause of weather-related mortality across the country and is frequently called a ‘silent killer’ since its impacts on human health are often underestimated,” Kalkstein said. “If the models used here are correct, this research leaves little doubt that the number of potentially dangerous days across the country will increase dramatically.”