Climate Change Could Mean More Dangerously Hot Days in Dallas, Report Suggests

Credit Wikimedia Commons

Credit Wikimedia Commons

"Killer Heat in the United States: Climate Choices and the Future of Dangerously Hot Days" calculated the average number of dangerously hot days throughout the country, historically and going forward, with the future outcomes dependent on the amount of action taken to combat climate change.

The average number of days per year nationwide with a heat index above 105 degrees Fahrenheit would more than quadruple to 24 by mid-century and increase eight-fold to 40 by late century, the analysis, published in the journal Environmental Research Communications, revealed.

By mid-century, defined by the report as 2036 - 2065, with no action taken to address climate change, Staten Island would experience 56 days per year with a heat index exceeding 90 degrees, 20 days with a heat index exceeding 100 degrees and nine days with a heat index over 105 degrees.

"The report clearly shows how actions taken, or not taken, within the next few years to reduce emissions will help determine how hot and humid our future becomes", scientists said. "Historically, such incalculable conditions have represented the world's most oppressively hot, dangerous, and, fortunately, rare days - those with a heat index well above 130°F". In one, carbon emissions continue to rise and the global average temperature increases about 8 degrees Fahrenheit above pre-industrial levels by the end of the century. And while high heat poses particular problems for children and the elderly - whose bodies can struggle to regulate temperature as effectively - it also can cause issues for people with both traditional medical and psychiatric conditions, according to the report.

Climate change will bring "potentially lethal heat" to every state in the contiguous U.S. in future decades, the report predicted.

In the USA, these "off-the-charts" days now occur only in the Sonoran Desert-located on the border of southern California and Arizona-where historically fewer than 2,000 residents have been exposed to the equivalent of a week or more of these conditions per year on average. By late century this would increase to areas where more than 118 million people-over one-third of the US population-live.

"We have little to no experience with "off-the-charts" heat in the USA", said Erika Spanger-Siegfried, lead climate analyst at the Union of Concerned Scientists and report co-author. The heat index is a combination of temperature and relative humidity that can result in conditions that feel hotter than what a thermometer records. "Exposure to conditions in that range makes it hard for human bodies to cool themselves and could be deadly".

The Southeast and Southern Great Plains regions of the country, UCS notes, "would bear the brunt of the extreme heat", but so-called "off-the-charts" days would be experienced by states and regions that rarely or ever see such days now, including much of the Midwest region.

By 2050, hundreds of American cities could experience an entire month each year with U.S. "heat index" temperatures above 100F (38C) if nothing is done to tackle emissions and the resultant climate crisis, scientists said.

MA now averages no days when the heat index tops 100 degrees, but without changes to global emissions that figure would rise to 10 days by mid-century and 26 days by century's end.

More than 6 million people would experience "off-the-charts" heat days for the equivalent of a week or more per year on average.

The report breaks down what each county in the nation can expect in terms of heat index measurements, or what it really feels like outside, before the end of the century.

With these estimates, Staten Island would experience nearly three months a year of 90 degree temperature, almost a month and a half of 100 degree temperatures and nearly an entire month of 105 degree temperatures.

Because this area is sparsely populated, only about 2,000 people are exposed to these extreme days for a week or more every year on average.