Even in parts of the United States that are notoriously hot, like California’s Death Valley, it’s getting hotter. On Sunday, Death Valley reached the hottest global temperature since records officially began in 1931. The area reportedly clocked in at 130 degrees Fahrenheit.
The notion that a place known for extreme heat can still become even more shockingly hot is explored in new research, which examined the locally specific factors that make extreme heat uncomfortable and potentially dangerous. Focusing on local factors, including population, helped researchers determine which major US cities are set the face the most dramatic heat exposure in the coming decades.
Major metropolitan areas including New York, Los Angeles, and Washington, DC will see the greatest absolute increase in people affected by extreme heat, research published Monday in the Proceedings of the National Academy of Sciences finds.
The most intense relative increase — calculated by combining temperature factors with population growth — will be in places like Orlando, Miami, and Austin. Because those cities are growing rapidly, more residents will inevitably be exposed to extreme heat, creating a bigger change relative to the beginning of this century. Atlanta, Georgia, made both lists.
Researchers predicted for extreme heat and cold exposure in 47 major cities in the US, accounting for population size, warming caused by urban development, and local standards for extreme heat. Overall, the study showed that people in those cities will experience up to 30 times more extreme heat by the end of the century, compared to previous projections.
The study team argues that cities must prepare at the local level to avoid the most dangerous human outcomes: serious illness and death resulting from extreme heat.
Matei Georgescu is an associate professor at Arizona State University and led the study. He tells Inverse that while temperature increase is happening everywhere, the feeling of it being incredibly hot changes based on the area’s standards and expectations.
“We develop locally specific definitions of what constitutes extreme,” Georgescu says.
A 100-degree day in a semi-arid location Pheonix, for instance, would feel pretty comfortable to locals. The same heat in New York City could result in fatalities — especially among, more vulnerable populations like people who are elderly and homeless.