Heat waves across the world and potentially record-breaking high temperatures in the western United States are bringing renewed attention to the dangers of heat stress.
Purdue researcher Matthew Huber is one of the world's leading experts on heat stress. He co-authored a 2010 paper that looked at how much heat the human body can withstand - and whether climate change could make parts of the world uninhabitable.
“I would say this is the single biggest impact of climate change,” Huber said. “Bigger than sea level rise, bigger than melting ice caps, it’s bigger than any other thing.”
Huber’s work has found that prolonged periods with high humidity and temperatures above 35 degrees Celsius would keep people from being able to cool off - meaning staying outside could be lethal.
“We’re assuming when we do these calculations that people are perfectly fit,” he said. “Real humans are rarely fit, rarely acclimated. All those factors render humans more vulnerable.”
With each degree of global warming, Huber said more parts of the world will be potentially uninhabitable without air conditioning for long stretches.
“It’s not like all of a sudden the world ends if you go from 2C to 3C [of warming],” he said. “But when you look at how much of the world is covered by high-heat stress kinds of conditions the blob just keeps getting bigger and bigger and encompassing more and more regions with each degree of warming. Any amount of avoided warming is a good thing.”
Huber said as the world continues to warm access to things like air conditioning will become essential.
“Heat stress is going to be, in my opinion, one of the big things if not the biggest thing we need to be prepared for,” he said. “We’re going to find ourselves declaring that it should be a human right to have air conditioning.”
Heat related deaths in the western U.S. last week were primarily among farm and warehouse workers.