A killer combination of high heat and high humidity is gripping much of the midwestern and northeastern U.S., Canada, and the U.K., and producing disturbing headlines. Among them: some 70 deaths are attributed to the recent Canadian heat wave, and roads in Pennsylvania are said to be melting; meanwhile, new research suggests prolonged heat exposure can create measurable declines in cognitive ability.
The frequency of lethally hot weather is increasing, as is the duration of high-risk heat. These facts are grim reminders of the findings of a report, published late last year, by climatologists from Columbia’s Lamont-Doherty Earth Observatory. The researchers reported that, considering the present climate change trajectory, heat stress could exceed human endurance by the end of the century.
“Climate change has already loaded the dice in favor of more frequent extreme heat events, ” said Lamont-Doherty climatologist and study author Radley Horton. “Since 2000, the U.S. has experienced approximately twice as many record-breaking high temperatures as record breaking low temperatures.”
The report discusses “wetbulb” measurements, an index of the combination of heat and humidity. The news is not good, especially for those in southeastern U.S., South America, Africa, India and China.
“The conditions we’re talking about basically never occur now—people in most places have never experienced them,” said lead author Ethan Coffel, a graduate student at Lamont-Doherty. “But they’re projected to occur close to the end of the century.”
Although the report’s most grim projections are set in the future, the increasing periods of high heat and humidity are already having dramatic health impacts.
“The health dangers associated with extreme heat and humidity remain grossly underappreciated,” said Horton. “As temperature and humidity rise in the future, more and more regions will experience conditions in which outdoor labor is dangerous, and air conditioning is essential.”
Read the full news report from December 2017.
While the news isn’t pleasant, these findings—not to mention this summer’s record-breaking temperatures and oppressive mugginess—are great reminders that we need to cut our carbon emissions. Here are a few things you can do to make a difference.