The heat is on, and taking a toll. In Arizona this week, it was literally too hot fly. Temperatures in Phoenix reached 119 degrees Fahrenheit, grounding the regional flights of American Eagle, which flies smaller Bombardier CRJ planes. (We’ll know it’s really hot when larger Airbus and Boeing flights are disrupted. Their temperature limit are 127 and 126 degrees, respectively.)
Such heatwaves could become more common. A new study in Nature, “Global Risk of Deadly Heat,” projects that if carbon emissions continue to rise, by 2100, up to 74% of all humans could experience deadly heat waves. Already roughly 30 percent of us live in places with potentially deadly heatwaves at least 20 days a year. Researchers identified 783 deaths linked to heat between 1980 and 2014 in 164 cities in 36 countries.
Even with drastic reductions in emissions, the researchers predict, up to half the population will still likely be exposed to regular deadly heat. And even if the heat doesn’t kill us, it’s likely to take its toll on the economy and elsewhere. Popular Science reports worker absenteeism during a 2013/2014 heatwave in Australia cost the country’s economy $6.2 billion. Another study, published in 2009, found that excessive heat in India and Vietnam caused construction and factory workers to take extended breaks, pushing 8- to 10-hour days to up to 16 hours. “An increasing threat to human life from excess heat now seems almost inevitable,” conclude the authors of the study in Nature, “but will be greatly aggravated if greenhouse gases are not considerably reduced.”