A new study found that, if greenhouse gas emissions continue at their current rate, global warming could bring potentially lethal temperatures.
Earth's current warming trend could bring deadly heat for humans.
A new study that looked at reasonable worst-case scenarios for global warming found that if greenhouse gases continue to be emitted at their current rate, temperatures could become deadly in coming centuries.
Researchers calculated the highest tolerable "wet-bulb" temperature — equivalent to what is felt when wet skin is exposed to moving air — and found that this temperature could be exceeded for the first time in human history if greenhouse gas emissions continue at their current rate and future climate models are correct. Temperatures this unbearable for humans haven’t been seen during the existence of hominids — the primate family that includes ancient humans — but they did occur about 50 million years ago.
Exposure to wet-bulb temperatures above 95 degrees for six hours or more will create lethal stress levels in humans and other mammals, said study team member Matthew Huber of Purdue University’s earth and atmospheric sciences.
Huber said that while areas of the world regularly see temperatures above 100 degrees, really high wet-bulb temperatures are rare because the hottest areas of the planet normally have low humidity — think Arizona’s dry heat. Areas of the world such as Saudi Arabia have the highest wet-bulb temperatures near the coast where winds occasionally bring extremely hot, humid ocean air over hot land leading to unbearably stifling conditions.