A new study shows a wide range of possible thermal impact scenarios by 2100. The results are published in the journal Communications Earth & Environment.
The top panel shows the historical record of “dangerous” days in a year when the heat index exceeded 39.4 °C. The left column shows the temperature range for the year 2050. The right column shows the temperature range for the year 2100. Authors and rights: Vargas Zeppetello et al./Communications Earth & Environment
In the study, scientists looked at a combination of temperature and humidity – the heat index. It helps measure the effects of environmental heat on the human body. According to the U.S. National Weather Service, the heat index is “dangerous” at 39.4 °C and “extremely dangerous” at 51 °C.
Originally, these standards were created for people who work in places like boilers. “No one would have guessed that they would show up outdoors, in the environment. But we’re seeing them now,” Vargas Zeppetello points out.
The study found that even if countries succeed in meeting the Paris Agreement goal, by 2100 dangerous levels of heat will be three to 10 times more common in the United States, Western Europe, China and Japan than they are now. And in the tropics, the number of record hot days will double and will be observed within half a year.
Recall that the goal of the Paris Agreement is to reduce global greenhouse gas emissions and limit the global temperature increase this century to 2 °C.
