In World's Hottest Places, Heat Waves Push Limits of Human Survivability

Jul 20, 2023

Summer heat waves in some parts of the world are becoming intense. So much so that they’re pushing the limits of human survivability.

Recently, soaring temperatures in some very hot places have approached or beat records. On Tuesday, Phoenix had its 19th straight day of 110-degree Fahrenheit daytime temperatures or higher. This passed a record set in 1974. The day before, northwest China suffered an all-time high of 126 degrees. 

California’s Death Valley was extremely hot on Sunday. The famous sign in at the visitors center read 133 degrees. That's one degree less than Earth’s hottest-ever recorded temperature. That was reached in 1913. Across the world, the heat index hit 152 degrees in Iran. The index is a measurement of the temperature and humidity together.

A 160-degree heat index is widely considered the limit for human beings for a few hours outdoors. Climate change is helping push these limits, scientists say. 

“We know these extreme temperatures are killing people right now,” Cascade Tuholske told The Washington Post. He is a Montana State University climate science assistant professor. 

How many people have died in 2023 isn't known yet. However, a study published last week in the journal Nature Medicine found that almost 62,000 people in 35 European countries died from heat-related causes in summer 2022. That was Europe's hottest summer ever recorded.   

At extreme temperatures, the human body stops being able to cool itself. Air conditioning, shade, or fans are needed to help. But those are not always available. This can result in heatstroke. It can make the heart beat too fast, damage the brain, and shut down the body. 

Ben Zaitchik is a climate science professor. He told The Associated Press, “Heat is the silent killer. No one thinks about it." 

Photo from Reuters. 

Reflect: What do you think it means to “think globally, act locally,” and how does it relate to climate change?

What is the connection the article makes between the US, China, and Iran? (Common Core RI.5.3; RI.6.3)
a. They all have similar climates in the summer.
b. They all have experienced record-breaking temperatures this summer.
c. They have all started measures to fight the effects of the heat waves.
d. Fewer people are dying from heat waves in these countries.
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