Q&AZ: What if climate change makes Phoenix uninhabitable?

Phoenix has been one of the fastest-growing cities in the United States for several years now.

But via KJZZ’s Q&AZ reporting project, one listener asked: What happens if climate change makes Phoenix uninhabitable?

As it turns out, parts of Arizona have been deemed uninhabitable before - the ancestral Pueblo abandoned the Southwestern desert about 800 years ago due to an extended drought known as the Great Drought, which made it difficult to survive in the desert.

In 2025, Phoenix is also facing an extended drought - ours is just over 30 years old.

The city is also facing increasing temperatures in the metro area, breaking records year after year.

Glynn Hulley with NASA’s Jet Propulsion Lab said a lot of scientists have been interested in the fact that Phoenix’s nighttime temperatures have been consistently breaking records during the summer.

”That’s particularly concerning,” he said, “because we also see a strong correlation between human health and heat for nighttime temperatures, not necessarily daytime temperatures.”

Hulley said the livability of a place is determined by the “wet bulb globe temperature,” which takes into account various weather factors like temperature, humidity, wind speed and others.

He said 90 degrees on that index is the point where it becomes dangerous for humans to work outside, and that a team of scientists used existing data to make a prediction for what would happen to Phoenix if climate change continues unabated.

”They counted the number of days in the year that would reach that threshold by the end of the century, and it was almost half the year,” he said.

Phoenix also isn’t the only city facing this potentially dark future - Jakarta was the capital of Indonesia before it was destroyed by flooding from rising sea levels, groundwater pumping and subsidence.

The capital has since been moved to a city called Nusantara.

Even closer to home, the Los Angeles area is facing historic wildfires that so far have burned an area larger than San Francisco with more than 150,000 people under evacuation orders - and climate change is a key culprit.

It’s not all doom and gloom for Phoenix, though.

Hulley said that initiatives like the city’s Cool Pavement Program and its efforts to create more green and shaded spaces in the city will help keep Phoenix’s temperatures lower and reduce the effects of climate change - so long as they continue to be implemented and maintained.

Green spaces in particular are one of the best ways to mitigate the effects of climate change, according to Hulley.

”It’s really trees and tree canopies that provide the optimal cooling,” he said, “because you get the combined effect of the tree itself cooling the air around it through transpiration and also providing shading.”

According to the USDA, shade provided by plants can be nearly 20 degrees cooler because plants release water vapor, the same reason some restaurants and stores in the Valley use misters outside during the summer.

The question of how climate change will affect Phoenix has an easy answer - but only time will tell how the people of Phoenix will choose to react.