Study: Environmental Gap Widens In Phoenix
December 28, 2011

Residents of affluent neighborhoods like Equestrian Estates in Phoenix, shown above, typically have more access to foilage and vegetation -- and the cooling effects they provide -- than residents of lower-income communities. Photo courtesy of Chris Martin.

PHOENIX -- Phoenix is an ideal place to study climate change in an urban environment, scientists say. That's because it's hot here in a way that they predict other American cities soon will be.

University researchers recently released a study that says we're not all going to be hit with the effects of urban heating equally.

Ecologists Darrel Jenerette and Chris Martin crunched 30 years worth of census data and satellite imagery, as part of a grant from the National Science Foundation. They found that wealthier people in Phoenix don't just have more money: They also have more trees. This is new. In 1970, there was no relationship between tree-accessibility and income.

"Obviously, I was shocked," Martin said, of the finding.

Martin noted this about more than just aesthetics. Vegetation - and the cooling effects it provides - helps mitigate heat-related costs, like air conditioning bills, and heat-related illnesses, like heat stroke.

"People in these higher economic neighborhoods have to begin to realize that it’s to their advantage to see that these lower socioeconomic neighborhoods are vegetated," Martin said. "Because collectively, as a society, we’re paying for these issues. The health-related problems that are caused by this are borne by the entire population."

The City of Phoenix seems to agree. Its set an ambitious goal of covering at least 25 percent of the city in a canopy of trees by 2030, ideally with heat-tolerant, low water-use vegetation. Currently, only 12 percent of Phoenix is shaded.