Downtown Phoenix is using urban forestry and studying ways they can lessen the urban heat island during a time when climate change is considered a national crisis.
Doctor Erinanne Saffell, a climatologist at Arizona State University, explains that Urban environments use materials like metal, glass windows and asphalt within a city’s infrastructure. All of which capture heat from the sun and slowly release that heat into the atmosphere during the night.
This release of heat during the night is considerably higher, causing temperatures to be higher than there would be without human activity. Residents stay comfortable at night by turning up the A/C, which in turn releases more energy back into the atmosphere causing temperatures to increase.
“Phoenix was number two in greatest increase in population last year,” Saffell said. She also said she believes the more people that settle in the Phoenix area will cause the urban heat island to worsen due to the energy needed to cool a higher population.
Residents have felt this population growth during the last year as Phoenix broke the record for most recorded days over 100 degrees Fahrenheit in 2020, reaching over 143 days above 100 degrees.
But there are ways residents can fight the effects of climate change and help control urban heat islands, according to Saffell.
“People can plant grass and trees in their yard. This will help heat not be absorbed from the ground,” Saffell said.
Saffell said her neighborhood used a flood irrigation system that released water into her yard to water her grass and plants. The evaporation from the irrigation system helped cool the neighborhood.
“I was about 10 degrees cooler than other neighborhoods close by because I had a flood irrigation system,” she said.
Jamie Teran, a graduating Geography (Meteorology-Climatology) student, said he predicts if the nation doesn’t begin to make changes the number of days above 100 degrees Fahrenheit will continue to increase in Phoenix.
Teran’s prediction falls in line with the latest trends. Statesatrisk.org ranks Phoenix the second fastest warming city in the United States with an increase in average summer temperatures of 1.8 degrees warmer since 1970.
Saffell said she believes that if we don’t take precaution with the urban heat island and energy consumption Phoenix will become drier and our water systems will also change. Areas will end up with too much water and others will end up with not enough.
“Arizona already averages more than 50 dangerous heat days a year, the second highest in the nation. By 2050, Arizona is projected to see almost 80 such days a year,” said Statesatrisk.org.
Contact the reporter at lvickery@asu.edu.
