Katelyn Weisbrod | July 27, 2018

On Wednesday, the temperature in Phoenix broke a record high for the date — 116 degrees Fahrenheit.

The hot summer days are made worse in cities like Phoenix because of the “urban heat island effect.” When the sun beats down onto the cars, streets, and buildings covering the landscape, that heat is absorbed and held, leading to unnaturally high temperatures.

Cities can prevent the effect by increasing the urban plant life. Trees, gardens, and green roofs all help absorb less heat, and trees can provide much-needed shade to people walking around the sweltering city.

At least five people have died this year in the Phoenix area after falling sick from the heat, the Associated Press reported. Last year, the final death toll from heat-related illness was 155.

“If similar numbers of people died from any other type of weather event, it would be considered a national disaster,” Phoenix sustainability officer Mark Hartman told the AP.