Every year city temperatures are rising due to climate change. It is getting to such temperatures that urban planners are looking of ways to alleviate the heat. The task was taken up by University of Utah.
They conducted the study by measuring the temperature and humidity in five parks and their adjoining neighbourhoods. They found that the neighbourhoods filled with impenetrable surfaces were drier and warmer than the equivalent parks. Sometimes up to 2 degrees warmer, even at night! A surprise the study did through up was; lawns were more effective at lowering the temperature than trees, again, even at night. They found that the trees did provide shade from the sun, but they found what was more effective at reducing heat was the water from the lawn would evaporate which in turn would cool the surrounding air.
Carolina Gomez-Navarro, postdoctoral researcher at the University said
“It’s intuitive — we’ve all stood in a parking lot on a hot summer day, and you feel the heat from the ground. And when you’re standing on a lawn, it’s cooler,”
The study goes on to say that a lot of the heat built up during the day dissipates throughout the night. But when you have a lot of dense tree cover, the trees trap the warm air and stops it from escaping. The study came to the conclusion that most effective way for urban cooling was to use a mixture of lawn and trees that were spread out over an area so that they didn’t act as a heat trap.