Office Hours: What is the urban heat island effect?
Arne Winguth, professor of earth and environmental sciences, joined Office Hours to explain why the Dallas-Fort Worth area is highly susceptible to the urban heat island effect.
What is the urban heat island effect?
“The urban heat island effect,” Dr. Winguth said, “is defined by the temperature difference between the downtown area and the rural area.”
Why is North Texas especially susceptible to the urban heat island effect?
Winguth: In the summertime, you have a high-pressure system with subsidence of air from above to the ground, which creates a heat dome over metropolitan areas like the Dallas-Fort Worth area.
What happens to the heat absorbed by concrete and asphalt?
Winguth: Concrete and asphalt surfaces have lower soil moisture and you do not have the cooling effect of evaporation. In rural areas, you do have vegetation and trees, which create a cooling, evaporative effect.
If I’m in downtown Dallas on a summer evening, how much hotter is it than the surrounding countryside?
Winguth: We assessed data from 2001 to 2011, and over that period the temperatures at 9 p.m. were about two degrees warmer in downtown areas compared to the rural areas.
Does the urban heat island move or are the same areas consistently the hottest?
Winguth: We noticed that the urban heat island increased in areas where you changed the surface area, building large warehouses or large construction areas. Changing these surfaces leads to an acceleration of the urban heat island.
What advice would you give to cities to help reduce the urban heat island effect?
Winguth: There are several ideas for how to mitigate the urban heat island effect. Surfaces which can absorb the soil moisture, increasing the amount of trees. There are efforts to have more green buildings or even vegetation on roofs, which can substantially reduce the urban heat island effect. There have been many successful studies in, for example, New York, the West Coast, Portland, and in Europe, showing that greening cities leads to mitigation of the urban heat island effect.
About The University of Texas at Arlington (UTA)
The University of Texas at Arlington is a growing public research university in the heart of Dallas-Fort Worth. With a student body of over 42,700, UTA is the second-largest institution in the University of Texas System, offering more than 180 undergraduate and graduate degree programs. Recognized as a Carnegie R-1 university, UTA stands among the nation’s top 5% of institutions for research activity. UTA and its 300,000 alumni generate an annual economic impact of $28.8 billion for the state. The University has received the Innovation and Economic Prosperity designation from the Association of Public and Land Grant Universities and has earned recognition for its focus on student access and success, considered key drivers to economic growth and social progress for North Texas and beyond.