Transcript for the Piece Audio version of Tales...Story 5:The Urban Heat Island: Problems and Solutions

Narration: In summer evenings the air temperature in cities can get several degrees hotter than in the surrounding country side. Scientists call this affect on urban areas an "urban heat island." Atlanta has one, and its growing. Keeping pace with the city’s urban and residential development. To give hope in the heat, people and organizations are working on ways of cooling their neighborhoods. Lucy Griggs is with ‘Cool Communities’, a group that promotes ways of dampening the effects of an Urban Heat Island, including simple ways, like shade trees.

LUCY GRIGGS: Everything you needed to know about Urban Heat Islands you learned in kindergarten, you just didn’t know it. Say you’re barefoot and walking toward the pool, so you run across the parking lot until you’re under the shade tree and then to the cooler pool deck.

Narration: Outside Atlanta’s baseball stadium on a mild summer day, Cheryl Kortemeier (COURT – meyer), uses an infrared heat gun to measure the temperature of the parking lot.

CHERYL KORTEMEIER: Uh, lets just say you would not want to walk barefooted on this parking lot right now. It’s probably a comfortable temperature maybe for a hot tub (laughs).

Narration: Kortemeier works for the group that helped plant these Red Oak trees in a parking lot at Turner Field.

CHERYL KORTEMEIER: The temperature again here in the shade is 110 and here in the sun right next to it is 131 degrees so we’re showing a 21 degree difference here.

Narration: For years NASA has been studying Atlanta and measuring the effects of the city’s urban heat island. The scientist in charge of the project is Dale Quattrochi (Qua-TRO-key), a Senior Research Scientist with NASA at the Marshall Space flight center in Huntsville, Alabama.

DALE QUATTROCHI: UHI is really a formation caused by a dome of elevated air over a city because we replaced trees and vegetation with concrete and asphalt and with clear skies and intense solar radiation, these surfaces store and release long wave energy (energy we can feel) and can raise air temperature 2 to 10 degrees more than the surrounding country side.

Narration: While trees are one way to cool a city, using a different kind of pavement is another. Used on low impact surfaces like driveways and parking lots, ‘pervious concrete’ is a newer type of paving option.

GORDON KENNA: Pervious concrete is a concrete mix made without sand or fine materials, it’s designed to allow water to percolate through the material.

Narration: Gordon Kenna is the Executive Director of the Georgia Concrete and Products Association.

SFX: water running from a faucet.

GORDON KENNA: So there’s the water pouring on t he surface of the pervious pavement and it just comes right out the bottom.

Narration: Here Kenna holds a sample of pervious concrete under a stream of water. It’s a small round disk, and looks more like a thick rice crispy treat.

GORDON KENNA: This material actually drains faster than just about anything in nature because of the very high void content. And so you can’t overwhelm this in terms of rain, in other words, this is always going to drain faster than it rains.

Narration: One of pervious concrete’s main advantages is linked to that ability to drain quickly. It reduces storm water run off and reduces flooding. And that water that is taken to nearby streams is much cleaner and cooler. The reason for Atlanta’s Urban Heat Island is because of the development that’s happened in the city over the last 20-years, but that doesn’t mean smaller cities are cool. In fact, nearly every city has an Urban Heat Island. And the larger the city, the larger the heat island. Once again Dale Quattrochi (Qua-TRO-key).

DALE QUATTROCHI: We have Atlanta with a very large UHI, LA or Huston, or even smaller cities, there is still going to be an UHI effect, regardless of how small the city it. .
And so ultimately what we’re seeing is that despite the fact that you may live in a relatively small town you must still be cognizant of the fact that you can in fact impact your own back yard.

Narration: And so in Atlanta can be made by putting down pervious surfaces and planting trees. For Soundprint David Barasoain (BEAR-es-wayne).