You don’t need to be a climate scientist to know that the summer sun can turn the city into an asphalt sauna. WNYC's Fred Mogul reports on one researcher, who's studying how heat gathers on tree-less, open playgrounds – and what the city can do about it.

REPORTER: At the playground of PS 180, near Morningside Park, 1st grade summer school students run around playing soccer. They hardly care about where they’re kicking the ball, how hot it is, or what a scientist and three research interns are doing a few yards away. Stuart Gaffin and his team are measuring ground and air temperatures and the amount of sun light different surfaces reflect.

GAFFIN: The surface is 134.0, and the air above it is 91.

REPORTER: Gaffin teaches urban climatology at Columbia University and is affiliated with Nasa’s Goddard Institute for Space Studies. He and his team are doing an informal study comparing two very different kinds of playgrounds at two Harlem schools -- one old and one new. Here at PS-180.

GAFFIN: There’s a black asphalt surface they’ve painted. There’s a red running track. There’s a blue tennis-court-like thing. And there’s the astro-turf.

REPORTER: The other one, a few blocks away at PS 144, is the classic concrete special: a quarter-acre of plain asphalt, enclosed by the building on two sides and a tall chain-link fence on the other two. Gaffin walks back and forth, holding an umbrella to shade both him and the pistol shaped digital thermometer. He’s taking readings of air and ground temperatures every five paces.

GAFFIN: 119.4 ground, 88.9 air…We find you have to do a lot of sampling to see the patterns…116.1, 88.3…especially for the air temperature…

REPORTER: Certain things are obvious: both of these places could use a lot more shade, black surfaces get a whole lot hotter than those painted white, blue or red; and a nice green-grass lawn would be wonderful, if it weren’t pretty much impossible to maintain in a schoolyard. Certain things are less obvious. For instance: Well-intentioned ‘astro-turf’ appears to get even hotter than asphalt.

GAFFIN: : There’s no water evaporating from this. It’s essentially a dry surface that’s dark, and it’s a very effective light trapper. And also, it heats up rapidly, so we think this is one of the hottest surfaces you can create.

REPORTER: Gaffin cautions that the data have not been fully compiled and analyzed. But back in the office, he says he hopes the resulting comparison study will help cities design smarter, more inviting parks and playgrounds.

GAFFIN: The hope is we’ll be able to pick up subtle things. That would really be the goal. Where we can actually see the differences between types of trees, and the ways they’ve been planted ...The children should be informed, and…maybe they’ll have some ideas about what they might like as ways to improve it.

REPORTER: In the meantime, the kids at PS 180 don’t seem to mind as much as the adults that the sun’s beating down on them, interrupted only by the very occasional cloud. No that they’re totally oblivious to it. Just ask 7-year-old Erin Cunningham.

CUNNINGHAM: I’d rather play in the shade, because if you play in the shade, because if you play in the sun, you might get real sweaty, and you don’t feel comfortable.

LINKS:
The Center for Climate Systems Research