RENEE MONTAGNE, HOST:
Google is trying out one way of mapping climate change. It has outfitted a few of its Street View cars with special sensors to measure methane. WNYC's Robert Lewis road the streets of Manhattan to see how Google is mapping pollution across the country.
ROBERT LEWIS, BYLINE: The Subaru hatchback is painted like a Google map. A tower on top hold what looks like a futuristic soccer ball. That's the panoramic camera that takes those photos of buildings and streets you see on Google Maps in Street View mode. That's why when Justin Hagan drives through midtown Manhattan, a man in a suit jumps excitedly. Some schoolgirls snap iPhone photos, and a guy crossing the street smiles and makes an obscene gesture.
JUSTIN HAGAN: You get a lot of waves - a lot of really excited people think they're going to be famous and on the Google Street View.
LEWIS: It's another day in the life of a Google driver.
HAGAN: It's minor celebrity, but it's more the car than you.
LEWIS: But this car's not taking photos. It's one of three Street View cars outfitted with special equivalent to detect methane, the primary ingredient in natural gas. It's part of a partnership between Google and the Environment Defense Fund that's finding leaks in the thousands of miles of gas mains beneath streets in New York and other cities.
STEVEN HAMBURG: As we're moving, there's a pump that's sucking air from the hose that's right sort of in the bumper, and that's bringing it back to the rear of the car where there's the methane analyzer.
LEWIS: That's the fund's chief scientist Steven Hamburg as he rode along with Hagan on a recent morning. Hamburg is wedged in the back seat because there's a big monitor where the front passenger seat should be. A slow-moving line spikes up when the car's sensor detects methane.
HAMBURG: We have to use algorithms to understand are we passing a bus or that kind of thing because you can't do that in real time - figure out was that a natural gas bus that went by - or here, we've got a UPS fueling station. Let's see if it - I don't know if they have natural gas here or just petroleum. We didn't see any spike. It stayed at 1.9.
LEWIS: Those readings are pretty normal. But here's what the scientists found on New York's Staten Island.
HAMBURG: There was an average of one leak per mile. And that is similar to what we saw in Boston. But in Indianapolis where they've had a very active program of replacing the old pipes with new pipes - in fact, they have one leak perch 200 miles.
LEWIS: Leaks are pretty common in older cities like New York where a gas explosion in March killed eight people. But most of the leaks aren't necessarily dangerous. Instead, gas just escapes into the atmosphere. Utility companies haven't really paid a lot of attention to those. Hamburg says they should. Methane from natural gas doesn't stick around as long as carbon dioxide, but it carries 120 times the warming effect. And he says this project will show the spots causing the most pollution.
HAMBURG: We can reduce the emissions at a much faster rate than if they were to use their normal approach to figuring out where to repair the leaks and in what order.
LEWIS: So far, utility companies have been cooperating with the scientists, checking the results and sharing information. One utility spokeswoman says the data will be useful but that it's too early to say what will change. While the project is relatively small so far - just three cars - the researchers hope it's just the start and with Google's help, plan to look for more air pollution across the country. For NPR News, I'm Robert Lewis in New York. Transcript provided by NPR, Copyright NPR.