I know some guys who will, on occasion, perform questionable experiments in an effort to gain some piece of knowledge no one really cares about. They call it doing Science, with a capital S. Â What the University of Southern California’s Viterbi School of Engineering is doing reminds me of those silly experiments; the only difference of course is that USC is legit.
Trying to answer the question, “Just how polluted is the sky?”, the team at USC has created an app for Android to measure the sky for pollutants using the smartphone’s camera and internal sensors.
In a paper on the app, Sukhatme points out that in the western skies, the natural visual range should be close to 140 miles on a clear day. But over the decades, man-made pollution has reduced that to between 35 and 90 miles. And then there are the numerous, oft-cited health risks of airborne particulates, including lung and heart problems.
The USC team has devised an algorithm that uses the phone’s location and the direction it was pointing to determine how bright the sun should be in your image. It then looks at your photo to see how much that theoretical sunlight has been obscured, and from that calculates how much gunk is in the air (it doesn’t work yet on highly cloudy days).
This is where the crowd-sourcing comes in. Their app, Visibility, is available on the Android Market. Anyone can download the app, take a photo of the sky, and send it to the USC lab for analysis. The more photos there are of course, means the more data there is to compare on levels of pollution.
So the next time someone asks you why you’re taking a picture of an otherwise smoggy day, you can say you’re doing Science. You can download Visibility HERE, or scan the QR code below.
Source: LA Times
