Science Diary: Volcano – Analyze
Ambience: crowded room, volcanic eruption
Have you ever noticed that in a crowded room, we have the ability to focus our attention and tune in on just one conversation? Well, scientists are using their listening skills to tune in to some of nature’s loudest and deepest sounds. Welcome to Pulse of the Planet’s Science Diaries, a glimpse of the world of science from the inside. Milton Garces is the director of the University of Hawaii’s Infrasound Laboratory. He uses groups, or arrays of microphones to hone in on the low frequency sounds produced deep inside volcanoes.
Garces: The human acoustic sensing system consists of our two ears, which are like two microphones. And this is what allows us to tell direction. Now, if we had more ears than two, then we’d have even better spatial spatial resolution of where sound is coming from. So this is one reason why we use arrays.
But determining where a sound is coming from is just one challenge. Another is finding a way to cut through all the other noise that competes with the volcano’s sounds. We’re listening to recordings made at Stromboli volcano in Italy.
Garces: If you have a windy environment, it’s really difficult to be able to recognize a signal from the noise. With a crowded room, you tune into the pitch, to the intonation of the person you’re communicating with. This is one of the things that we try to do with our volcanoes. Once we identify what those are, things become a lot easier. Now we can start only selecting those signals that correspond to our volcano.
Isolating and analyzing a volcano’s signals can give us a better understanding of volcanic activity. Please check out our new project, the Kids’ Science Challenge, at pulseplanet.com. Pulse of the Planet’s Science Diaries are made possible by the National Science Foundation.