Consider, for a moment, how many sounds you hear in a single day. Now try to imagine how many sounds are generated on the planet over a 24-hour period. What would that, er, sound like?
This is the Earth Day project of Bryan Pijanowski. From Wired:
“I’ve been on a campaign to record as many ecosystems as possible,” said Pijanowski, a soundscape ecologist at Purdue University. “But there’s only so many places in the world I can be. I thought about how I could get more recordings into a database, and it occurred to me: We have a couple billion people on this planet with smartphones!”