The northern lights sometimes whisper at the approach of dawn, while North Pacific cyclones whine with a strange and subtle tone. This is not some poetic babble. A research team at the University of Alaska Fairbanks has been using sensitive arrays of microphones near campus and in Antarctica to eavesdrop on the cries and murmurs of earthquakes, marine weather, alpine winds, shimmering auroras and explosions of all kinds. By recording and analyzing sounds that ripple below the threshold of human hearing, scientists have found innovative ways to measure complex natural phenomena. At the same time, the research has opened an ear on a world most people scarcely imagine.A representative from the Geophysical Institute's Infrasound group presented reports in November on earthquake and auroral sounds during the annual American Geophysical Union meeting in San Francisco. They were among nearly 50 papers describing infrasounds produced by meteors, the space shuttle Columbia disaster and other jolts around the world.

"We're discovering things that people never saw before because of the tools we have now," said Fairbanks physicist John Olson, the group's principal scientific investigator. "These (sounds) are around us all the time. For instance, in Alaska, one of the biggest things we see day in, day out are the signals from marine storms. They're almost like a tone with a period of about five seconds."

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