There are a couple of ways to forecast the destructive potential of a hurricane （飓风） so that people in the way can take adequate precautions （预防措施）．Satellite images of cloud patterns can be analyzed to estimate peak wind speeds，but the estimates are often way off the mark．Specialized aircraft can fly into a storm to measure the winds directly，but the flights are costly．
Researchers at the Massachusetts Institute of Technology come up with a third way：listening to a storm underwater．
In a paper to be published in Geophysical Research Letters，Nicholas C．Makris and a former graduate student，Joshua D．Wilson，report a strong connection between the intensity （强度） of sound recorded by an undersea microphone in the mid-Atlantic and the wind power of a hurricane that passed over it．They say that such microphones，known as hydrophones，could be a safe and relatively inexpensive means of estimating hurricane force．
Dr．Makris and Dr．Wilson，who are now with Applied Physical Sciences Corporation，worked out the theory of underwater acoustic （声音的） monitoring of storms in a 2005paper．"To be very frank with you，it's a mystery what makes storms noisy underwater．"Dr．Makris said．The most popular idea currently is that it has something to do with oscillating air bubbles （气泡振动）．
The researchers then went looking for experimental data to back their theory，and found it from a hydrophone placed at a depth of 2，500feet by the National Atmospheric and Oceanic Administration．It happened that Hurricane Gert passed over the area in September 1999，and a hurricane-hunter plane directly measured the wind speed at the same time．The hydrophone data showed sound intensity rising when the storm's outside wind"wall"passed over，and again when the inside wall，the most destructive part of the storm near the eye，passed over．"We got a beautiful connection，"Dr．Makris said，"between the hydrophone data and the actual wind speeds as measured