Scientists from the U.S. National Oceanographic and Atmospheric Administration for more than a dozen years have been studying something that we humans normally don’t sense: increasing underwater noise and its effect on marine mammals and other sea life.
One of NOAA’s findings is that underwater sound has been doubling every 10 years. Most of this sound is man-made, from the ever-expanding fleet of ships that ride our oceans. Researchers believe that intrusive sound is harming sea life. Whales in particular, are greatly affected by increasing undersea sounds, as they depend on hearing to find food and each other.
In response, the International Maritime Organization, part of the United Nations, has been deliberating on draft guidelines for the reduction of underwater noise from commercial ships.
Technologies for quiet ships have been in use for military vessels, especially submarines, since World War II. The submarine, after all, has been called “the original stealth fighter” in a defense contractor’s advertisement.
Designers of commercial ships began paying attention to noise about 20 years ago, with the design of quiet marine research vessels. The quieter the vessel, the less likely it is to disturb the populations of creatures that it is trying to study. This led the marine science community to push engineers, naval architects, and noise-control engineers to build quiet vessels for their work.
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