The oceans are getting louder, and it's not the waves

With population increases and booming construction occurring worldwide, excessive din on land should be expected - but a new study done by U.S. researchers shows that life underwater is not that much different.

Researchers from Scripps Institution of Oceanography at the University of California conducted a study showing that underwater marine life may be suffering from an excess of noise - increasing over time.

The researchers compared acoustic data recorded between 1964 and 1966 to data collected between 2003 and 2004.

The results showed that the noise levels in the more recent years were ten to 12 decibels higher than the older data.

The scientists say that this increase is mainly due to an increase in global shipping trade, with ships using higher speeds and more propulsion power.

The number of commercial fleets has doubled in the past 38 years, from about 40,000 to close to 90,000 fleets, according to the study.

In order to fully understand the type of impact this puts on sound-dependent marine life, the researchers say further acoustic measurements will have to be done.

The researchers' study was published in the August issue of the Journal of the Acoustical Society of America.

Photography: NOAA

Source: Discovery Channel Reports, August 22 edition