Noise Pollution Has Reached The Oceans

Pollution really has engulfed our lonely planet from all angles. Even the underwater world is given no escape, as new research published in the August issue of the Journal of the Acoustical Society of America (JASA) has shown a tenfold increase in underwater ocean noise off Southern California’s coast. This is huge, as compared with the 1960’s records. Mark McDonald of WhaleAcoustics in Bellvue, Colo., and John Hildebrand and Sean Wiggins of Scripps Oceanography accessed acoustic data recorded in 1964-1966 through declassified U.S. Navy documents and compared them against acoustic recordings made in 2003-2004 in the same area off San Nicolas Island, one of the Channel Islands more than 160 miles west of San Diego.

According to the study, 2003-2004 showed results that noise levels at that time were 10-12 decibels higher than in 1964-1966, or an average noise increase rate of three decibels per decade. “WeÂ’ve demonstrated that the ocean is a lot noisier now than it was 40 years ago. The noise is more powerful by a factor of 10,” said Hildebrand. This data can most probably be attributed to the vast increase in the global shipping trade, the number of ships plying the world’s oceans and the higher speeds and propulsion power for individual ships. “If weÂ’ve doubled the number of ships and weÂ’ve documented 10 times more noise, then the noise increase is due to both more ships and noisier individual ships than in the Â’60s. And that may be because the ships are now bigger, faster and have more propulsion power. The next step is to understand what aspect of modern shipping has resulted in more noise per ship,” Hildebrand further explains.

While there are no known impacts yet of such increase in the ocean’s noise level to marine animals, the authors have argued that repeated acoustic measurements at multiple sites are needed to understand what impacts such noise might have on sound-dependent marine animals and other sea life.

“The impact of the increased noise on marine animals is unknown,” said Hildebrand. “If impacts are shown to exist, what can be done to protect marine animals? For instance, it may be appropriate to move shipping lanes away from areas where there are concentrations of marine animals. The impact of ocean noise pollution may be minimized by diminishing the noise source or by separating the noise from things that are sensitive to it.”

Via Physorg

Pollution really has engulfed our lonely planet from all angles. Even the underwater world is given no escape, as new research published in the August issue of the Journal of the Acoustical Society of America (JASA) has shown a tenfold increase in underwater ocean noise off Southern California’s coast. This is huge, as compared with the 1960’s records. Mark McDonald of WhaleAcoustics in Bellvue, Colo., and John Hildebrand and Sean Wiggins of Scripps Oceanography accessed acoustic data recorded in 1964-1966 through declassified U.S. Navy documents and compared them against acoustic recordings made in 2003-2004 in the same area off San Nicolas Island, one of the Channel Islands more than 160 miles west of San Diego.

According to the study, 2003-2004 showed results that noise levels at that time were 10-12 decibels higher than in 1964-1966, or an average noise increase rate of three decibels per decade. “WeÂ’ve demonstrated that the ocean is a lot noisier now than it was 40 years ago. The noise is more powerful by a factor of 10,” said Hildebrand. This data can most probably be attributed to the vast increase in the global shipping trade, the number of ships plying the world’s oceans and the higher speeds and propulsion power for individual ships. “If weÂ’ve doubled the number of ships and weÂ’ve documented 10 times more noise, then the noise increase is due to both more ships and noisier individual ships than in the Â’60s. And that may be because the ships are now bigger, faster and have more propulsion power. The next step is to understand what aspect of modern shipping has resulted in more noise per ship,” Hildebrand further explains.

While there are no known impacts yet of such increase in the ocean’s noise level to marine animals, the authors have argued that repeated acoustic measurements at multiple sites are needed to understand what impacts such noise might have on sound-dependent marine animals and other sea life.

“The impact of the increased noise on marine animals is unknown,” said Hildebrand. “If impacts are shown to exist, what can be done to protect marine animals? For instance, it may be appropriate to move shipping lanes away from areas where there are concentrations of marine animals. The impact of ocean noise pollution may be minimized by diminishing the noise source or by separating the noise from things that are sensitive to it.”

Via Physorg