Ocean noise pollution

Some scientists say that animals in the ocean are increasingly threatened by noise pollution caused by human beings.

The noise that affects sea creatures comes from a number of human activities. It is caused mainly by industrial underwater explosions, ocean drilling, and ship engines. Such noises are added to natural sounds. These sounds include the breaking of ice fields, underwater earthquakes, and sounds made by animals themselves.

Decibels measured in water are different from those measured on land. A noise of one hundred-twenty decibels on land causes pain to human ears. In water, a decibel level of one-hundred ninety-five would have the same effect.

Some scientists have proposed setting a noise limit of one-hundred-twenty decibels in oceans. They have observed that noises at that level can frighten and confuse whales.

A team of American and Canadian scientists discovered that louder noises can seriously injure some animals, the research team found that powerful underwater explosions were causing whales in the area to lose their hearing. This seriously affected the whales’ ability to exchange information and find their way. Some of the whales even died, the explosions had caused their ears to bleed and become infected.

Many researchers whose work depends on ocean sounds object to a limit of one-hundred-twenty decibels. They say such a limit would mean an end to important industrial and scientific research.

Scientists do not know how much and what kinds of noises are harmful to ocean animals. However, many scientists suspect that noise is a greater danger than they believed, they want to prevent noises from harming creatures in the ocean.

海洋噪音污染
一些科学家认为，海洋动物正日益受到人类造成的噪音污染的威胁。
影响海洋生物的噪音来自一些人类活动。它主要由工业水下爆炸，大洋钻探，及船舶发动机造成的。这种噪音是在自然界声音的基础上增加的。自然界的声音包括打破冰域，水下地震，和动物本身发出的声音。
水下测量的分贝值不同于在陆地上测量。１２０分贝的噪音在陆地上会使人类的耳朵感到疼痛。在水下，１９５分贝的声音会产生同样的效果。
有的科学家建议制定一个１２０分贝的海洋噪音限制。他们观察到，这种程度的噪音可以震慑鲸鱼并混淆其对周围环境的判断。
一组美国和加拿大的科学家发现更响的噪音会严重损害某些动物，研究小组发现，强大的水下爆炸造成了该地区的鲸鱼失去听力。这严重影响了鲸鱼交流信息并寻找路径的能力。有的鲸鱼甚至因为爆炸造成了耳朵流血，并发展为感染而死亡。
由于许多研究者的工作取决于海洋声音，他们反对这个１２０分贝的限制。他们认为这种限制将意味着重要工业和科技研究工作的结束。
科学家不知道多响的和什么样的噪音对海洋生物有害。然而，许多科学家怀疑噪声是比他们所认为的还要大的危险，他们想要防止噪声危害海洋动物。