The high-latitude oceans could become an increasingly noisy place to live this century, according to a study published online in Nature Geoscience. Increased noise levels could influence the behaviour and biology of marine organisms, for example causing the temporary loss of hearing in dolphins or the mass stranding of cetaceans.
Low-frequency sound in the ocean is produced by natural phenomena, such as rain, waves and marine life, and by human activities such as sonar systems, shipping and construction. The concentration of chemicals that absorb sound in the world's oceans has declined as a result of ocean acidification, in turn caused by rising concentrations of carbon dioxide. Tatiana Ilyina and colleagues use model simulations to show that reductions in ocean pH could reduce seawater sound absorption by as much as 60% at high latitudes and in areas where deep water forms.
This could affect species at the top of the ocean food web ― for example, baleen whales ― by changing the spread of sound in the oceans.