Pages

Dec 25, 2010

The Oceans Are Getting Louder

We all know carbon emissions are making our planet warmer. But the increase in carbon brings with it other surprising problems. More carbon apparently means low sounds travel farther underwater, making the ocean a noisier place to live and work.

The reason is complex. Increased atmospheric carbon dioxide also means increased absorption of carbon in the Earth's oceans. And this increase, in turn, means more acidic sea water. More acidic oceans mean less absorption of sound at low frequencies.

And less sound absorption means louder noises over longer distances. In a paper published in Nature Geoscience, scientists predict that, within 100 years, absorption of sounds at around 200 Hz will go down by 70%, meaning sound could travel much farther.

The effects of less absorption and more noise at this frequency could be huge. For instance, scientists and commercial shipping vessels use these lower range frequencies for navigation and oceanic research. Also, marine mammals, such as whales, use these low frequencies for finding food and mates. Noisier oceans might cripple ocean navigation and interfere with whale life.

Unfortunately, the acidification of the ocean won't end when we stop polluting. In fact, the acidic shallow waters will propagate into the deeper ocean, where sound travels farthest, and possibly spread this noisy effect much farther than expected.

Recently, scientists found that blue whale songs are changing, drifting lower in pitch. Their research hinted at the deep complexity of marine life and the in-progress nature of this kind of science. This new marine acoustics research puts an additional wrinkle in the world of underwater communication, making the story more complex and even more interesting.



9 comments:

Mister Sharaf said...

oh, this is interesting

mrecan said...

oh the world gets scarier every day

Mark said...

Wow, that's weird. I didn't know that was an added effect of their being more carbon...

Tango Anglo said...

Will somebody PLEASE think of the dolphins!!!

SuciƓ Sanchez said...

Quick - call Al Gore.
Blatant grant-trolling is blatant.

Teethree said...

this explains the dolphin that showed up at my house instead of his parent's for christmas.

NO DOLPHIN I DONT KNOW YOU

Tsipise said...

We might start talking with lower voices after a while.

Kingmush said...

Interesting effect...

Unablogger said...

quick heads up--this fool just copy/pasted your post word for word. Unless you did the same to someone else, I'd be pissed. If you pulled the same trick, well, then good luck. Just thought you should know.