Noise Pollution: Why We Should Embrace It

There is no doubt that America is noisy. But rather than blocking out the sound of blaring car horns, airplane engines and the whir of machinery, researchers suggest that we embrace it.

At the annual meeting of the American Association for the Advancement of Science on Monday, scientists with the National Park Service presented a map of noise levels across the country. In order to determine the quietest and loudest places in the United States, they used 1.5 million hours of acoustical monitoring from places as remote as Dinosaur National Monument in Utah to areas as urban as busy New York City.

It comes as no surprise that urban areas such as Los Angeles and Dallas are the loudest, boasting noise levels of 50 decibels (dB) or more. And if you're craving quiet, large swaths of the West stay below 20 dB, akin to levels prior to European colonization. According to its definition, the normal human ear can detect sounds that range between 0 dB and about 140 dB, which is when things get painful.

It's easy to recommend simply avoiding the cacophony, but in this day and age, quiet is hard to come by.

"Both noise and light pollution are growing far faster than the human population of the United States," Kurt Fristrup, a senior scientist at the National Park Service, told NBC News. "They're somewhere between doubling and tripling every 20 to 30 years."

To drown out the background noise, people use things like earplugs and noise-cancelling headphones, but our efforts to avoid noise pollution might actually be making it worse - and could cause a phenomenon called "learned deafness."

"This learned deafness is a real issue," Fristrup told The Guardian. "We are conditioning ourselves to ignore the information coming into our ears."

"There is a real danger, both of loss of auditory acuity, where we are exposed to noise for so long that we stop listening, but also a loss of listening habits, where we lose the ability to engage with the environment the way we were built to," he added.

Fristrup compares learned deafness to the effect fog has when you're peering into a landscape. You only see a portion of what's in front of you.

"Even in most of our cities there are birds and things to appreciate in the environment, and there can be very rich natural choruses to pay attention to. And that is being lost," he warned.

The fear is that if humans keep shielding themselves from noise pollution, overall noise is going to crescendo to a point that we will no longer know what a quiet environment is.

Overwhelming Wildlife

And this isn't just bad news for humans. Wildlife species are affected by noise as well. For animals such bats and owls, whose ears are up to 20 decibels more sensitive than human ears, man-made sound drowns out the faint rustles of insects and rodents they need to hunt, the scientists say.

Other land-based animals also try to tune us out, including prairie dogs who are driven underground by traffic noise. And birds, which rely on a "magnetic compass" for their sense of direction, are disturbed by electromagnetic noise interference from our electronics.

But noise pollution can also go below the surface. Marine life is just as susceptible to the discord that happens on land. Sea hares, for one, are shown to die off and cease embryonic development when exposed to boat noise. (Scroll to read on...)

Whales are the more obvious and concerning species when it comes to noise pollution. Scientists just recently came to understand the mechanics of how these massive mammals hear so well, even while deep underwater. It turns out that sound quite literally resonates deep in their bones (at least for baleen whales) enabling supersensitive hearing that can stretch for miles. However, their remarkable ears also pick up sounds other than the majestic songs of their peers.

Boat traffic and other sonar-emitting devices like those that the US Navy uses is raising concerns among conservationists that it could threaten marine life, including endangered whale species. In fact, recent research found that whales were far less stressed post 9/11 because nonessential boat traffic was halted around the United States. After these horrific attacks, the whales temporarily got back their peace and quiet.

"These signals are quiet, but they are audible to the animals, and they would be relatively novel since marine mammals don't encounter many sounds in this range," marine mammal expert Brandon Southall said in a statement.

Most sonar devices transmit at signals near the 200-kilohertz (kHz) frequency, however some sonar systems emit signals as low as 90, 105 and 130 kHz - noises known to be within the cetacean's (whales, dolphins, etc.) hearing range.

According to Cal Poly biologist Clinton Francis, even plant species are suffering from noise, which drives away the animals that play a role in spreading their seeds.

"It appears as though noise pollution is causing a large-scale decline in pinyon pine seed dispersal," he told NBC.

Nature Calls

Not only does noise harm wildlife but it also makes us oblivious to Mother Nature's beautiful calls. The tranquil chorus of trickling water and birds chirping is lost as we reach for our iPods on the walk to work. And these pure sounds are not just more pleasant to listen to than traffic, but they may also benefit human health. (Scroll to read on...)

Preliminary research presented at Monday's meeting shows that recordings of sounds from national parks likely have the power to help us recover after stressful events. Researchers think, The Guardian reports, that evolution might have something to do with it. During the time of our ancestors, the peaceful chatter that we now ignore may have signaled safety in the absence of predators, and on some level we still believe in that association.

But will we forever drown out Mother Nature?

"One of the great hopeful things about this particular area is that mitigation can be immediately effective," Fristrup noted.

The Sounds of Silence

Scientists are working out ways to keep things quiet. For example, the National Park Service developed a noise mitigation plan for Yellowstone National Park that rewards tour guides if they find quieter ways to show people the sights.

Noise pollution has all kinds of negative effects, but blocking it out can be just as bad for us. Learning to embrace it may be the better option, however it is a fine line when considering its impact on wildlife.

So the next time you're walking to work with your headphones, turn off the music and instead listen to all the beautiful sounds that nature has to offer.

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