NC State Researchers Want To Hear Your Backyard For A New Mapping Project

Jan 28, 2019

Got a neighbor who loves to run their deafening leaf blower at full blast? Even if you don't, the noise pollution in your neighborhood could be impacting the health of people and nearby wildlife there.

Now, scientists at North Carolina State University are creating a map of the natural and man-made noises in Raleigh and Durham, and they want your help.

Subconscious Sounds

On a Wednesday afternoon in December, Durham's Trinity Park Neighborhood seemed pretty quiet from the roundabout where I stood. But when I turned on my microphone, my headphones came alive. Birds chirped in the trees above and around me. The pre-teen practiced tricks on her skateboard across the street. Lunch hour commuters whizzed down the thorough fares a couple blocks on either side of me. To the north, the highway vibrated with a low hum.

These are all the sorts of sounds being gathered for a new map of the Raleigh/Durham area.

We all know clean air and water are important to our health, and that developing the landscape can compromise that. But experts say sound affects us, even if we don't notice it.

"Even if a sound becomes familar to you and you no longer react to it, that sound can still be affecting your blood pressure, you heart rate, how rapidly you breathe," explained Kurt Fristrup, a branch chief for the National Park Service Natural Sounds and Night Skies Division. "This happens in animals as well as in humans."

The National Park Service has made a map of the natural and man-made noises on federal land and at airports. But Fristrup says the map doesn't have much data from residential urban areas, where a lack of quiet might also be a long-term health concern.

"Sound is an alerting stimulus," Fristrup said. "It's also sort of an activating stimulus in that when there are perceived threats or when an environment is potentially riskier because you can't hear as clearly, your body steps up to be on a higher level of alert and a higher level of readiness to react to potential threats."

Mapping the Noise

To document all that activating stimulus in the rapidly growing Triangle, Caren Cooper of NC State University and her team have launched a citizen science project called Sound Around Town. Raleigh and Durham residents can sign up to have staff notify their neighbors about the project, then periodically record the ambience in their neighborhood.

"Context really matters in what we can perceive," said Cooper. "A lot of anthropogenic sounds will mask natural sounds. Like if you're in a place that's super quiet, like a park, if an airplane flies overhead, you're gonna hear it for a longer time period and it's gonna seem really loud, whereas if you're in a really noisy city, you might not even hear the airplane."

What The Sounds Say

Cooper is a Research Associate Professor in Forestry and Environmental Resources. She says sound is relative, and that's why her team also asks participants to conduct listening sessions outdoors, notice what sounds they hear, whether or not they like them, and what they say about the place they're in. She says the map her team creates could have public health and environmental justice implications.

"As we learn more about those impacts of sound and help people understand those impacts," she said. "I mean, basically, it gives people leverage."

Cooper says the data will help supplement the National Park Service sound map, but it will also allow Triangle residents to be more proactive about how they cultivate their soundscape, for better or worse.