[LUM#6] Citizens and Scientists
A citizen science project to measure air quality: when researchers and citizens join forces, science moves forward… and everyone benefits.
September 2015: A coalition of 23 organizations supporting Tram Line 5 reached out to the research community. This group of hundreds of citizens asked themselves: Is the air cleaner along tram tracks than along roadsides? One of its members had heard about a British study on fine particulate matter deposited on vegetation near roads. It was a new method for measuring air quality, still rarely used, but apparently reliable. The equipment used belonged to Pierre Camps of the Geosciences Laboratory. Without hesitation, the organizations decided to reach out to the researcher.
Shared knowledge
“They had to call me several times before I agreed… Air quality isn’t my usual area of research ,” explains this specialist in rock magnetism. He finally decided to take the plunge. But for this unfunded study, he needed resources. So he asked about sixty citizens to collaborate directly. A prime example of citizen science was born. In January 2016, each volunteer was trained individually… And the work could begin. For six months, the volunteers collected leaves from eleagnus, holm oaks, ivy, and even laurel or oleander. Trees and shrubs clearly identified for each collector, for example near their workplace or in their garden. Samples poured into the lab, coming from an area stretching from Cournonterral to Clapiers and Montferrier, via Montpellier. Scientists then analyze the leaves. But they want to ensure that the collectors are following protocol. So they replicate the measurements on their own, in a few areas. Verdict: the leaves were collected flawlessly. Everyone played along perfectly.
“We collected a thousand data points in six months. We could never have done that without the volunteers. For a researcher, this kind of collaboration is ideal,” says Pierre Camps. It’s an impressive achievement, but also a sharing of knowledge.“We researchers are stepping outside our usual boundaries. It’s very enriching. I’ve learned a lot from discussions with the volunteers—who are very knowledgeable and well-educated—for example, about fine particulate matter or botany. There is a wealth of knowledge in society, and researchers have a personal interest in shared knowledge.”
Constructive responses
What were the study’s findings? There aren’t necessarily fewer fine particles in the vicinity of the tram (La Marseillaise, 2016). This is the opposite of what people had imagined! The reason is likely the wear and tear on the tram’s wheels, brakes, and tracks.“A tram wheel loses 10% of its size over its lifetime. The wheel literally turns to dust; we breathe it in!” explains Patrick Nicol, volunteer coordinator. The engaged citizens weren’t disappointed, however… Above all, they wanted constructive answers.
On the topic of air quality, citizen science continues. A project is launching in Saint-Aunès to study the impact of the A9 highway expansion and the effect of green walls. While this type of collaboration with citizens is still extremely rare in earth sciences, Pierre Camps has plans. In his laboratory, he is helping to create a new group focused on “geophysics and society.” To continue enriching one another.
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