Make the invisible visible: reveal the magnetic field and air pollution to foster engagement in a community-based participatory research project

Abstract. Citizen science is increasingly recognized as essential for engaging the public in participatory sustainability research and for addressing the complex challenges of the Anthropocene. However, fostering meaningful dialogue between science and society remains difficult, often hindered by limited opportunities for interaction and varying levels of scientific understanding. Identifying outreach formats that foster citizen engagement and initiate productive exchanges between scientists and the public is therefore a key challenge. Here we present a hands-on science outreach workshop, based on environmental magnetism methods and conducted at schools and science fairs, that encourages citizen participation in air monitoring projects. We conducted the workshop between 2018 and 2023, reaching 850 people at 9 scientific outreach events and 195 children at 3 elementary schools. The workshop prompted more than 150 people to participate in the associated NanoEnvi community-based participatory research project, which offers to host passive biosensors in their homes or at school for a year. The workshop includes three hands-on demonstrations and experiences. It proposed to discover the magnetic phenomena, to extract airborne magnetic particles from soils, and to measure air pollution trapped on bark like a scientist. The workshop was also accompanied by lectures and an exhibition. We observed that the workshop fostered two-way dialogue between researchers and a wide range of participants, creating opportunities for shared experimentation and knowledge co-production. We found that the positive emotions raised by experimenting and playing with magnetic phenomena during the workshop led to engagement in a participatory project on potential air pollution in urban surroundings. Our findings demonstrate that hands-on geoscience outreach activities have a positive impact on the science-society dialogue.