Sons al Balcó, a Citizen Science Approach to Map the Soundscape of Catalonia

Sons al Balcó (Catalan for "Sounds from the balcony") was a project born to study the effect that the COVID-19 pandemic lockdown caused on the perception of noise in Catalonia. One of the aims of the project was to combine the research activities - acoustic and image processing, urbanistic analysis and health and annoyance evaluation - with the dynamic collaboration with citizens and other stakeholders to create social and environmental impact, to raise awareness and design tools to improve citizenship development and empowerment. This first year of Sons al Balcó has shown that citizens are willing to participate in initiatives that work with their everyday life, because one year after the lockdown, a new soundscape map of Catalonia has been built with their collaboration and their perceptual impact from their balconies or windows. This has allowed the inclusion of other issues that enhance the final goal of describing and finding relationships between the annoyance caused by noise, and other factors as the environment (urban, suburban, rural) and the landscape, including the soundscape and noise levels in this evaluation. Objective measurements of LAeq have been conducted during the lockdown and in the months afterwards to describe the average noise and its possible link with outdoor activities. During this second collecting campaign, Sons al Balcó managed to gather more than 220 contributions. In this work, we detail the definitions of the metrics that include urbanistic and health-related environmental elements (water, trees, etc.), together with the socio-economic and demographic data that correspond to the answers of the questionnaires, and finally, the information extracted from the audios and the videos sent by the citizens. Preliminary results show encouraging dependencies between perception gathered with the questionnaires and the objective data collected, with a clear bias when related to the type of environment (rural, urban or suburban).