Moving beyond the noise: geospatial modelling of urban sound environments in a sub-Saharan African city.

Journal: Scientific reports
Published Date:

Abstract

Cities encompass a mixture of artificial, human, animal, and nature-based sounds, which through long and short-term exposures, can impact on physical and mental health. Yet, most epidemiological research has focused on only transportation noise, leaving a significant gap in understanding the health impacts of other urban sound types, especially in sub-Saharan Africa (SSA). We conducted a large-scale measurement campaign in Accra, Ghana, collecting audio recordings and sound levels from 129 locations between April 2019-June 2020. We classified sound types with a neural network model and then used Random Forest land use regression to predict prevalences of different sound types citywide. We then developed a composite metric integrating sound levels with the prevalence of sound types. Road traffic sounds dominated the urban core, while human and animal sounds were prominent in high-density and peri-urban areas, respectively. Our high-resolution approach provides a comprehensive characterization of the complexity of urban sounds in a major SSA city, paving the way for new epidemiological studies on the health impacts of exposure to diverse sound sources in the future.

Authors

  • Sierra N Clark
    Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK.
  • Raphael E Arku
    Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts, Amherst, USA. rarku@umass.edu.
  • Majid Ezzati
    School of Public Health, Imperial College London, London, UK.
  • James Bennett
    NIHR In Practice Fellow, Hull York Medical School, University of Hull, Hull HU6 7RX, UK.
  • Ricky Nathvani
    Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK.
  • Abosede Sarah Alli
    Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts, Amherst, USA.
  • James Nimo
    Department of Physics, University of Ghana, Accra, Ghana.
  • Josephine Bedford Moses
    Department of Physics, University of Ghana, Accra, Ghana.
  • Solomon Baah
    Department of Physics, University of Ghana, Accra, Ghana.
  • Allison Hughes
    Department of Physics, University of Ghana, Accra, Ghana.
  • Samuel Agyei-Mensah
    Department of Geography and Resource Development, University of Ghana, Accra, Ghana.
  • George Owusu
    Institute of Statistical, Social and Economic Research, University of Ghana, Accra, Ghana.
  • Mireille Toledano
    Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK.
  • Michael Brauer
    University of British Columbia, School of Population and Public Health, Vancouver, BC, Canada.