City Pollution Mapped With Sound To Create Musical Landscapes
Researchers map pollutant compounds from air samples to create a sound spectrum, effectively hearing pollution in 'cleaner' and 'dirtier' California locations.
We know that pollution continues takes a toll on our health, environment and ecosystem, and while we can see effects such as smog, most of our sensory perception cannot grapple with or understand the pollutants in our immediate surroundings. Following this cue, researchers Aaron Reuben and Gabriel Isaacman of Yale Center for Environmental Policy and University of California – Berkeley, respectively, have created soundscapes of locations in California.
A soundscape is designed by taking air samples and first, using gas chromotograpy to separate the thousands of compounds in the air. Then, using mass spectometry, they plotted the chemicals based on structure. In more general terms, Reuben and Isaacman categorized the compounds and mapped them on a spectrum based on a ratio of mass-to-charge. By assigning tones to the compounds, they were able to ‘hear the pollution.’
To get a better idea of what these sounds are like and what they mean, the two researchers took air samples at different sites that are renowned either for high or low pollution. Whereas high pollution is signaled by a low droning sound (a sign of heavy hydrocarbons) or unresolved chords, cleaner air sounds higher in pitch and more frequently chirps.
Soundscape of the Caldecott Tunnel in Oakland, CA
Soundscape of the Sierra Mountains in Central Valley of CA
To hear more soundscapes and read more about the research process and findings, read ‘Soundscapes of Smog‘ by Reuben and Isaacman.