Listening to Manchester: Using citizen science Raspberry Shake seismometers to quantify road traffic

Road traffic is a major contributor to greenhouse gases in our cities. This study has been designed to test whether low-cost citizen science seismometers (Raspberry Shakes) can be used to quantify temporal and spatial variations in road traffic. I used a network of seismometers installed around Greater Manchester to record signals in the frequency range 1-50 Hz. Data were processed using the open source ObsPy package. Results show that daily variations in seismic noise in this frequency range correlate directly with vehicle counts from open access traffic cameras installed nearby. In addition, a simple peak-counting method can be applied to the seismometer recordings to measure individual passing vehicles, which correlate directly with in-person traffic counts. Two seismometers were installed close to a School Streets pilot project to test if traffic volumes increased just outside the road closure section. Results to data show no increase in seismic vibrations attributable to road traffic, over 6 road closure days. The combination of low unit cost and transparent (i.e., open) data from these seismometers makes them a useful tool to simultaneously quantify anthropogenic noise – including road traffic – and share the results with the wider public.