Air Hotspots: High-Resolution Air Pollution Mapping with Google Street View Cars

By: Emily Gonzalez

Air pollution is one of the most harmful and major risks for human health and the environment. For this reason air pollution measurements are pivotal for epidemiology and air quality management. However, the pollution measurements are limited or absent for most of the world, and if they are available they are not as effective since they lack spatial resolution, and localized pollution hotspots. A research done by Apte et al. focused on reducing the current limitations for mobile air pollution sampling through the use of equipped professionally driven fleet vehicles with air quality instruments, that continuously sample every street of an urban area, and apply date reduction algorithms in order to transform long term spatial patterns from the data gathered.

Methods Used

The study was done over the course of 1 year, it took place in three main areas of Oakland, CA: West, East and Downtown. Two Google Street View mapping vehicles were equipped with an Aclima environmental intelligence fast-response pollution measurement and data integration platform, the areas were sampled within a measurement of 30 km2, and measured weekday and daytime concentrations of black carbon particles (BC), NO, and NO2.  The drivers were instructed to only drive every road at least once and to drive at normal flow of traffic, in a 1-5 km2 distance. The results indicated that air pollution is existent at finer scales than what is currently being detected by conventional methods. It was shown that weekday daytime primary pollutant levels vary by up to 2-8x or more within neighborhoods. The median concentrations of BC, NO, and NO2 were 32%, 61%, and 35%, respectively.

This study demonstrated an effective and pragmatic approach to measure air pollution. The overall costs are similar to those in practice, but the results are much more accurate with better spatial information, and lower temporal resolution. This availability of higher resolution air quality data can greatly impact the world by changing the way air quality is measured and managed, raising public awareness, and epidemiology, also by localizing pollution hotspots that would lead to pollution control.

Reference

Apte, J.S., K.P. Messier, S. Gani, M. Brauer, T.W. Kirchstetter, M.M. Lunden, J.D. Marshall, C.J. Portier, R.C.H, Vermeulen, and S.P. Hamburg. 2017. High-Resolution Air Pollution Mapping with Google Street View Cars: Exploiting Big Data. Environ. Sci. Technol. 51,12:6999-7008.