Bigger Is Not Always Better: A Comparative Analysis of Cities and their Air Pollution Impact

This paper investigates the pressure placed by cities on their environment with respect to urban air pollution. The analysis employs a spatially explicit global dataset of emissions to estimate urban emissions of four pollutants from a sample of 8038 cities world-wide in 2005. A cross-sectional regression analysis is then conducted to examine the association of urban air pollution with socioeconomic and geographical factors. The results confirm that urban pollution is associated primarily, but not exclusively, with demographics. The results suggest that urban pollution is likely to increase with population growth and that economic modernisation is unlikely to provide much relief from the pressures placed by coming population growth. The findings suggest that policy-makers must focus on reducing the emissions intensity of production activities within cities, especially from the energy sector, if they are to avoid rapid growth in urban air pollution in coming decades.