Tipping Points Toward Urban Pollution Advantage? Scaling of Carbon Dioxide Emissions in the US Urban Areas

Abstract

The relationship between size of cities and energy use and carbon dioxide emissions has become an important research topic with the accelerated urbanizations. Results from previous empirical analyses have diverged greatly on the relationship between population and carbon emissions. In this study, we investigate the dataset of city size and carbon dioxide emissions for 933 urban units in the U.S. in order to identify the scaling effects of population size on carbon dioxide emissions. The results of carbon dioxide emission across urban units in the U.S. show that larger size cities display much more significant scaling advantages in comparison to smaller size cities. Moreover, we find that the tipping point for urban pollution advantage occurs around the population size of 680,000.