Cities' contribution to global warming: notes on the allocation of greenhouse gas emissions

This paper suggests that the contribution of cities to global anthropogenic greenhouse gas emissions is often overstated. Many sources suggest that cities are responsible for 75—80 per cent of all such emissions. But as statistics drawn from the IPCC's Fourth Assessment show, this considerably understates the contributions from agriculture and deforestation and from heavy industries, fossil-fuelled power stations and high-consumption households that are not located in cities. It is likely that, worldwide, less than half of all anthropogenic greenhouse gas emissions are generated within city boundaries. However, if greenhouse gas emissions from power stations and industries are assigned to the location of the person or institution who consumes them (rather than where they are produced), cities would account for a higher proportion of total emissions. But it would be misleading to attribute this to “cities” in general, since these emissions would be heavily concentrated in cities in high-income nations and they should be ascribed to the individuals and institutions whose consumption generates them, not to the places where they are located.