Carbon Dioxide Emissions Per Household Within Counties
Full Size Map
(PDF, 63 KB)
This map again draws on 1999 data from the U. S. Federal Highway Administration. However, it divides the vehicle miles traveled by the number of households per county, showing lower emissions in the most densely populated areas. This is because the average household in a dense community drives less, or shorter distances, than a household in a suburban or rural community. So, while densely populated counties such as the San Francisco or Chicago regions may have higher total emissions, they have lower emissions per household than less densely populated areas.
One explanation for the difference between rural and urban driving emissions is that households in urban areas tend to have multiple transportation options for a given trip. Transit is much more common in urban areas because higher populations increase ridership. Also, when destinations are closer together, people not only need to drive shorter distances, but they can also walk or bike. Regional planning decisions that recognize the importance of public transportation help to lessen the effects of climate change and improve the health of communities.
