There is a strong correlation between carbon footprint and income level, both domestically and internationally.
The US Census has produced a report (P23-202) titled “Supplemental Measures of Material Well-Being” which includes an analysis of the relationship between income and household energy use (Table 8). This analysis indicates that households with incomes over $75,000 (at 124.7 million BTUs) consume almost twice the energy used in households with incomes under $10,000 (at 65.2 million BTUs). Households with incomes between $50,000 and $75,000 consume 102.5 million BTUs as compared to a national average 92.2 million BTUs.
These numbers do not include transporation energy use, just in-home use, but the same report shows at Table 5, that the number of motor vehicles owned ranges from 0.6 for the poorest ten percent of the consuming units to 2.4 for the richest ten percent.
The Travel Industry Association estimated that in 2002, 76% of the approximately 1 billion person-trips by air in the United States were for pleasure or personal reasons, while another 8% were for mixed business and personal reasons. Clearly, the air travel segment of the nation’s footprint (9.8% of the total emissions from transportation) must be heavily weighted to the more affluent.
While households with more limited income may be unable to afford the newest, most-efficient appliances and vehicles, it seems clear that households in the upper income brackets, occupying larger floor area, driving more vehicles and travelling more and further for pleasure have significantly larger carbon footprints.
At the national level, the richest nations have vastly larger per capita carbon footprints than the poorest. This correlation is somewhat diluted by deforestation in the poorest countries. The scatter graph below plots CO2 emissions per capita (excluding deforestation) and GNP per capita in 2003 for the 40 largest population countries. The point on the high far right is the United States and the point on the low far left (close to the origin) is the Congo. The listing of points appears further below. The source of these statistics is cait.wri.org.
|Congo, Dem. Republic||620||0|
|European Union (25)||23,770||8.8|
|United States of America||35,373||19.9|