Begin with the current inventory of carbon dioxide emissions – CO2 being the principal greenhouse gas generated almost entirely by energy use. According to the Department of Energy’s most recent data on greenhouse gas emissions, in 2006 the U.S. emitted 5.8 billion metric tons of carbon dioxide, or just under 20 tons per capita. An 80% reduction in these emissions from 1990 levels means that the U.S. cannot emit more than about one billion metric tons of CO2 in 2050.
Were man-made carbon dioxide emissions in this country ever that low? The answer is probably yes – from historical energy data it is possible to estimate that the U.S. last emitted one billion metric tons around 1910. But in 1910, the U.S. had 92 million people, and per capita income, in current dollars, was about $6,000.
By the year 2050, the Census Bureau projects that our population will be around 420 million. This means per capita emissions will have to fall to about 2.5 tons in order to meet the goal of 80% reduction.
It is likely that U.S. per capita emissions were never that low – even back in colonial days when the only fuel we burned was wood. The only nations in the world today that emit at this low level are all poor developing nations, such as Belize, Mauritius, Jordan, Haiti and Somalia.
Read the whole thing in Monday’s Wall Street Journal.