Taking our reported annual emissions and the size of the U.S. population, the average American is responsible for about 17 tons of carbon dioxide emitted to the atmosphere each y ear—among highest per capita emissions in the world. About 1/3 of our emissions stem from transportation, largely personal automobiles. About 37% of our emissions are associated with the generation of electricity. The remaining emissions are attributed to industry, residential use, and agriculture.
Overall emissions in the United States peaked in 2008 and have trended downward in more recent years—something we can rejoice about. And they are poised to drop even further with the institution of the Clean Power Act by the Obama administration, which aims to reduce emissions in 2030 to 32% below 2005 levels. Most of the reduction is sought by reducing the use of coal to generate electricity. Progressive increases in the fuel efficiency standards for automobiles are also destined to lead to lower emissions from the transportation sector in the coming years. The U.S. should arrive at the next international conference on climate change with some good success stories to tout.
One aspect of our declining emissions is masked in the nation’s reports. As we see a large amount of manufacturing shift to China and other Asian countries, what we once emitted here no longer shows up on our balance sheet. It shows up on the balance sheet of our trading partners. In our house nearly everything we buy is made in China or assembled overseas. No wonder our carbon dioxide emissions from manufacturing are dropping.
One recent study indicates that our emissions would be about 18% higher if we made everything at home. Indeed, in some cases through known efficiencies, we could manufacture goods at home with lower emissions than we cause abroad. But we buy from abroad because the savings on labor costs overwhelm the costs of energy, even when foreign factories are less efficient than ours.
These exported emissions are largely immune from various schemes, such as cap-and-trade programs and carbon taxes, which are proposed to lower our nation’s contributions to rising carbon dioxide in the atmosphere. Some form of tariff on imported goods could be part of a domestic carbon tax program to lower our nation’s emissions. I doubt this would be popular with many voters, but we need to move forward with all measures to limit the future extent of rapid changes in the global climate.
No doubt a lot of goods are sold in the U.S. at lower prices than we would find if we made them at home. But, the hidden costs of our imports on the atmosphere need to be part of our accounting. The recent, downward trend in our CO2 emissions, resulting from our desire to buy goods from abroad, does not help the global environment.
Davis, S., J., G.P. Peters and K. Caldeira. 2011. The supply chain of CO2 emissions. Proceedings of the National Academy of Sciences, USA. 108: 18554–18559,
Jakob, M. and R. Marschinski. 2013. Interpreting trade-related CO2 emission transfers. Nature Climate Change 3: 19-23
Peters, G., J. Minx, C.L. Weber, and O. Edenhofer. 2011. Growth in emissions transfers via international trade from 1990 to 2008. Proceedings of the National Academy of Sciences, USA 108: 8903-8908.