Who Should Pay for Outsourced Emissions?

In 2004, 22.5 percent of China's carbon dioxide emissions from fossil fuels went toward the manufacture of goods for export. Is China responsible for these emissions, or should consumers bear some of the burden?

Emissions outside the United States for U.S. consumption represent the equivalent of 11 percent of U.S. per capita CO2 emissions. Are U.S. trade partners responsible for this portion, or do U.S. consumers share responsibility?

In an effort to start to answer that question, a new paper by Ken Caldeira and Steven Davis breaks emissions down based on who consumes products rather than who produces them. One result of the study's detailed efforts to analyze where emissions result from the things we buy is a map (below) where almost all roads lead to the United States and Europe.

The easy answer to the question "who's responsible" is that we all are; CO2 emissions know no borders. But international agreements don't work well with easy answers. A better accounting of the results of consumer action can bring less developed countries to the table and buttress the "common but differentiated responsibility" principle, which is essential to international climate agreements.

Chinese discussions of emissions regulation for years have included the idea that some of the emissions in China are ultimately the result of consumer behavior elsewhere, an idea that some negotiators for rich countries have opposed.

There are two reasons from the U.S. perspective to support consumption-based emissions accounting in international agreements. The first is political. A truly binding commitment from diverse countries is more likely if less developed countries know they will not be saddled with responsibility for emissions related to products developed countries consume. The second is more simple. Consumption-based accounting is basically an aggregate of the idea of consumer responsibility.

These methods of accounting are developing, and the new paper is one step toward the complex statistical methods we will need. Let's hope the political side catches up.

Arrows represent trade flows, and the thickness of the line represents the amount of emissions in the exporting country. Units are megatons of CO2.

Photo credit: High Contrast