Trade effects of alternative carbon border-tax schemes

In industrial countries contemplating emissions reductions, there have been calls for additional border taxes on imports from countries with lower carbon prices. A key factor affecting the impact of any border taxes is whether they are based on the carbon content of imports or the carbon content of domestic production. Our quantitative estimates suggest that the former action when applied to all merchandise imports would address competitiveness and environmental concerns in high-income countries but with serious consequences for trading partners. For example, China's manufacturing exports would decline by one-fifth and those of all low- and middle-income countries by 15 %; the corresponding declines in real income would be 3.7 and 2.4 %. Border tax adjustment based on the carbon content in domestic production would broadly address the competitiveness concerns of producers in high-income countries and less adversely affect developing country trade.