Consumption-based accounting of CO ₂ emissions

TLDR

CO₂ emissions from fossil fuel combustion drive global warming, yet most studies focus on country‑level direct emissions rather than the emissions linked to consumption of goods and services, which differ due to international trade. The study aims to present a global consumption‑based CO₂ emissions inventory and calculate associated consumption‑based energy and carbon intensities. The authors use the latest available data to compile the inventory and perform the calculations. In 2004, 23 % of global CO₂ emissions (6.2 Gt) were traded internationally, mainly as exports from China and other emerging markets to developed countries; wealthy nations imported over 30 % of their consumption‑based emissions, with net imports exceeding 4 t CO₂ per person in Europe and 2.4 t in the U.S., while China exported 22.5 % of its emissions, illustrating potential international carbon leakage and suggesting shared responsibility could aid global climate policy.

Abstract

CO 2 emissions from the burning of fossil fuels are the primary cause of global warming. Much attention has been focused on the CO 2 directly emitted by each country, but relatively little attention has been paid to the amount of emissions associated with the consumption of goods and services in each country. Consumption-based accounting of CO 2 emissions differs from traditional, production-based inventories because of imports and exports of goods and services that, either directly or indirectly, involve CO 2 emissions. Here, using the latest available data, we present a global consumption-based CO 2 emissions inventory and calculations of associated consumption-based energy and carbon intensities. We find that, in 2004, 23% of global CO 2 emissions, or 6.2 gigatonnes CO 2 , were traded internationally, primarily as exports from China and other emerging markets to consumers in developed countries. In some wealthy countries, including Switzerland, Sweden, Austria, the United Kingdom, and France, >30% of consumption-based emissions were imported, with net imports to many Europeans of >4 tons CO 2 per person in 2004. Net import of emissions to the United States in the same year was somewhat less: 10.8% of total consumption-based emissions and 2.4 tons CO 2 per person. In contrast, 22.5% of the emissions produced in China in 2004 were exported, on net, to consumers elsewhere. Consumption-based accounting of CO 2 emissions demonstrates the potential for international carbon leakage. Sharing responsibility for emissions among producers and consumers could facilitate international agreement on global climate policy that is now hindered by concerns over the regional and historical inequity of emissions.