One way of attributing greenhouse gas emissions is to measure the embedded emissions—also referred to as “embodied emissions”—of goods that are being consumed. Emissions are usually measured according to production, rather than consumption. For example, in the main international treaty on climate change (the UNFCCC), countries report on emissions produced within their borders such as the emissions produced from burning fossil fuels. Under a production-based accounting of emissions, embedded emissions on imported goods are attributed to the exporting, rather than the importing, country. Under a consumption-based accounting of emissions, embedded emissions on imported goods are attributed to the importing country, rather than the exporting, country.
A substantial proportion of CO2 emissions are traded internationally. The net effect of trade was to export emissions from China and other emerging markets to consumers in the US, Japan and Western Europe. On a per-capita consumption basis, the top-5 emitting countries were found to be Luxembourg (34.7), the US (22.0), Singapore (20.2), Australia (16.7) and Canada (16.6).
Carbon Trust research revealed that approximately 25% of all CO2 emissions from human activities ‘flow’ (i.e. are imported or exported) from one country to another. Major developed economies were found to be typically net importers of embodied carbon emissions.
This project focuses on the flow of embodied emissions between the US and China.
Source: Davis, S.J., G.P. Peters and K. Caldeira (2011). The Supply Chain of CO2 Emissions. PNAS www.pnas.org/cgi/doi/10.1073/pnas.1107409108