Methane embodied in the international trade of commodities: Implications for global emissions

Abstract

Countries are now setting goals seeking to limit emissions of carbon dioxide (CO 2), and many countries are also addressing measures to control methane (CH 4), the next most important gas after CO 2. Current methods for estimating domestic greenhouse gas emissions do not take into account CH 4 and other gases released abroad when producing the imported goods. In this paper, the amount of CH 4 that is currently released in countries that have not adopted greenhouse gas emissions targets to produce exports consumed in countries that have pledged to stabilize or reduce CH 4 emissions, is analysed. Commodity trading in 1990 that involved the most CH 4 intensive agricultural goods — rice, meat, and milk products — is assessed for six developed countries, the USA, UK, Germany, Japan, France and Canada. The amount of CH 4 ‘embodied’, or released in exporting countries while producing the goods traded with these six countries, is calculated. The total amount of CH 4 embodied in imports from developing countries for these six nations in 1990 is estimated to be nearly 1200 kt, about 7% of emissions from livestock for these importing countries, and 9% of emissions from rice produced within the importing countries own borders. This level is greater than domestic anthropogenic CH 4 released from all sources for most countries (103 out of 140 countries surveyed). The UK is the greatest importer of CH 4 embodied goods, with imports of agricultural products equivalent to 23% of emissions from these agricultural sources. While currently the CH 4 released in producing imports to these countries is small, the rate could grow considerably in the future. Factors that will influence this growth include removal of traditional subsidies and levies in Europe, Japan, the USA and in some developing countries. As developing country livestock production becomes more competitive, the opportunity for trade in CH 4 embodied products is likely to increase. Possible circumvention of national CH 4 targets could be controlled by changing the methodology for estimating national greenhouse gas emissions so that trade is taken into account. The more practical and equitable approach is to extend greenhouse gas emissions targets to all countries participating in the climate convention, using an emission trading scheme or an international funding mechanism for transferring resources.