More than one-third of carbon-dioxide emissions linked to the consumption of goods and services in many developed countries are emitted outside their borders, according to a new study by scientists at the Carnegie Institution of Science.
The study also finds that about 2.5 tons of carbon dioxide is consumed per person in the U.S. and more than 4 tons per person in Europe, but the emissions are produced in another country. Most of these emissions are outsourced to developing countries particularly China, say researchers.
The study finds that the U.S. is both a major importer and exporter of emissions generated by traded goods with the U.S. outsourcing about 11 percent of its total consumption-based emissions primarily to the developing world.
Co-author Ken Caldeira, a researcher in the Carnegie Institution's Department of Global Ecology and lead author Steven Davis, also at Carnegie, used published trade data from 2004 to create a global model of the flow of products across 57 industry sectors and 113 countries or regions. The researchers calculated the net emissions "imported" or "exported" by specific countries by allocating carbon emissions to each product and source.
A key finding shows that products imported by developed countries of western Europe, Japan, and the U.S. cause substantial emissions in other countries particularly China; however, nearly a quarter of the emissions produced in China are ultimately exported. Researchers say China is the largest "exporter" of carbon-dioxide emissions among major exporting and importing countries.
One implication of emissions outsourcing is that consumer products that might be thought of as relatively carbon-free may be associated with significant carbon-dioxide emissions, says Caldeira.
The researchers note that regional climate policy needs to take into account emissions in trade not just domestic emissions.
The report is published online in the March 8, 2010 Proceedings of the National Academy of Sciences. (Subscription is required.)
A study from the Centre for International Climate and Environmental Research and Oxford University, supports the Carnegie scientists study, which found that emission reductions achieved by a number of industrialized countries is primarily due to the outsourcing of carbon intensive heavy industries to developing countries, reports BusinessGreen.com.
The Carnegie report is also likely to support China's long-term stance that consumers in the U.S., Europe and other developed countries should pay for carbon emissions from its factories.
