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Supply Chain Emissions Make for a Bigger Carbon Footprint

The emissions needed to make and deliver consumer goods are a leading culprit of climate change

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A country's energy consumption of gasoline, coal and other fossil fuels is often the attention-grabber in climate discussions. But the energy to make and deliver consumer goods is a more hidden carbon culprit, a recent study says.

Steven Davis, a postdoctoral student in the Department of Global Ecology at the Carnegie Institute of Washington, tracked the supply chain of greenhouse gases from goods traded internationally in 2004. By following carbon emissions in more than 100 countries and 57 industrial sectors -- from the extraction of the fuels to the energy inputs in creating goods and services to delivery to the final consumer -- he and his colleagues uncovered a more complete story of who emits the world's greenhouse gases, and at which point in the supply chain.

"We are exposing this so that it's not as 'under the table,'" Davis said, "to just be clear about the disparate responsibility people need to share along supply chain." The best solution, he concluded, is to price carbon at its source. It would be just as effective as accounting for emissions higher up on the chain, he said.


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Davis and his colleagues found that the biggest fuel-burning countries may be the heaviest carbon emitters, but not necessarily have the biggest consumption footprint.

Once the researchers balanced the equation, they found that the world's biggest economies -- the United States, the European Union, the Middle East, Russia, China and Japan -- together account for 59 percent of the total difference between fossil fuel extraction emissions and emissions from the production of goods. When it came to consumption emissions, the margin was slightly higher, 64 percent, indicating that higher rates of consumption are tied to carbon emissions.

There were some exceptions to the rule. While China's consumption of fossil fuel emissions is relatively modest, its global manufacturing contributed 826 million tonnes of CO2 to Europe, the United States and Japan. Oil-rich but poverty-stricken countries also faced an imbalance.

"There's actually quite a gap among countries that are exporters," he said. "Some are petro states, like Nigeria, [that] haven't managed to export that for a robust economy."

Nevertheless, he argued the burden should be passed along the line, a view he hopes will resonate at the U.N. climate negotiations in Durban, South Africa, in December.

"If you look at the goods you're getting, it's a more complex situation," he said.

The findings have been published in the Proceedings of the National Academy of Sciences.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

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