From: Tanya Dimitrova, MONGABAY.COM, More from this Affiliate, ENN.com
The average American car weighs about 3,000 pounds. But to produce that
vehicle, a lot more raw materials were used than its final weight! Maybe as
much as 100 times more, as reported by scientists in a recent paper in the
Proceedings of National Academy of Science.For this car to be produced, iron ore is mined in Australia and made into steel. Steel is then shipped to Japan and made into a car, which is then sold in the U.S. Most studies until now, measured national consumption by accounting only for the final weight of the products we purchase.
"The rock where the iron was mined never leaves Australia," says Thomas Wiedmann, the lead researcher, so it was not included in the account. But the scientist and his colleagues showed that most of the raw materials for producing the stuff we use are actually extracted overseas, so they could no longer be ignored. In the case of this car, they allocate the weight of the iron ore mined in Australia to the U.S. consumer who bought the vehicle.
Using this new accounting, it turns out that on average, each of us in the U.S. uses 25 tons of raw materials every year to produce our stuff and our energy. That is the weight of about 20 cars. By comparison, the average Chinese person uses 12 tons and the average Indian only 4 tons of raw materials per year.
Take another example: a newly built call center in India. The cement might have come from China, the glass was possibly sourced locally in India, but the whole purpose of the call center is to provide customer support to an American retail company. Who does that material footprint belong to? — The U.S. customers, according to the scientists.
The researchers came up with the term "material footprint" as an analogy to "carbon footprint" (that is, how much carbon emissions is each person accountable for). In this case, the personal material footprint measures how much raw materials extraction is each consumer responsible for. The top three raw materials turn out to be metal ores (e.g. iron, copper), fossil fuels for energy (coal mining) and construction materials (e.g. cement).
Continue Reading at Mongabay
Mining via Shutterstock
