Now that it is summer, I finally have some time to write about papers published this year that have been quite interesting. I’ll start here first with one published by Lin et al. in PNAS back in February that sought to calculate how much of the air pollution that wafts over to the US from China can be attributed to the stuff we buy from them…. that is, the pollution that is produced through the production of plastic do-dads and other things that we import and consume here. The authors looked at sulfur dioxide (a precursor to acid rain), nitrogen oxides (potent greenhouse gases), carbon monoxide, and black carbon (also implicated in climate change).
In total, they found that “about 21% of export-related Chinese emissions were attributed to China-to-US export”, indicating that one-fifth of their air pollution is driven by our consumption of their goods.
As for the pollution that wafts over to the US, Chinese pollution was sufficient to cause at least one additional day of ozone levels that violated US standards from Los Angeles to the eastern seaboard. In particular, a substantial proportion of sulfate pollution measured in the western US was attributable to Chinese exports.
Quite a few years ago, my colleagues and I wrote about the way that international trade can complicate consumption impacts on the environment…. specifically how the international wood trade can hide the link between wood consumption and deforestation. One of the consequences of our increasingly international economies is our growing blindness to how we impact our environment (which is now global as well). Prior to the Industrial Revolution, production and consumption were mainly local to regional; product availability was closely tied to regional weather, soil, and human labor. Prices could reflect these conditions and overall supply, including how that supply impacted the quantity and quality of resources such as water, air and soil. Now that our economy has globalized, we need to find better ways to allow product data and prices to once again reflect the environmental capacity of the system, so that we can better understand the impacts of our consumption. Lin et al.’s paper nicely illustrates why we should care about pollution in China; our environments are as connected as our economies, and negative environmental impacts elsewhere have a way of “boomeranging” back to us.