Global interdependence now means not only sharing the same warming atmosphere - but also breathing the same air.
A recent groundbreaking study led by Chinese and American scientists, published in the Proceedings of the National Academy of Sciences (PNAC), documents how pollution from US- outsourced manufacturing in China blows back to California and the West Coast. The report echoes The WorldPost contribution by Frank Ackerman.
On a daily basis, the PNAS report concluded, export-related Chinese pollution contributed as much as 24% of sulfate concentrations over the western United States: "As the United States outsourced manufacturing to China, sulfate pollution in 2006 increased in the western United States but decreased in the eastern United States, reflecting the competing effect between enhanced transport of Chinese pollution and reduced US emissions. Our findings are relevant to international efforts to reduce trans-boundary air pollution."
Though quite technical, you can read the details of the report here: http://www.pnas.org/content/early/2014/01/16/1312860111.full.pdf