It does. Diluted but it does. I think that 20% of the LA smog could be traced to be of Chinese origin. Sources - probably a guardian article an year ago.
That is clearly not feasible. Just think about it:
Right now, air quality index in central San Francisco is 15 [0]. That's "good". In central Los Angeles, it is 84, a "moderate" day [1]. Those figures are on linear scale [2].
The cities are about on an equal distance from China, and the figure for San Francisco is 18 % of that in LA.
If 20 % of Los Angeles pollution would be from China, then 110 % of San Francisco air pollution would be from China. Hey, it could only be 100 %. You took a bait.
tmospheric modeling shows that transport of the export-related Chinese pollution contributed 3-10% of annual mean surface sulfate concentrations and 0.5-1.5% of ozone over the western United States in 2006. This Chinese pollution also resulted in one extra day or more of noncompliance with the US ozone standard in 2006 over the Los Angeles area and many regions in the eastern United States. On a daily basis, the export-related Chinese pollution contributed, at a maximum, 12-24% 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 transboundary air pollution.
"3-10 % of annual mean surface concentration over Western USA" of a single pollutant is quite a different thing from "20 % of LA smog". By several orders of magnitude.
Yes, some pollutants are measurable over Western USA, at least in areas where there are no local pollutant sources.
