The transport of Asian dust and combustion aerosols and associated ozone to North America as observed from a mountaintop monitoring site in the California coast range

We present data from Chews Ridge, a remote mountaintop site in California, in February-September 2012, which identifies separate Asian dust and Asian combustion aerosol signals and quantifies exogenous ozone. We use positive matrix factorization of size-fractionated aerosol X-ray fluorescence data and Pb-206/Pb-207 and Pb-208/Pb-207 isotope measurements to isolate aerosol signals of Asian origins and find good agreement between both types source attribution techniques.

Power spectra of Asian dust and Asian combustion signals reveal two distinct peaks, one seasonal (similar to 90days) and one monthly (similar to 25-30days). Overall, 89% of the Asian dust signal occurs in March-May, compared with June-September, whereas only 51% of the Asian combustion signal occurs in March-May. Nearly half the Pb observed at Chews Ridge was derived from Asia (46%; 8.3% from Asian dust, 23% from Asian combustion, and 15% of the Asian Pb signal was not explained by the positive matrix factorization).