Cloud Water Chemistry Measured at Mt. Bamboo in East Asia since 1996

Wintertime cloud water collection on an hourly basis for each event was conducted at Mt. Bamboo (~1,100 m MSL) in northern Taiwan since 1996. About 150 events of more than 5,000 samples were obtained. The cloud water chemistry is comprehensively characterized. In general, the cloud events can be categorized into two cloud types, which are associated with northeast monsoon flows and frontal passages. The average pH for all events ranged in 3.2-5.8. On average, the dominant ions in collected cloud water were Na+, Cl-, SO42-, NO3-, and NH4+. The first two seasalt ions generally can account for more than 50% of total ion concentration. In addition to the statistic analysis, the parameters of Acidifying Potential (AP), Neutralizing Potential (NP) and Seasalt Potential (SP) are used to characterize the cloud water chemistry. The source/receptor relationship between source regions and cloud water chemistry is further studied. Results indicates that regional air pollutants can be possibly carried through clouds to Taiwan via the long-range transport. The impact of Asian dusts on cloud water chemistry will be also discussed.