Atmospheric carbonyl compounds in Chinese background area: A remote mountain of the Qinghai-Tibetan Plateau

[1] The ambient concentrations of carbonyl compounds were measured in Waliguan (WLG) Observatory at the east edge of Qinghai-Tibetan in August - September and December, 2005. The average concentrations of formaldehyde, acetaldehyde, acetone, and 2-butenal were 4.16 +/- 1.89, 4.25 +/- 3.32, 2.02 +/- 0.86, and 1.93 +/- 1.58 ppbv (n = 42), respectively, in August - September and 1.48 +/- 0.42, 3.91 +/- 0.81, 1.88 +/- 0.69, and 0.69 +/- 0.16 ppbv (n = 12), respectively, in December. Biomass used as fuel for cooking by local residents was considered as the dominant source for 2-butenal. Photooxidation of VOC (especially biogenic emission of isoprene) was one source for formaldehyde and methyl vinyl ketone in August - September. Animal excrement was probably an additional source for formaldehyde and acetone. Back trajectory analysis indicated that long-distance transportation from polluted air might be one important source for formaldehyde, acetone, and acetaldehyde in WLG.