000030026 001__ 30026
000030026 041__ $$aEnglish
000030026 100__ $$aWang, Q.
000030026 245__ $$aBlack Carbon Aerosol Characterization in a Remote Area of Qinghai–Tibetan Plateau, Western China
000030026 260__ $$c2014
000030026 269__ $$c5/1/
000030026 300__ $$a151-158
000030026 500__ $$aOpen access article
000030026 520__ $$aThe concentrations, size distributions, and mixing states of refractory black carbon (rBC) aerosols were measured with a ground-based Single Particle Soot Photometer (SP2), and aerosol absorption was measured with an Aethalometer at Qinghai Lake (QHL), a rural area in the Northeastern Tibetan Plateau of China in October 2011. The area was not pristine, with an average rBC mass concentration of 0.36 μg STP-m− 3 during the two-week campaign period. The rBC concentration peaked at night and reached the minimal in the afternoon. This diurnal cycle of concentration is negatively correlated with the mixed layer depth and ventilation. When air masses from the west of QHL were sampled in late afternoon to early evening, the average rBC concentration of 0.21 μg STP-m− 3 was observed, representing the rBC level in a larger Tibetan Plateau region because of the highest mixed layer depth. A lognormal primary mode with mass median diameter (MMD) of ~ 175 nm, and a small secondary lognormal mode with MMD of 470–500 nm of rBC were observed. Relative reduction in the secondary mode during a snow event supports recent work that suggested size dependent removal of rBC by precipitation. About 50% of the observed rBC cores were identified as thickly coated by non-BC material. A comparison of the Aethalometer and SP2 measurements suggests that non-BC species significantly affect the Aethalometer measurements in this region. A scaling factor for the Aethalometer data at a wavelength of 880 nm is therefore calculated based on the measurements, which may be used to correct other Aethalometer datasets collected in this region for a more accurate estimate of the rBC loading. The results present here significantly improve our understanding of the characteristics of rBC aerosol in the less studied Tibetan Plateau region and further highlight the size dependent removal of BC via precipitation.
000030026 653__ $$aRefractory Black Carbon
000030026 653__ $$aSize Distribution
000030026 653__ $$aMixing State
000030026 653__ $$aTibetan Plateau
000030026 700__ $$aSchwarz, J. P.
000030026 700__ $$aCao, J.
000030026 700__ $$aGao, R.
000030026 700__ $$aFahey, D. W.
000030026 700__ $$aHu, T.
000030026 700__ $$aHuang, R. J.
000030026 700__ $$aHan, Y.
000030026 700__ $$aShen, Z.
000030026 773__ $$pScience of The Total Environment
000030026 773__ $$v479–480 (0)
000030026 773__ $$ahttp://dx.doi.org/10.1016/j.scitotenv.2014.01.098
000030026 8564_ $$uhttp://www.sciencedirect.com/science/article/pii/S0048969714001260$$yExternal link (Open access)
000030026 980__ $$aARTICLE