中国西部大气清洁地区黑碳气溶胶的观测研究

OBSERVATIONAL STUDY OF BLACK CARBON IN CLEAN AIR AREA OF WESTERN CHINA

黑碳气溶胶是大气气溶胶中的重要成分，对可见光和红外光都具有强烈吸收作用，对气溶胶的局地及全球的气候效应有重要的贡献．本文给出了１９９４年７月到１９９５年底在瓦里关本底台进行的黑碳气溶胶观测结果，结合气象观测资料以及在我国东部地区的部分观测结果对该地区大气中的黑碳气溶胶浓度及其变化特点进行了讨论分析．瓦里关山地区的大气黑碳气溶胶月平均浓度为１３０～３００ｎｇ／ｍ３，大大低于我国东部地区；该地区大气中黑碳气溶胶浓度的变化明显地与来自工业及人口集中地区的污染气团的影响有关，不同风向时的黑碳气溶胶浓度水平有明显的差异；由最大出现频数统计分析得出该地区大气黑碳气溶胶的本底浓度范围为５０～１２０ｎｇ／ｍ３；冬季该地区大气黑碳气溶胶的平均浓度和本底浓度都较低，而春季较高．

Black carbon which has a strong absorption in the visible and infrared range is an important component of aerosols, therefore it contributes significantly to the regional and global climatic effects on aerosols. The observational results of black carbon from July 1994 to December 1995 at Mt. Waliguan Observatory are given. The characteristics of black carbon concentration variation are discussed combined with the meteorological observational data, and then the results were compared with the observational data of black carbon in eastern China.The mean monthly black carbon concentration at Mt. Waliguan varies in the range of 130-300 ng/m 3, much lower than that of the eastern China. The variation of black carbon concentration shows an obvious episode pollution transportation under the influence of industrial and dense populated areas, and it varies obviously with the ground wind direction. The background concentrations of black carbon at Mt. Waliguan derived from the mode values of the most frequency statistics, are in the range of 50-120 ng/m 3. Both the average concentrations and background concentration are lower in winter and higher in spring.