北京市大气静稳型重污染的印痕分析

2004年10月1-10日,北京出现了一次典型的大气静稳型重污染过程.利用印痕(footprint)分析方法,结合主要污染物 PM10 的逐时浓度监测数据,对这次静稳型重污染过程及其影响源地进行分析.结果表明:1) 重污染过程中PM10浓度的日变化特征有明显改变,下午和晚上出现高浓度;2) 北京地区PM10浓度的水平分布总体呈"南高北低"形势;3) 重污染发展阶段伴随着印痕分布区域不断朝偏西南方向延伸的过程,延伸区域达100～200 Km ,反映西南方向源区对这次重污染的明显贡献.

Footprint Analysis for a Stagnant Air Pollution Episode in Beijing

A typical stagnant air pollution episode happened during October 1 to 10, 2004 in Beijing. Using the method of footprint analysis and the monitoring data for major pollutant (PM10) in this period, detailed process and the source-area of potential influence in this episode were analyzed. Results illustrate that: 1) the diurnal variation of PM10 concentration differs significantly from usual case, and high concentration appeares in the afternoons and evenings, 2) the horizontal distribution of PM10 concentration has a pattern as "the higher in the south and the lower in the north", and 3) the development of the episode is accompanied with obviously extending of the footprint 100- 200?km to the southwest of Beijing, suggesting that source emission from the southwest may contribute significantly to this heavy pollution episode.