【摘要】 通过分析2001—2005年河西走廊沙尘活动对兰州PM10浓度的影响并对其进行评估,得出如下结论:兰州的PM10浓度具有双峰值特征,两个峰值分别出现在冬半年的12月和3月,河西沙尘发生次数呈单峰型变化,峰值出现在4月,达到9.8次,对比两者的变化可知,河西沙尘活动的峰值对应春季兰州PM10浓度的次高峰。研究认为冬季特殊边界层条件是造成兰州PM10浓度高峰值的主要原因;春季河西沙尘发生次数与同期兰州PM10浓度呈显著正相关,沙尘暴活动的多发对应兰州PM10浓度次峰值。沙尘指数的定量分析认为,兰州年度(3月,4月)PM10浓度的16.4%(32.0%,47.1%)与河西走廊沙尘活动的影响有关系;兰州年度(3月,4月)PM10质量浓度中的8.8%(13.9%,23.1%)是河西走廊沙尘活动向兰州输送PM10颗粒的结果;河西走廊的沙尘活动能使兰州沙尘影响日PM10浓度增加数倍。河西走廊沙尘活动在不同时间段的影响程度不同。更多还原

【Abstract】 Analysis and assessment on the influence of sand-dust activities in Hexi corridor on the PM10 concentration in Lanzhou city from 2001 to 2005 were conducted in this paper.The following conclusions have been obtained: the annual distribution of PM10 concentration in Lanzhou possessed double peaks,with one peak in December and the other in next March;however,the distribution of the sand-dust activities number in Hexi corridor showed a single peak in April,reaching 9.8 times per month.It is known from correlation analysis that the peak of sand-dust activities in Hexi corridor corresponded to the secondary peak of PM10 concentration during spring in Lanzhou.The winter particular boundary layer condition in Lanzhou was mainly responsible for the first peak of PM10 concentration in December.The quantitative analysis on sand-dust indices indicated that the sand-dust activities in Hexi corridor affect the 16.4% of annual,32.0% of March,and 47.1% of April in PM10 concentration of Lanzhou city,and the 8.8% of annual,13.9% of March,23.1% of April were transported from Hexi corridor.更多还原