沙尘天气过程对沈阳大气冰核浓度与尺度分布的影响  

Observation on Distributions of Atmospheric Ice Nuclei Concentration and Size under the Influence of Dust Weather

作　　者：周德平[1] 洪也[1] 王扬锋[1] 刘宁微[1] 张云海[1] 李丽光[1] 

机构地区：[1]中国气象局沈阳大气环境研究所,辽宁沈阳110016

出　　处：《中国沙漠》2016年第6期1672-1678,共7页Journal of Desert Research

基　　金：国家自然科学基金项目(41440036;41505120;40975084)

摘　　要：为研究沙尘天气对大气冰核浓度及尺度分布的影响,2010—2012年春季用FA-3型安德森采样器在沈阳地区开展了大气冰核观测,采样后的滤膜在中国气象科学研究院的静力扩散云室中进行统一检测分析。针对2011年5月11—12日一次典型沙尘天气过程,分析了沙尘过程前后大气冰核浓度和尺度分布与变化特征。结果表明：沈阳地区春季大气冰核的本底浓度较高,约为0.8个·L-1（活化温度为-20℃）;沙尘天气出现时可使大气冰核浓度突增10倍以上。约2/3的大气冰核集中在〉4.7μm粒径段;有沙尘影响时,2.11-5.80μm粒径段的大气冰核浓度增加最明显。大气冰核浓度的粒子尺度谱近似服从幂指数n（D）=A·DB分布,其中A和B的数值在沙尘日明显大于非沙尘日。根据观测,建议在沈阳乃至中国北方地区春季有沙尘天气影响时应慎重选择人工影响天气作业方案。To study the impact of dust weather on atmospheric ice nuclei concentration and size distribution factors,observation of atmospheric ice nuclei was conducted in Shenyang with FA-3 Anderson sampler during spring from2010 to 2012.The sampling membrane filters were subsequently analyzed in a static diffusion chamber of Chinese Academy of Meteorological Sciences.Based on the data of atmospheric ice nuclei observed on May11-12 of 2011,we analyzed the atmospheric ice nuclei concentration and size distribution and variation during a typical dust weather process.The results show that the background concentration of atmospheric ice nuclei is high in Shenyang in spring,which is about 0.8 L-1 when the activation temperature is-20 ℃.The concentration of atmospheric ice nuclei may suddenly increase more than 10 times when dust weather occurs.Two-thirds of atmospheric ice nuclei particles concentrate approximately at greater than 4.7μm segment,and the concentration of atmospheric ice nuclei of 2.11-5.80μm diameter segment increases the most obviously during the dust weather process.The particle scale spectrum of the atmospheric ice nuclei approximately obeys exponential distribution,such as nD=ADB,where values of A and B are significantly greater in dust days than non-dust days.According to observed facts,it is recommended that to choose the scheme of the artificial rainfall operations carefully in Shenyang and even in northern China in dust days in spring.

关 键 词：沙尘天气 安德森采样器 滤膜-扩散云室法 大气冰核 尺度谱分布 

分 类 号：P426.3[天文地球—大气科学及气象学]