四川盆地最大混合层厚度与大气污染物浓度的关系  

The Relationship between the Maximum Mixing Depth and the Concentration of Atmospheric Pollutants in Sichuan Basin

作　　者：张峥子 冯鑫媛 危诗敏 ZHANG Zhengzi;FENG Xinyuan;WEI Shimin(College of Atmospheric Sciences,Chengdu University of Information Technology,Plateau Atmosphere and Environment Key Laboratory of Sichuan Province,Chengdu 610225,China;Yixian County Meteorological Bureau of Anhui Province,Huangshan 245021,China)

机构地区：[1]成都信息工程大学大气科学学院/高原大气与环境四川省重点实验室,成都610225 [2]安徽省黄山市黟县气象局,黄山245021

出　　处：《高原山地气象研究》2020年第4期90-96,共7页Plateau and Mountain Meteorology Research

基　　金：国家自然科学基金项目(41775147);国家自然科学基金重大研究计划重点支持项目(91644226);四川省科技厅科研项目(2019YJ0362)

摘　　要：基于2015~2018年四川盆地温江站、宜宾站、达川站和沙坪坝站的探空和地面观测资料以及同期AQI、6种主要污染物(SO_(2)、NO_(2)、CO、O_(3)、PM_(2.5)、PM_(10))质量浓度资料,使用逐步逼近法计算得到了四川盆地成都、宜宾、达州、重庆四城市的每日最大混合层厚度(Maximum mixing depth,MMD),并对其时间变化特征及其与各种污染物浓度之间的关系进行了分析。结果表明,四川盆地年平均MMD约1200m。季节变化明显,春夏高、秋冬低。9月至次年1月MMD相对较小。相关分析显示,剔除降水影响后,MMD与AQI、PM_(2.5)、PM_(10)、SO_(2)、NO_(2)、CO浓度均呈负相关,而与O_(3)浓度显著正相关。在污染最为严重的冬季,MMD明显低于春夏季节。MMD越小、颗粒物浓度越高。低MMD大大压缩了近地面污染物的扩散空间,污染物在有限的空间内不断累积、浓度增大。The stepwise approximation method was applied to analyze sounding data,ground data,AQI data and the six main pollutants(SO_(2),NO_(2),CO,O_(3),PM_(2.5),PM_(10))mass concentrations data collected at Wenjiang Station,Yibin Station,Dachuan Station and Shapingba Station in Sichuan Basin during 2015-2018,and calculate daily maximum mixing depth(MMD).At the same time,the time variation characteristics of MMD and the relationship between the MMD and the concentration of various pollutants were analyzed.The results show that the annual average MMD of Sichuan Basin is about 1200 m.The seasonal variation of MMD is obvious,larger in spring and summer but smaller in autumn and winter(relatively small from September to January of the following year).Correlation analysis showed that after excluding the effect of precipitation,MMD was negatively correlated with AQI,as well as the mass concentration of PM_(2.5),PM_(10),SO_(2),NO_(2),CO,but positively correlated with the mass concentration of O_(3).Pollution is the most serious in winter,and the MMD in winter is significantly smaller than that in spring and summer.The smaller the MMD,the higher the concentration of particulate matter.Small MMD greatly compresses the diffusion space of near-surface pollutants,which accumulate and increase in concentration in a limited space.

关 键 词：最大混合层厚度 逐步逼近法 四川盆地 空气污染 

分 类 号：P427.2[天文地球—大气科学及气象学]