塔克拉玛干沙漠腹地沙尘气溶胶对低层大气的加热效应  

The heating effect of dust aerosol on air temperature in the surface layer in the hinterland of Taklimakan Desert

作　　者：陈霞[1,2] 魏文寿[3] 顾光芹[1,2] 安月改[1,2] 

机构地区：[1]河北省气象与生态环境重点实验室,石家庄050021 [2]河北省气候中心,石家庄050021 [3]中国气象局乌鲁木齐沙漠气象研究所,乌鲁木齐830002

出　　处：《气象学报》2012年第6期1235-1246,共12页Acta Meteorologica Sinica

基　　金：河北省气象局科研开发重点项目(11ky07);公益性行业科研专项(GYHY200706008);中国科学院研究生科技创新类项目

摘　　要：利用塔克拉玛干沙漠腹地塔中气象站2006年8月1日—2007年7月31日近地层80m铁塔逐时温度、辐射和5minPM10浓度、黑碳(BC)质量浓度、散射系数等数据,结合地面常规气象数据筛选出四季沙尘过程,剔除云的影响,以每次沙尘过程的晴空为大气背景值,分析沙尘气溶胶对低层大气的加热效应。结果表明,沙漠腹地沙尘过程对低层大气日平均温度有显著的增温效应,扬沙在冬、春季最剧烈,日平均温度分别高出晴空3.4和3.8℃,沙尘暴其次,浮尘最小。沙尘过程显著地增大了大气逆辐射量,沙尘暴日平均为晴空的1.24倍,扬沙为晴空的1.21倍。沙尘影响低层大气温度梯度分布,显著缩短了大气的逆温时间,减弱了逆温强度。沙尘过程对低层大气增温的原因,春季是大粒子浓度的显著增大,冬季是吸收性粒子的增多,而夏、秋季则为小粒子浓度的增大和散射系数的增大。低层大气温度梯度在扬沙天气随PM10的增加而减小,主要由低层10m以下大气温度变化引起;浮尘天气主要与小粒子浓度关系密切,其影响高度最大,春、夏季可以达全层80m,秋、冬季也可超过32m;沙尘暴一致性较差,除秋季外,均由2m以内温度变化所致。The data was recorded including air temperature, radiation, PM10, concentration of black carbon （BC） and scattering coefficient of sand dust in the hinterland of Taklimakan Desert from 2006 Aug. 1 to 2007 Jul. 31. Combination with the conventional meteorological data, weather types were divided into four categories, as blowing dust, dust storm, floating dust and clear sky. Cloudy days were removed and the temperature of clear sky was set as an atmospheric background value in each dust progress to analyse heating effect of dust on air in the surface layer. The results show that daily average temperature in the blo- wing dust was higher than the clear sky by 3.4℃ and 3.8℃ in winter and spring respectively. The dust also increased atmos- pheric inverse radiation which was as 1.24 times as the clear sky. The dust influenced the distribution of the temperature gradi- ent of air in the surface layer, it shortened the time and weakened the intensity of temperature inversion. The large particles as PM10 increasing significantly in spring, absorptive particles rising strongly in winter, and small particles augmenting greatly in summer and autumn all lead to the heating effect though in a different way. Changes of temperature gradient in blowing dust were decreasing with the increasing PM10, which was caused mainly by the air temperature variation below 10 m height. In floating dust, it was significantly correlative with small particles, and its influencing heights were much higher than the other weather types, which exceeded 32 m.

关 键 词：沙尘气溶胶 加热效应 PM10浓度 沙尘气溶胶散射系数 黑碳质量浓度 塔克拉玛干沙漠 

分 类 号：P404[天文地球—大气科学及气象学]