Influence of A Sand-dust Weather Process on Aerosol Mass Concentration and Number Concentration in Tianjin,China

Based on aerosol mass concentration and number concentration data and meteorological data at different heights and backward trajectory analysis,the influence of a sand-dust weather process from April 30 to May 1 in 2011 on aerosol concentration in Tianjin were analyzed.The results indicated as follows.In the mist process before sand-dust weather,PM1 accounted for about 96% of aerosol mass concentration and 99.9% of aerosol number concentration;PM1-2.5,PM2.5-10 and PM10-100 accounted for about 6.5%,2.5% and 0.1% respectively of total aerosol number concentration in the first floating dust process,11.3%,2.6% and 0.01% respectively in the second floating dust process;the mass concentration and number concentration of fine aerosol under two floating dust processes were obviously different because of the increase of the ratio of fine aerosol,which resulted in change of aerosol property.