乌鲁木齐气象要素对大气气溶胶光学特性的影响

Effects of Meteorological Factors on Optical Properties of Aerosol in Urumqi

利用2002年4月-2003年3月CE 318太阳光度计和同期气象观测资料，分析不同气象条件下，乌鲁木齐气溶胶光学厚度的变化。结果表明：在冬季高湿的条件下，各时次相对湿度和AOD的相关系数较高，为0．335。春夏季比较干燥时，相对湿度的影响不大；风速和AOD的变化趋势总体呈现负相关关系，即风速越大，AOD则越小，在发生东南大风或山谷风时，这种趋势更为明显；全年中偏北风和偏南风对乌鲁木齐气溶胶光学厚度的贡献较大。

The data measured with sun photometer CE318 are used to culculate the aerosol optical depth （AOD） in Urumqi during the period from April 2002 to March 2003. The analyzed results reveal that the correlation coefficient between the relativity humidity and AOD under high humidity in winter is high （0. 335）, but low in dry seasons, such as in spring and summer, which reveal that the relative humidity in winter is an important factor affecting AOD. In general, there is a negative correlation between wind speed and AOD, their correlation coefficient is - 0. 135, which means the higher the wind speed is, the lower the ACID will be. Such trend is more significant when southeastern and mountain-valley breeze occur. The negative correlation between wind speed and AOD can be changed as positive one, for example, dust weathers occur sometimes in fine days in spring, the higher the wind speed is, the more the aerosol will be transported to Urumqi. Under such situation, AOD and wind speed are synchronously increased. Moreover, the contribution of north wind and south wind to AOD is higher than that of other wind directions.