青海德令哈大气气溶胶光学特征及可降水量分析

Analysis of Optical Characteristics of Atmospheric Aerosol and Precipitable Water Vapor in Delingha,Qinghai

大气中气溶胶光学厚度和可降水量情况为天文选址提供必不可少的评价依据,为天文观测提供重要参考。利用DTF型太阳辐射计对青海德令哈进行观测,获得2013年9月至2015年1月晴天无云条件下的观测结果,进而得到该地区观测期间气溶胶光学厚度、Angstrm指数和大气可降水量的日变化与季节变化特征。该地区的气溶胶光学厚度和可降水量日变化类型较多,可分为六种,有一定的季节性特征.不同季节中,秋季气溶胶光学厚度最小,其他季节相当,而可降水量在夏季最大,明显高于其他季节.Angstrm指数春季最小,夏季和秋季次之,冬季最大。总体来说青海德令哈的气溶胶光学厚度和可降水量都较小,大气较干净稳定,适合天文观测.

The atmospheric aerosol optical thickness and the precipitable water vapor provide the essential evaluation basis for the astronomical site selection, and important reference for astronomical observation. DTF type sun-photometer is used to observe the diurnal, seasonal variation of the aerosol optical thickness,AngstrSm index and the precipitable water vapor in clear and cloudless weather from September 2013 to January 2015 in Delingha, Qinghai Province, China. The results show that the region of the aerosol optical thickness andthe precipitable water vapor type can be divided into six kinds and has some seasonal characteristics. During different seasons, the aerosol optical thickness is the minimum in autumn, nearly in other seasons, and the precipitable water vapor is the largest in summer, obviously more than other seasons. The AngstrSm index is the minimum in spring, the largest in winter and nearly in summer and autumn. Overall the small aerosol optical thickness, the low amounts of precipitable water vapor, and the clean air make Delingha an appropriate site for astronomical observation.