塔克拉玛干沙漠腹地冬季大气边界层O_3廓线分析

Profiles of Atmosphere Boundary Layer Ozone in Winter over Hinterland of Taklimakan Desert

为了揭示塔克拉玛干沙漠腹地冬季大气边界层O3的浓度变化特征,利用系留气艇于2008年1月18—25日在塔中地区进行了大气边界层O3观测试验,结合相关资料,初步分析了塔中地区冬季边界层O3浓度垂直分布特征及其与温度、湿度的关系。其结果是:①塔中地区臭氧浓度集中分布在10～50ppb之间,其中试验期间观测到O3最大浓度值56.1ppb,最小浓度为2.6ppb,臭氧的最大浓度基本都在40ppb左右,日平均浓度为34.4ppb。②大气边界层O3的浓度廓线可分为峰值型、均匀型、增长型3种,其中均匀型所占比重最大。③大气边界层O3浓度与温度、湿度密切相关,逆温及空气中水汽的增加会导致臭氧浓度降低。④大气边界层O3有明显的日变化,越贴近地面日变化越明显,其变化特征与太阳辐射有着密切关系。臭氧浓度夜晚较低,日出后开始增加,午后达到一天中的最大值;随着日落,臭氧浓度开始减小,在清晨达到最小值;臭氧浓度日最大值出现在17:00,最小值出现在08:00。

In order to disclose the variation characteristics of ozone concentration in the atmosphere boundary layer over desert hinterland in winter, an observation experiment has been carried out at Tazhong Atmosphere and Environment Observation and Experiment Station in Taklimakan Desert by the use of tethered balloon during January 18--25, 2008. The vertical distribution of O3 concentration and its correlation with temperature and humidity are analyzed based on the observation experiment data and related data. The results show that： （1） The concentration of 03 mainly ranges in 10-50 ppb, and the maximum is 56.1 ppb and the minimum is 2.6 ppb. The daily average O3 concentration is 34.4 ppb. （2） The O3 profile can be divided into three types： peak, uniform, and growth, while the type of uniform has the largest proportion. （3） The impact of temperature and moisture in atmosphere boundary layer on concentrations of ozone is significant. The temperature inversion and water vapor increase in atmosphere boundary layer lead to the reduction of concentrations of ozone. （4） O3 concentration has an obvious daily change in Tazhong. It is lower at night, then it begins to increase after sunrise and it comes into the maximum at noon. The maximum ozone concentration appears in 17：00 BST, the minimum appears in the 08：00 BST.