兰州大气污染物浓度与局地气候环境因子的关系

A study of the interaction between concentration of pollutants and the climatic and environmental factors of Lanzhou

利用 2 0 0 0年 1 2月 1 0～ 1 7日在兰州市城区的大气边界层观测资料以及同期的污染物浓度监测资料、自动气象站观测资料和常规气象站辐射观测资料等 ,通过山谷内市区污染物浓度变化与山谷外对照点的比较 ,研究了兰州市城区污染物浓度的变化特征 ;分析了对应时期兰州市山谷气候环境因子和特征参数的变化 .结果发现 ,大气中污染物对太阳辐射的吸收增温与白天大气逆温层之间有明显的正反馈机制 ,而且这种反馈机制在白天大气逆温层的形成和发展过程中起主导作用 ;讨论了兰州市山谷大气污染物浓度与大气逆温、水平风速、Froude数和边界层稳定度参数之间的简单关系 .

Using the data on wind speed, wind direction, temperature and humidity of the atmospheric boundary layer observed with tethered balloon profiler in Lanzhou city as well as the concentration of pollutants observed by detection stations, temperature of surface layer observed with a automatic meteorological station (AMS) and surface global radiation obtained by formal meteorology station, the relationships between the intensity of inversion and concentration of pollutants in atmospheric boundary layer are studied, with a comparison of the concentration of pollutants over Lanzhou valley with that over the outside of the valley. The characteristics of change of climatic and environmental factors as well as characteristic parameters over Lanzhou valley during uhe same period are analyzed. There exists a clear and positive feedback mechanism between the intensity of atmospheric inversion and pollutants.Finally, the simple relationship between the concentration of pollutants and the intensity of atmospheric inversion, horizontal wind speed, Froude number and the stability parameter of the boundary layer is discussed.