上海地区SO2的观测研究

1986年6月中旬到7月中旬,采用飞机与地面定点测量,对上海地区SO_2空间及地面的分布、变化进行了观测研究,得出了如下结果:1.在降水较频繁的观测期间,上海近郊地面(龙华机场)SO_2的平均日变化呈一峰一谷分布,峰值在08时;约34ppb,谷值在02时,约10ppb,全天平均为18ppb。但在连续的晴天状况下,SO_2日变化呈二峰二谷分布,2.SO_2空间分布有两大特征。一是不稳定大气层结(晴天)下的向上递减型,1500m以下,城市比郊区大10ppb左右,1500m以上,市区、郊区的浓度趋于一致,相差只1—2ppb。二是层状云中SO_2浓度垂直分布先向上递增,约在1500m高度上达极值,然后又向上递减。3.资料分析发现,云中SO_2浓度越高的地方,云水的酸度也越大。4.冷锋,准静止锋天气过程,每次都伴随SO_2日均浓度分布曲线上的一个峰值。

The Measuremental study of SO2 in Shanghai area

Measurements for spatial and temporal distributions of SO2 were made both at the surface and in the space of Shanghai area by using airplane and Fluorescent SO 2 Analyser 8850 from June 21 to July 13 , 1986. Upon the datum analysis the diurnal average variation of SO 2 of the concentrations distributions at the surface and in the space in the area is given in the paper. The daily average concentration of SO2 in Longhua airport is 18ppb or so. In sunny days the diurnal variation of SO 2 is a curve with two peakvalleys. The spatial distribution of SO 2 in Shanghai area is divided into two types. One is that SO 2 decreases with height in unstable atmospheric condition. The other is that SO 2 increases with height at first (below 1500m) and decreases with height later (above 1500m), a maximum concentration usually appears at 1500 m or so. In straturs somewhere the higher the SO 2 concentration is, the stronger the acidity of cloud-water ap -pears. It also shows that each weather process of cold front and quasi- static front corresponds to one peak value of the curve of diurnal average concentration of SO2.