上甸子区域本底站大气痕量活性气体的变化规律

THE VARIATION CHARACTERISTICS OF TRACE REACTIVE GASES AT SHANGDIANZI REGIONAL BACKGROUND MONITORING STATION

利用TE公司C系列气体监测仪,于2005年1月1日—12月31日,在北京上甸子区域大气本底站连续观测SO2,CO,NO-NO2-NOx和O3的浓度.分析了晴天、雨天、霾天和沙尘天气条件下,不同气体的变化特征及影响因素.结果表明:(1)痕量活性气体在不同天气条件下具有不同的浓度及日变化特征,晴天和雨天日变化最小,而霾天日变化最大;(2)风向和风速是影响上甸子气体浓度变化的重要因素,同时,夏季降水对SO2和NOx的去除作用较为明显;(3)上甸子O3白天最大值与夜间最小值的比值低于4,远低于城区,不利于光化学污染的形成.

TE C series air analyzers were used to continuously monitor SO2, CO, NO-NO2-NO, and surface ozone at Shangdianzi regional background monitoring station in Beijing from Jan. 1 to Dee. 31, 2005. The variation characteristics of these trace reactive gases and the factors which influenced them were analyzed under different weather conditions such as in sunny days, rainy days, hazy days and sand-dusty days. The main results included： （1） Concentrations and diurnal variations of them were quite different. The diurnal variations were most obvious in hazy days, and not obvious in sunny and rainy days. （2） The main factors which influenced the concentrations and variations were wind direction and wind speed. It was obvious in summer that SO2 and NOx were wiped off by rain. （3） The ratio of maximum value during day time and minimum value during night time of surface ozone was less than 4, far lower than that in the urban area.