冷锋天气大气边界层内臭氧及 氮氧化物的观测研究

利用北京325 m气象塔作为高空平台，于1997年10月观测到一次冷锋过程大气边界层内O3及NOx体积分数的变化，研究了O3及NOx体积分数与气象要素之间的关系，着重讨论了冷锋过境前后O3及NOx的体积分数变化及其与输送过程的关系。研究表明:北京大气边界层中下层存在明显的O3体积分数垂直梯度，O3的垂直输送与风速及温度梯度密切相关。冷锋过程有利于高层O3向低层输送，使O3体积分数垂直梯度明显减小，并使NOx体积分数显著降低。

Measusements of O3 and NOx in Urban Atmospheric Boundary Layer of Beijing during a Passage of Cold Front

Based on the Beijing 325 m meteorological tower, O 3 and NO x concentrations in urban atmospheric boundary layer were measured from October 22, 1997 to October 31, 1997 during a cold front passage The relations between O 3, NO x and meteorological parameters were studied, and the variations of O 3 and NO x during the passage of cold front were discussed Our results indicate that there is a downward O 3 flux in urban atmospheric boundary layer of Beijing, the vertical transportation of O 3 has a close relation with wind speed and the vertical temperature gradient During the passage of cold front, the vertical gradient of O 3 and NO x concentrations decreased remarkably