中国大气本底条件下不同地区地面臭氧特征

SURFACE OZONE CHARCACTERISTICS AT DIFFERENT AREAS UNDER ATMOSPHERICAL BACKGROUND CONDITIONS IN CHINA

分析了晴天和阴天时瓦里关本底台、临安和龙凤山本底站地面 O3浓度的特点。晴天时 ,临安站地面 O3有明显日变化 ,以春季最大 (42 .9× 1 0 - 9) ,夏季最小 (2 0 .3× 1 0 - 9) ;龙凤山站日变化更规则 ,秋季最大 (约 2 7× 1 0 - 9) ;瓦里关本底台除了夏季有微弱日变化外 ,其它季节没有明显的日变化 ,日较差也很小 ,但夏季地面 O3浓度显著高於冬季 ;夏季晴天瓦里关地面O3浓度要比龙凤山、临安高 2 0× 1 0 - 9以上。阴天时 ,临安和龙凤山站除了日变化不很规则和日较差较小外 ,其它大致与晴天相同。阴天时瓦里关不仅没有日变化 ,而且日较差更小 ,但夏季地面 O3仍然高於冬季。太阳总辐射和 NOx 浓度是控制龙凤山和临安晴天和阴天地面O3浓度的决定性因子 ,它在不同季节和地区发挥着重要作用。夏季青藏高原周围地区气流向高原输送作用 ,是形成夏季瓦里关地面 O3高值以及微弱日变化的主要原因。在美国 MaunaLoa基准站也曾观测到类似的输送影响。O3在低对流层随垂直高度增加的分布特征 ,决定了东西部测点地面

The characteristics of surface O 3 on clesr day,cloudy and rain dya at Waliguan observatory, Lin'an regional station and Longfengshan regional station were analyzed.There were obvious daily variation on clear dya at Lin'an. The maximum (42.9 ppb) and minimum (20.3 ppb) of daily varation presented in autumn and summer,respectively. The daily variation was more regular at Lonfengshan than at Lin'an.The maxmum (about 27 ppb) presented in autumn at Lonfengshan. There was not obvious daily variation and also daily range was smaller in other seasons except summer (there were weak daily variation) at Wailiguan. But the surface O 3 concentration in summer was higher than winter. The surface O 3 concentration on clear day of summer at Waliguan was over 20 ppb higher than it at Longfengshan and Linan.Except daily variation was not very regular and daily range was smaller on overcast at Linan and Longfengshan, the others ere same to on clear day. There was non-daily variation. also daily range is smallest on overcast at Waliguan. But the surface O 3 concentration in summer was still higher than winter. Both golbal radiation adn NO x concentration were main factors to control surface O 3 concentration on clear day and overcast at Longfengshan and Lin'an. They broutht into important play in different seasons and areas. The main reason for higher air pollutant concentration in summer at Waliguan was that air flow of higher air pollutant concentration of area around Qinghai-Tibetan plateau transported into this area. The similar effect of transportation was obtained at Mauna Loa observatory. The distribution characteristics of surface O 3 concentration increasing with vertical high in troposphere decided the difference of surface O 3 between east and west in China.