中国地区对流层臭氧变化和分布的数值研究

A NUMERICAL STUDY OF THE VARIATIONS AND DISTRIBUTIONS OF TROPOSPHERIC OZONE AND ITS PRECURSORS OVER CHINA

中文关键词:  中尺度模式(MM5)  空气质量模式  对流层臭氧

英文关键词:MM5  Air quality model  Tropospheric ozone

中文摘要:

      利用三维中尺度非静力模式MM5和化学模式,对1994年8月16～18日,1995年1月7～9日冬夏两个不同时期中国大陆大气对流层臭氧及其前体物质的分布进行了数值模拟。同时深入地分析了青藏高原地区夏季对流层臭氧的分布。模拟结果地面臭氧和NO_x的分布与观测结果基本一致,人类活动和光化过程是决定地面臭氧和NO_x的主要因子。对流层臭氧浓度的分布与气流的辐合辐散存在较好的对应关系,辐合区臭氧浓度较高,辐散区臭氧浓度较低。夏季,青藏高原中低空存在很强的辐合气流,使周边臭氧向高原辐合;而高原高空,受南亚高压控制存在很强的反气旋环流,臭氧由高原向周边辐散。冬季,受西风气流控制,臭氧分布表征大尺度特征。西风急流区臭氧浓度偏低,而急流两侧臭氧浓度偏高。

英文摘要:

      The mechanism of the distributions of tropospherico zone and its precursors over China has been simulated by means of three-dimensional MM5 and chemical model in summer and winter time, 16～18 August 1994 and 7～9 January 1995, and the distribution of ozone over Tibetan Plateau in summer time is deeply discussed. The simulated results indicated that the distributions of surface ozone and NO_x have a good agreement with measured results, and human activities and photo chemical reactions are the main factors controlling the surface ozone and NO_x concentration. In addition, higher ozone concentrations are coincided with the air convergence, and the lower are related to the air divergence. In summer, over Tibetan Plateau the strong flow convergence results in higher ozone concent rations in the lower troposphere; and the strong flow divergence results in lower ozone concent rations in the upper troposphere. In winter time ozone concentrations show large scale characteristics controlled by western flow, the ozone concent rations in jet area are lower than the other areas.