云对云中大气臭氧影响因子的分析

Numerical Study of the Impact of Clouds on Atmospheric Ozone

应用一个较详细的气相光化学和液相化学耦合的箱体模式， 研究了云层对云中大气臭氧的影响过程。这一过程可分解为三个因子来考虑： 因子Ａ （云的辐射效应）， 由于云的存在改变太阳光辐射通量， 使得对流层光化学反应减弱或增强， 从而降低或增加臭氧浓度； 因子Ｂ（云的吸收效应）， 云层中液态水对大气臭氧及其前体物 （ＮＯｘ、ＮＭＨＣ、自由基等） 的直接吸收作用； 因子Ｃ（云的液相化学效应）， 吸收进入云中的物质发生液相化学反应从而改变大气臭氧浓度。数值研究结果表明： 上述三因子对云中臭氧浓度影响的程度差别很大， 并且与云层的物理结构有密切关系。

A cloud-chemistry box model is developed to study ozone chemistry processes and the impact of clouds on the distribution of atmospheric ozone in upper part and lower part of the cloud layer The cloud-chemistry model composes of three parts: gas phase photochemistry, aqueous phase chemistry and scavenging of soluble gases The impact of clouds on atmospheric ozone can be divided into three factors to be considered Factor A (radiant impact of clouds): Because of cloud changing the radiant flux, the photochemical reactions in troposphere are weaken or strengthen, and then the concentration of ozone is decreased or increased Factor B (impact of cloud absorption): The liquid water in the cloud can directly absorb ozone and its precursors (NO x , NMHC, radical, etc ) And Factor C (impact of aqueous phase chemistry in clouds): The soluble gases, which are absorbed into aqueous phase, will take place chemical reaction and then decrease ozone in the gas phase indirectly Numerical studies show that the three factors of clouds have distinct impacts on atmospheric ozone in the different level of the clouds, and the physical structures of clouds strongly influence the importance of the three factors The main causes of the impact of cloud absorption and aqueous phase chemistry in clouds on atmospheric ozone are finally discussed