摘要
Ozone chemistry processes are analyzed during a cumulus cloud process with the model (1CCCM)described in Part Ⅰ.The simulation results show that entire cumulus cloud process can be well described with the development of vertical velocities and liquid water content which are the two most outstanding features of cumulus clouds.Ozone chemistry is strongly influenced by cumulus clouds.NO_x can be transported upwards above 4 km in the first 20 minutes of the convection event and form a relative higher concentration area which enhances the production of ozone.Two areas ap- pear during the convection event:area of net ozone production and area of net ozone depletion.The area of ozone depletion coincides with the area of liquid water within cloud.Results show that the aqueous phase(cloud water and rainwater)can alter gas ozone level through two ways:one is scav- enging free radicals(HO_2)from the gas phase and thereby inhibiting the reactions of transformation to NO_2 from NO,which results in reduction of the gas source of ozone;the other is aqueous phase chemical reactions which consume ozone in the aqueous phase.Calculations reveal that the reaction O_3 +OH→HO_2 is the main pathway of ozone depletion in gas phase during the process of cumulus clouds.
Ozone chemistry processes are analyzed during a cumulus cloud process with the model (1CCCM)described in Part Ⅰ.The simulation results show that entire cumulus cloud process can be well described with the development of vertical velocities and liquid water content which are the two most outstanding features of cumulus clouds.Ozone chemistry is strongly influenced by cumulus clouds.NO_x can be transported upwards above 4 km in the first 20 minutes of the convection event and form a relative higher concentration area which enhances the production of ozone.Two areas ap- pear during the convection event:area of net ozone production and area of net ozone depletion.The area of ozone depletion coincides with the area of liquid water within cloud.Results show that the aqueous phase(cloud water and rainwater)can alter gas ozone level through two ways:one is scav- enging free radicals(HO_2)from the gas phase and thereby inhibiting the reactions of transformation to NO_2 from NO,which results in reduction of the gas source of ozone;the other is aqueous phase chemical reactions which consume ozone in the aqueous phase.Calculations reveal that the reaction O_3 +OH→HO_2 is the main pathway of ozone depletion in gas phase during the process of cumulus clouds.
基金
This work was supported by the National Natural Science Foundation of China.
