利用MECCA大气化学模式,考虑卤素类(Br,Cl和I)物质的化学过程,对海洋大气边界层内臭氧和NOx的日变化进行了模拟,并与实测数据进行了对比.结果表明,当考虑这些影响后,ψ(O3)略有降低并且产生峰值的时间提前,这主要是由于Br,BrO,Cl和ClO等物质浓度在日出后很快达到峰值所致,基于同样的原因,NO2变化也有类似的特点.在清洁环境下,海洋大气边界层内臭氧的消耗主要由HOx,O(^1D)+H2O和卤素控制,白天以卤素对臭氧的消耗为主.此外还模拟了不同ψ(NOx)下臭氧的日变化,得出在高ψ(NOx)情况下,边界层内臭氧可由净损耗变为净增长.
The diurnal variation of ozone and NOx in marine atmospheric boundary layer was studied by atmospheric chemical model MECCA, with the modeling results compared with the observed data. Halogen (Br, Cl and I) chemical processes were considered in this model. When the influence of halogen chemical processes was included in the model, a decrease of ozone concentrations and time advance of the peak concentration of ozone are revealed. The main reason is that the reactive halogen radicals such as Br, BrO, Cl and ClO show peaks after sunrise. As the same reason, the NO2 has the same change tendency with ozone. In clean environment, ozone destruction rate in marine atmospheric boundary layer was mainly controlled by HOx, O(^1D) + H2O and halogen species, and during the daytime, the ozone destruction was mainly derived from reactive halogen species. The impact of variation of initial NOx concentration on ozone concentration was also studied. In high NOx situation, there is a net production of ozone in marine atmospheric boundary layer.