Optimization of Initial Field of PM2.5 Transport Model
SHEN Youli
ZHANG Chunhua
LIN Mingyu
LI Ning
ZHANG Shaofeng
Abstract：The adjoint assimilation scheme was applied to a PM2.5 adjoint assimilation model construction,based on the transport characteristics of PM2.5.The model was applied to the Chinese mainland,and the PM2.5 initial field was optimized.The pollution situation of Chinese mainland features two ideal PM2.5 initial field distributions involving parabolic surface with down convex in North China and East China and upward convex in western China.The forementioned distributions were optimized by the adjoint model.Experiment results suggest that the cost functions,mean absolute errors of observations,and mean absolute errors of optimization results and prescribed distributions were decreased drastically after assimilation.The optimization results were also rather more approximate to the prescribed distributions,indicating that PM2.5 initial field could be efficiently estimated.Meanwhile,the optimization result might be poorly favorable because of lack of effective observations,compared with optimization process of the two forementioned prescribed distributions.Two sensitive experiments involving increases and decreases effective observations were implemented,and optimization efficient was more obvious if ratio of effective observations was increased.This study prepares for the future accurate PM2.5 simulation.
Keywords：adjoint assimilationinitial fieldeffective observation
Publication Date：2017-01-01
Pages：6( 63-68 )