Improvement Of Temporal And Spatial Allocation In SMOKE

Air quality simulation platforms,including SMOKE/WRF/CMAQ and SMOKE/WRF/CAMx,have been widely applied in air quality management study,pollution formation study and pollution forecasting in many countries and regions..However,as revealed by previous studies,one limitation lied in SMOKE is the spatio-temporal allocation of annual emissions using preset uniform monthly-daily-hourly temporal profiles and time-invariant spatial profiles,which is not appropriate for sources with complex spatio-temporal distributions.In order to improve SMOKE model associated with temporal and spatial allocation,an new temporal and spatial allocation method that combined a dynamic allocation method based on the responses of emission to meteorological fields with a preset method.The new method was applied in spatio-temporally allocation of dust source and livestock source in the Pearl River Delta region.In addition,a source-specific vertical allocation module was developed to allocate elevated area emissions at vertical layers.Contents of this study are as follow.Firstly,mathematical models associated with precipitations and dust emission rate were established based on the literature research.Next,online spatio-temporal reallocation models for dust source embedded in SMOKE was developed.Similarly,online spatio-temporal reallocation modules for livestock was also developed based on the existing mathematical model of meteorological fields and the ammonia fugitive emission,such as RC formula and ZH formula.Air quality model was used to identify the influence of different online spatio-temporal reallocation modules on PM2.5 simulations in the Pearl River Delta region.It was found that these online spatio-temporal reallocation modules generally enhanced the PM2.5 simulation in CMAQ.Finally,following the method of spatial allocation in SMOKE,a vertical allocation module based on source-specific vertical profiles was developed and incorporated into SMOKE.Marine and residential combustion were vertically allocated by using this method.However,CMAQ modelling did not saw expected improvement,which might due to the uncertainty of the preset vertical allocation profiles.As an option in SMOKE,these online reallocation modules and the vertical allocation module provide a new way for processing emission s in SMOKE.It also improves the ability of SMOKE in temporal and spatial allocation,which is helpful to improve the accuracy of air quality model.