| With the development of society and economy, air pollution has become increasingly serious. Air quality models, which is an effective instrument employed to research air pollution, have already been widely used. This thesis took Xuzhou, Jiangsu Province, China as the study region. With the help of the third generation air quality model system(Model-3/CMAQ), this thesis has discussed the localization procedure of SMOKE model in Xuzhou area. Meanwhile, it set up a simulation platform for regional air quality in Xuzhou area. On the basis of comparison and verification, a further analysis was conducted on air pollution in Xuzhou in winter by means of this platform. The specific as follows:Firstly, a source separation which was suitable for source of air pollution in Xuzhou area was set up. An explanation was given on the emission source inventory of Xuzhou and exosphere simulation area data and so on. According to the demand of SMOKE model, the localization information of Xuzhou area was collected, the source classification file, zone file, temporal processing file, temporal processing reference file, spatial allocation file, spatial allocation reference file, chemical species reference file and other auxiliary files were compiled and the SMOKE localization model of Xuzhou area was set up. The pollutants inventory(including CO, SO2, NOx, VOC, PM2.5 and PM10) of Xuzhou area was processed as gridding inventory which can be read in by the air quality model by means of the localization model of SMOKE in Xuzhou area.Secondly, combining the model of WRF, SMOKE and CMAQ, this thesis set up the Model-3/CMAQ air quality modeling system of Xuzhou area. Selecting January 2015 as the typical time interval, it compared the simulation results of different time scales with the atmospheric pollution monitoring data(CO, SO2, NO2 and PM2.5) of stations in Xuzhou by means of four layer nested simulation. The simulated values of atmospheric pollutants changes were basically consistent with the monitoring values, high values and low values of simulation were accurate, and the NMB and NME values of CO and PM2.5 are basically under 50%, and SO2 and NO2 simulation performance are relatively poor. But all the results are controlled within a certain error range. NMB and NME are less than 50% of all daily average concentration contrast sites. On the basis of this, the distribution of monthly average concentration of various pollutants in the fourth layer simulation region was analyzed. The monthly average concentration of the fourth simulation region decreased from northwest to southeast.Finally, according to the status of atmospheric pollution in winter of Xuzhou, this thesis simulated the concentration contribution situation of different pollution sources and different areas. The results showed that the point sources made the most contribution to SO2 and NO2 whose rate reached 85.99% and 65.53% respectively; the rate of contribution which mobile sources made to CO reached up to 68.8%; and area sources contributed 68.95% for the rate of PM2.5. In terms of regional contribution, the urban district of Xuzhou and its surrounding areas made the most contribution to the pollutants concentration, especially the pollutants with long-survival time and the capability of being transported over distance such as CO and PM2.5 whose ratio reached up to 59.12% and 53.05% respectively. In addition, this thesis also analyzed the causes of air pollution in Xuzhou area by combining the meteorological principle and other information. |
PDF Full Text Request