Research Of Urban Air Quality Numerical Prediction And Forecasting Display Based On GIS

In recent years, people have seriously damaged the environment for pursuing high-speed economic development. Environmental issues are increasingly prominent and seriously threaten people’s subsistence and development. Especially air pollution is negative for human’s physical and psychological health. So, it is necessary that using advanced and scientific technology to forecast urban air quality. According to the forecasting of urban air quality, people could intuitively realize air pollution condition and take effective control measures timely.GIS is a new subject, which includes geography、mathematics、computer science、information science、topography and management science. Using the advantages of GIS in space analysis and space treatment to solve environmental problem is paid close attention by many domestic and overseas environmentalists, and becomes a research hotspot in current air quality forecasting.Based on single pollution point diffusion simulation, this thesis combined GIS and the atmospheric pollution diffusion model, and then selected some urban region as evaluation region to study the prediction of air pollution under the condition of multi pollution points,and realized the visualization of prediction results. Firstly, this thesis preprocessed the required data. Referring to the position of pollution points, it reasonably selected the range of evaluation region, and then acquired the coordinate values of pollution points and grid cells of the evaluation region, and got the environmental parameters and the emissions data of pollution sources. Secondly, this thesis proceeded with the analog computation of pollutant concentration. For making simulation result truly reflect the pollution condition of urban air, it comprehensively considered many kinds of impact factors of atmospheric pollution diffusion,and selected Gaussian diffusion model to calculate the pollutant concentration of evaluation region under the condition of every pollution point. According to analyzing the pollution concentration contribution of every pollution source to the grid cell, this thesis relied on the environmental impact parameters of every pollution source to improve the original concentration accumulation method and make it more effective. Using the two methods to calculate the concentration and compare their results, it shows that the improved concentration accumulation method is more effective and superior. Lastly, this thesis drew the isolines of two kinds of air pollution prediction results, and overlaid them with urban map on ArcGIS to realize the visualization of simulation results. The result shows that the forecasting of urban air quality is more convenient to realize the air pollution condition for people at macro level.