大气扩散模式 是一种用电脑仿真空气污染物如何扩散到附近的大气中。并且知道污染源附近的空气品质，是否会危害人体。这对许多工业区的规划非常重要，因为必须要评估工厂所排出的废气是否会引响附近人民的健康。
再用电脑仿真大气扩散模式之前，必须要输入一些变量:

Atmospheric dispersion modeling is the mathematical simulation of how air pollutants disperse in the ambient atmosphere. It is performed with computer programs that solve the mathematical equations and algorithms which simulate the pollutant dispersion. The dispersion models are used to estimate the downwind ambient concentration of air pollutants or toxins emitted from sources such as industrial plants, vehicular traffic or accidental chemical releases. They can also be used to predict future concentrations under specific scenarios (i.e. changes in emission sources). Therefore they are the dominant type of model used in air quality policy making. They are most useful for pollutants that are dispersed over large distances and that may react in the atmosphere. For pollutants that have a very high spatio-temporal variability (i.e have very steep distance to source decay such as black carbon) and for epidemiological studies statistical land-use regression models are also used.