I have found quite a lot of information about the so-called "flare" model of the propagation of pollutants that enter the atmosphere from a certain height (pipe height). But I could not find any models or justification for the sources of pollution that are on the ground or in close proximity to it (say, at a height of up to 1.5 m - the average height of a person on Earth). It seems to me that the model of propagation of Gaussian pollutants, with a conditional zero instead of the pipe height, is not fully reliable. It would also be interesting to look at the spread of pollutants from the ground level in conditions of buildings of different densities. I'm pretty sure that someone in the world has done something like this. I ask you to share scientific books, articles on this topic, or at least advise which authors should be read in this direction