Dispersion within an urban area

[sahil.bhandari]

It was mentioned that for higher resolution problems (lower "upper limit" of height of particles being tracked) we need more particles to represent the system since the system is less well mixed. This seems like a situation we might encounter when analyzing an urban region of the order of 100 square kilometers and dense source distribution. So, to confirm, for such a system, would we use a very low height (~50m/0.05MLH) and very high resolution?

[Fantine]

In general, we need to increase particles in the simulation as going to a finer grid resolution for short-range (or say, urban scale) applications. This kind of scale is usually in a few kilometers or sub-kilometer resolution. Section 17.4 of the tutorial will discuss this. The tracer experiment in that section is Sagebrush using a sampling network the most distance of 1.6 km downwind of the source. The grid is set to 25 m in vertical and 0.001 deg (~100 m) in horizontal.