Abstract
Elevated-source dispersion is compared with simultaneous surfacesource dispersion. The analysis starts from the finding that the tracer cloud height generally varies with the downwind distance. Over a complicated terrain such as Kainan City the Pasquill stability of elevated-source dispersion is high and that of the corresponding surface-source dispersion is somewhat lower. Over a relatively flat terrain as Oita City the Pasquill stability for an elevated source is in general low or very low under weather conditions not much different from those at the Kainan City experiment. While the Pasquill stability for a surface source is definitely higher, which is reverse to the dispersion over Kainan City.
The height of tracer cloud generally increases with the downwind distance, irrespectively of the elevated or the surface source. The rise of the tracer is more remarkable over a sloped terrain.
