… average of odor hour frequencies? The existance of an odor hour is detected by internal comparison of the hourly mean concentration in a given grid cell  with the … smaller 200000. The reference point must be chosen accordingly. In order to avoid internal rounding errors, specification of calculation grid (left and lower border, … the actual dispersion calculation, any divergence in the provided wind field is internally removed by a simple adjustment ofthe z-components. To keep this …