The diurnal change in the vertical distribution of atmospheric 222Rn due to the growth and rise of the stable stratification height in the atmospheric boundary layer

Publisher Summary This chapter analyzes the time-change of 222 Rn vertical distribution in the atmospheric boundary layer, 222 Rn was continuously measured at 3 different heights—30, 150 and 520 m—within a 6-km radius. The air temperature was synchronously observed at 4 different heights—1, 33, 160 and 520 m—at the same site and then the vertical distribution of temperature lapse rates calculated from these measurements. The time-change of 222 Rn vertical distribution could be attributed to the time-change of the vertical distribution of the temperature lapse rate. On the basis of this relationship, the mechanism of 222 Rn vertical mixing has been generalized as a mixing model in the atmospheric boundary layer. The chapter concludes with discussion that the periodic changes of the time-change of 222 Rn vertical distribution and the vertical distribution of temperature lapse rate are the diurnal change and an annual change.