The diurnal and seasonal changes in short-lived radon-thoron daughters' concentrations in the coastal and inland regions of India and their possible relation to regional climatology

Abstract

The levels of Pb-214 (Ra-B) and Pb-212 (Th-B) in surface air at two coastal stations (Bombay and Thumba) and at a third high-altitude station (Gulmarg) in India are presented. A seasonal variation in activity at the coastal stations with winter maximum and summer minimum and the absence of a similar variation at the high-altitude station at Gulmarg is discussed. From a study of the relevant meteorological data, it is concluded that at the coastal stations, the major factor influencing the activity levels is likely to be the stability of the lower atmosphere, advective effects possibly playing a secondary role. At Gulmarg, however, factors affecting emanation from the soil, like rainfall, snowfall, etc., could be significant.