Concentration of radon and its progeny near the surface of the earth at a continental station Pune (18 N, 74 E)

Abstract

In the atmosphere, above the surface of the Earth, the concentrations of radon and its progeny are measured along with the meteorological parameters from December 1997 to December 2000 for a continental location, Pune (18 N, 74 E), India. The concentrations show a maxima in the early morning hours when the turbulence mixing is minimum and a minima in the

afternoon when the turbulence mixing is maximum. The median values of concentration are 9.70 Bq m^-3 and 2.84 Bq m^-3 respectively, for radon and its progeny, during the observation period. Ionization rates in the atmosphere are derived for the same period. It is found that, the ionization rate exhibits a median value of 5.48 ion-pairs cm^-3 s^-1. The diurnal and seasonal

variations in the concentrations of radon and its progeny, and the ionization rate due to radioactivity are found to exhibit correlation with relative humidity, and anti-correlation with temperature. Radioactivity measurements and the derived ion pair production rates are important in modelling the atmospheric electrical conductivity near the Earth's surface.