The influence of the weather on the concentration of nuclear bomb debris in air

Abstract

Daily measurements of the concentration of nuclear bomb debris in air in terms of gross β radioactivity have been made by the Norwegian Defense Research Establishment at a number of places in Norway, The weather developments were examined for samples collected during the period July 1, 1957, to June 30, 1959. It was found that low radioactivity was predominantly associated with centers of low pressure, with influx of arctic air, or with rainy weather. High radioactivity was predominantly associated with centers of high pressure, with influx of warm subtropical air, or with marked frontal passages. This indicates that concentrations of nuclear bomb debris become adjusted to weather conditions fairly rapidly. The statistics seem to be satisfactorily explained if the principal removal agent is precipitation and the principal ways of replenishment are vertical downward transport in high-pressure centers and overturning of air in frontal zones. The low concentration in arctic air may well be due to a short residence time of air in the Arctic. It need not reflect a lack of downward flux in this area.