Rate and chemistry of wet deposition derived from time series of natural radioactivity

Time series of natural radioactivity as used in this paper provide a powerful tool for the study of the wet removal processes. They are particularly useful if the mechanisms and the efficiency of the removal processes are to be investigated during individual precipitation events. A comparison of the atmospheric inventory with the radioactivity flux to the ground provides additional information about the tracer balance and the processes in question. The behavior of the tracer used is different from that of many other constituents of the atmosphere inasfar as it is continuously produced within the atmosphere by radioactive decay of the noble gas 222Rn. A continuation of this work therefore has to include other atmospheric constituents which do not show this particular behavior. From the methods available for a measurement of other constituents the electrical conductivity measurement has been chosen because it provides the same time resolution as the radioactivity measurement. Instrumentation for continuous conductivity measurements during precipitation has been developed, and preliminary results are available