OBSERVATIONS OF SALT NUCLEI OVER THE MIDWESTERN UNITED STATES

Abstract

The concentrations of salt particles over central Illinois are being monitored through the use of a sodium flame-counter and an impactor. The number of large particles as determined by the impactor has been found to average about two per cubic meter, and high concentrations of the magnitude found over oceans have never been detected. It is concluded that these large salt particles are not found over mid-continents in sufficient numbers to initiate precipitation through a process of condensation and coalescence unless the chain-reaction process is also operative. There is no evidence that these large particles are necessarily carried inland from an oceanic source region.