The polarity of thunderclouds

Abstract

In a paper on ‘'The Electric Fields of South African Thunderstorms,” Mr. J. Craib and the writer described some observations made at Somerset East during 1926, from which it was concluded that the majority of the storms examined were of positive polarity. The study of these storms has been continued during the present year and a number of fresh points have been examined. In this paper some further evidence as to the polarity of thunderstorms will be discussed. After the observations had been made, an important paper by Dr. G. C. Simpson appeared in which the effects to be expected from a cloud of negative polarity, formed according to the breaking-drop theory, were discussed and considered to be in agreement with our 1926 measurements. I hope to be able to show, however, that our original conclusion as to the polarity of the clouds was correct.