Atmospheric Electrification during South African Dust Storms

Abstract

THIS short note on the variation in the atmospheric electrical charge due to the presence of dust is not intended to be exhaustive, but merely to direct attention to a factor which has a very great influence in modifying the positive potential gradient existing in the atmosphere during fine weather. Very few observations as to the causes of the variations have been recorded, but Prof. Michie Smith seems to have observed (Phil. Mag., vol. xx., p. 456) something of the same kind during dust storms in India. He notes that “the negative electrification was strongest during gusts of dust-laden air,” and, further, “the potential would often run up so rapidly that it was impossible to measure it accurately, whilst during lulls it would often fall almost to zero.”