On the Annual Variation of Magnetic Disturbance

摘要: Statistical features of the annual incidence magnetic disturbance, over a very wide range disturbance intensity and latitude, are exhaustively investigated by means K index related ‘planetary’ indices. Two distinct physically significant components identified: ( ) an component, with summer maximum winter minimum; b semi-annual component equinoxial maxima. Soth found in all parts earth. The amplitude increases markedly while that changes little latitude. physical causes two types variation finally considered. conclusions reached is probably caused atmospheric dynamo effect; arises because systematic angle between earth9s axis sun-earth line, along which travel solar particles cause disturbance.