Transmission of Solar Wind Hydromagnetic Energy into the High Latitude Magnetosphere

The relationships of hydromagnetic energy in the band ~20-50mHz, as measured on the ground near a dayside magnetopause field line, to the total magnitude of the interplanetary magnetic field (IMF) are examined. While previous investigations of high latitude hydromagnetic waves have focused on a few selected events, the present results are found from a statistical study of a large sample of data recorded simultaneously at South Pole and its conjugate station at Iqaluit, N.W.T, Canada. Specially, the purpose of the present study is to examine quantitatively previously reported linear relationships between the physical quantities. When a certain selection criterion is imposed, the distribution of signal frequencies f as a function of total IMF magnitude B sub T has two distinct branches for frequency f~20-50mHz. One branch has f independent of B sub T while the other has f as a function of B sub T with approximately a linear relationship, similar to the result of Gul'elmi (1974) from a study based upon lower latitude data and more qualitative, visual criteria.