Control of high latitude geomagnetic fluctuations by interplanetary parameters: the role of suprathermal ions

Abstract. We examine the statistical relationships between the interplanetary parameters and spectral power of the geomagnetic fluctuations in the 1–4 mHz frequency band at high latitude stations in two hemispheres. For that, we use a cross-correlative analysis of different combinations of parameters to identify a factor contributing most to the ULF power and to choose (whenever possible) the cross-related keynote controlling parameters. Along with the well-known dependencies of the high latitude pulsation power on the solar wind velocity and variations of the SW dynamical pressure and an additional factor – the flux of solar suprathermal ions with energies about several keV, has been established.