Effects of coronal hole flows loaded by material from a disappearing filament Original Research Article

MHD self-consistent simulation results are presented for the case of a sequence of pulses with increases in velocity and density of the solar wind at small heliodistances, where they are introduced as lower boundary conditions. These pulses model coronal hole dynamics (velocity increase) and a disappearing filament (density increase). To support the model results, the observations of May 17–19, 1999, event are used. It was concluded, on the basis of simulations, that a strong geomagnetic storm can result from an interaction between fast and dense fluxes in the heliosphere, even if each flux separately is not geoeffective at all.