New investigations of the core ion motion within the high-latitude topside ionosphere and near-Earth magnetosphere, using data from the Dynamics Explorer retarding ion mass spectrometer (RIMS), reveal the existence of significant regions of downward moving O+. The occurrences of downgoing versus upgoing O+ are not clearly separable in terms of either solar zenith angle or Kp but are well distinguished by the direction of the z component of the interplanetary magnetic field (IMF). On average, downflow dominates when IMF Bz0. Combining cross-field convection velocities derived from an empirical convection electric field model with the observed parallel velocities yields a two-dimensional ion velocity field. This velocity field is consistent with a scenario which has O+ of cusp/cleft and auroral zone origin convecting into the polar cap and, because of the dominance of gravitational energy over the upward kinetic energy, falling back into the ionosphere. This provides additional confirmation of the results of studies of the cleft ion fountain. Estimates of the flux of O+ in the upflowing and downflowing regions for &Lgr;≥60¿ give a total upflow of ~6¿1025 ions s-1 for IMF Bz>0 and total upflow and downflow of ~4¿1025 ions s-1 and 1¿1025 ions s-1, respectively, for IMF Bz<0. In all cases the magnitude of the dayside outflow is consistent with previous work on upwelling ions. While the magnitudes vary for high and low Kp the ratios of upward to downward flow are roughly the same at ~1.7. The downflowing O+ shows a correlation with the magnitude of the outflow of light ions in the same region but the cause and effect of this relationship is not distinguishable.