The MSP sweeps along the magnetic meridian from 80° north to 80° south of zenith at a scan period of 20 s. The optical data were taken by a multi-channel Meridian Scanning Photometer (MSP) located at Ny-Ålesund (NYA, 78.9°N, 12☎). Here we will demonstrate a one-to-one relationship between ion upflow events observed by ESR and precipitation bursts associated with PMAFs moving over the radar. When IMF B Z has a southerly orientation, intermittent sequences of poleward moving auroral forms (PMAFs) occur at a repetition rate of anything from 2–15 minutes, but an average of ∼8 minutes have often been reported. From extensive studies of daytime auroral activities we know that cusp/cleft auroral activities have a transient nature, which have been linked to the quasi-periodic nature of magnetopause flux-transfer events. found F-region upflows to be strongly correlated with low energy precipitation in cusp, cleft and mantle regions. Using DMSP conjunctions of ESR Ogawa et al. From the ground we can observe the initial stage of ion outflow events by the incoherent scatter radar technique. In particular we will refer to ion upflow as we consider the altitude range 200–600 km observed by EISCAT Svalbard Radar (ESR), and overhead low energy electron precipitation from the 630.0 nm auroral emission. In this paper we examine time continuous direct measurement of key relevant parameters, within the invariant latitude and MLT to which prior work draws attention. found that the location of the cusp maximum was at ∼78° ILAT independent of IMF B Z orientation. showed that maximum number flux values occurred in the 09–15 MLT region near ∼78° ILAT. This was surprising as the efficiency of energy and momentum transfer is very much under control of the IMF orientation. revealed a strong correlation between the hourly averaged value of IMF B Z and the invariant latitude of the peak of O + flux, but the correlation between B Z and the flux of upwelling ions was found very poor. Although the energy transfer mechanism is yet not understood, the largest fluxes of ion outflows occur in relation to low energy electron precipitation and daytime auroral activities. mapped the occurrence of upflowing ions to a zone closely related to the auroral oval. The phenomenon of ion outflow has been studied by satellites in the high-altitude magnetosphere for nearly 30 years.
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