ICON Observation
We also used the ion drift data from the NASA ICON mission [Immel et al., 2018] for a comparison with the MAGE simulation results. ICON is an equatorial mission for studying equatorial ionospheric connection to the lower atmosphere. It carries ion velocity meter (IVM), which measure ion drift, density, and composition [Heelis et al., 2017]. In this study, we will only examine the IVM ExB meridional ion drift, which at the magnetic dip equator is vertically upward pointing. IVM ExB ion drifts are decomposed into magnetically zonal (horizonal, eastward is positive) and meridional (within the magnetic meridian plain, upward is positive). Hence, at the low latitudes, the meridional ion drift is a good approximation of the vertical ion drift. IVM samples the ion drift at 1 second cadence. The IVM data quality depends on the ion density. In our selected cases, we only used the data from noon to evening magnetic local time when the ion density is relatively high.