2.1 Conductances

Pedersen and Hall conductances are calculated from the SAMI3 model (Huba et al., 2000; Huba et al., 2008) following the standard relations described e.g. in Maeda (1977). We have not included nonlinear or turbulent sources of Pedersen conductance such as those described by Merkin et al., 2005; Dimant and Oppenheim, 2011 and Wiltberger et al., 2017. SAMI3 solves for the dynamic plasma and chemical evolution of seven ion species (H+, He+, N2+, O+, N+, NO+, and O2+) on a field-aligned magnetic apex coordinate grid (Richmond , 1995) extending up to 88o MLAT. Photoionization is calculated using solar flux from the EUV flux model for aeronomic calculations (EUVAC) by Richards et al. (1994). The Hardy model [Hardy et al.,1985, 1989] provides auroral electron and ion precipitation estimates based on the KP index. The neutral atmosphere is specified by the Horizontal Wind Model 2014 by Drob et al. [2015] and the Naval Research Laboratory’s Mass Spectrometer Incoherent Scatter Model 2000 of neutral atmospheric densities byPicone et al. [2002]. An example of these conductances at 0 UT is shown in Figure 2. In this case, noon is at 0° longitude and therefore is on the right-hand side of the panels.