Fig. 8
From: Sunlight effects on the 3D polar current system determined from low Earth orbit measurements
Estimates of field-aligned and total horizontal currents for three different combinations of magnetic coordinates: Dipole coordinates and components (left column), apex coordinates and dipole components (middle column), and apex coordinates and components (right column). The plots are based on data from Swarm A only, with \(B_z < -1\) nT, and the terminator crossing the noon–midnight meridian poleward of \(\pm 75^\circ\). The truncation levels are \(N_V, M_V = 35, 5, N_T, M_T = 60, 5\). The currents become stronger and better defined with consistent use of apex coordinates. The scale of the field-aligned currents is the same as in previous figures