Abstract
Magnetopause diamagnetic currents arise from density and temperature
driven pressure gradients across the boundary layer. While theoretically
recognized, the temperature contributions to the magnetopause current
system have not yet been systematically studied. To bridge this gap, we
used a database of Magnetospheric Multiscale (MMS) magnetopause
crossings to analyze diamagnetic currents and their contributions across
the dayside and flank magnetopause. Our results indicate that the ion
temperature gradient component makes up to 30% of the ion diamagnetic
current along the magnetopause and typically opposes the classical
Chapman-Ferraro current direction, interfering destructively with the
density gradient component, thus lowering the total diamagnetic current.
This effect is most pronounced on the flank magnetopause. The electron
diamagnetic current was found to be 4 to 12 times weaker than the ion
diamagnetic current on average.