Fig. 7

for a representative auroral zone crossing, a shows along-track drift estimation using the SLIDEM methodology using various methods. The gray plot in a shows the along-track ion velocity estimate derived using Eq. (10), where effective ion mass has been estimated using IRI-2016. Meanwhile, the black plot shows the detrended version of the gray plot, to normalize it such that ion drift at low latitudes is around zero. b Shows a different auroral zone crossing on the same day, with the SLIDEM ion velocity output (red) alongside Weimer 2005 ion drift estimations (blue)