Abstract
In this presentation, we seek to understand the altitudinal response of
the auroral E-region neutral wind to substorms using observations from
the Poker Flat Incoherent Scatter Radar (PFISR). Zou et al. (2009)
presented different nighttime ion drift pattern associated with three
different types of substorm events whose onset locations were at, to the
east and to the west of PFISR. In addition, Zou et al. (2021) presented
different types of latitudinal responses of the F-region neutral wind to
substorm events and suggested that the response is highly local time
dependent. While these two studies give much insight on the F region ion
and neutral responses during substorm events, the E region neutral wind
response is not well-understood. Previous studies showed that during
disturbed conditions E-region winds, in particular below 110 km, are
larger than what tidal theory predicts, while the winds in the upper
E-region shows strong impacts from the convection flow. We select events
whose onset locations are over the PFISR radar site, but in different
MLT sectors using the SuperMag data product during 2010-2019. We present
a superimposed epoch analysis of three different types of events after
subtracting the quiet background neutral winds. This study will further
our understanding of the contribution in a statistical view from forces
that are associated with the E-region wind variation during substorm
events during different MLT sectors and spanning the altitude range from
90-130 km.