Special Ionospheric Structure Over the Asia‐Australia Sector During the May 2024 Superstorm Recovery Phase

Abstract This study investigates the evolution and characteristics of special ionospheric structures over the Asia‐Australia sector during the recovery phase of the May 2024 superstorm. High‐resolution Total Electron Content (TEC) maps and in situ satellite observations reveal the formation of prominent plasma density peaks along ±40° MLAT, extending from 60°E to 190°E and persisting from 05 UT to 19 UT on May 11. A secondary enhancement emerged around ±20° MLAT between 120°E and 150°E after 14 UT. These structures underwent significant transformations, with the mid‐latitude and low‐latitude features merging into a symmetrical spherical shape after 18 UT and subsequently migrating westward. The ±40° MLAT peaks display an ionospheric origin characterized by significant O + dominance and upward vertical ion drift. The westward plasma drift within a subauroral polarization stream (SAPS) channel is identified as a key contributor to the observed TEC peaks, particularly the stretching of high‐density plasma remnants from the storm‐enhanced density (SED) base region. Furthermore, the study explores the asymmetrical behavior of TEC enhancements around ±20° MLAT and the reshaping of the special ionospheric structure, highlighting the role of equatorial plasma bubbles (EPB) polarization electric fields.