Dataset for "Abnormal ionospheric storm phases and significant equatorial plasma bubbles over the Asian sector during the 16 April 2025 geomagnetic storm"

This dataset provides the observational data and model outputs supporting the study of abnormal ionospheric storm phases and significant equatorial plasma bubbles (EPBs) during the 16 April 2025 geomagnetic storm over the Asian sector. The dataset includes multi-instrument observations from the Chinese Meridian Project, including dual-channel optical interferometer (DCOI) measurements of thermospheric neutral winds, Sanya Incoherent Scatter Radar (SYISR) observations of ionospheric plasma parameters, and ground-based GNSS observations of total electron content (TEC) and ionospheric irregularities. Complementary satellite observations from GUVI/TIMED, Swarm, and COSMIC-2 are also included to characterize storm-time ionospheric and thermospheric responses. The dataset contains processed GNSS TEC, ROTI (Rate of TEC Index) maps, electron density observations, ionospheric plasma drift measurements, thermospheric composition variations, and related diagnostic parameters used to investigate the abnormal “negative-then-positive” ionospheric storm phases and the development of post-sunset equatorial plasma bubbles. In addition, model simulation results from the Prompt Penetration Electric Field Model (PPEFM) are provided to examine the electrodynamic mechanisms responsible for the observed disturbances. All datasets have been processed and prepared for reproducibility of the analyses presented in the associated publication. These data support investigations of storm-time magnetosphere-ionosphere-thermosphere coupling processes and low-latitude ionospheric variability during extreme geomagnetic disturbances.