Singh, RamScipión, DannyKuyeng, KarimCondor Patilongo, PercyDe la Jara, CésarVelasquez, Juan PabloFlores, RobertoIvan, Edwar2025-01-062025-01-062024-11-14Singh, R., Scipión, D., Kuyeng, K., et al. (2024). Ionospheric Disturbances Observed Over the Peruvian Sector During the Mother’s Day Storm (G5-Level) on 10–12 May 2024.==$Journal of Geophysical Research: Space Physics, 129$==(11). https://doi.org/10.1029/2024JA033003index-oti2018http://hdl.handle.net/20.500.12816/5663This article presents the recent extreme and rare G5-level geomagnetic storm (Mother's Day Storm) effects on the equatorial and low-latitude ionosphere observed at the Peruvian sector by the Jicamarca (11.9°S, 76.8°W, magnetic dip 1°N) incoherent scatter radar and associated instruments. This storm was produced by multiple Earth-directed coronal mass ejections, which generated significant modifications in the Earth's magnetic field, leading to the Sym-H of ∼−518 nT. On the dayside, due to the strong eastward penetration electric field, vertical plasma drift and equatorial electrojet (EEJ) enhanced for 2–3 hr and remained consistent at values of ∼95 m/s and 260 nT between 1700 and 1900 UT (1200 and 1400 LT). At the same time, vertical E x B plasma drift uplifted the equatorial ionosphere, producing the dusk-side super plasma fountain and transferring electron density to higher latitudes. A huge increase (∼1,325%) in electron density (from 11 to 142 TECu) is observed at low and mid-latitudes from ∼20°S to 50°S between 2000 and 0400 UT (1500–2300 LT). The strong westward penetration electric field suppressed pre-reversal enhancement, leading to downward plasma drift (∼−96 m/s) at around 2400 UT (1900 LT). Overnight, vertical plasma drift fluctuated between ±90 m/s, and the combined effect of penetration and disturbance dynamo electric fields caused a significant increase (∼530 km) in ionospheric virtual height. In the main and early recovery phase, consistent short- and long-duration electric field disturbances persisted for approximately 30 hr, with periods of ∼48 and 90 min.application/pdfenginfo:eu-repo/semantics/closedAccessG-5 magnetic stormPrompt penetration electric fieldElectrodynamics of equatorial ionospherePlasma driftIncoherent Scatter Radarinfo:eu-repo/semantics/articlehttps://purl.org/pe-repo/ocde/ford#1.03.00https://purl.org/pe-repo/ocde/ford#1.03.08Journal of Geophysical Research: Space Physicshttps://doi.org/10.1029/2024JA033003