The effects of storm‐enhanced zonal ion drifts and plasmaspheric heat flux on middle‐latitude ionospheric trough

This study examines how enhanced zonal ion drifts and plasmaspheric heat flux influence mid‐latitude ionospheric trough dynamics during geomagnetic storms using the Thermosphere Ionosphere Electrodynamic General Circulation Model coupled with a Subauroral Polarization Streams (SAPS) empirical model. Increasing SAPS‐driven zonal ion drifts from ∼1 to 2 km/s deepened and expanded the trough longitudinally/latitudinally, reducing nighttime TEC by ∼20% within the trough. Ion temperatures doubled to ∼1,600 K under stronger SAPS due to increased frictional heating, while electron density depletion and temperature enhancements showed weaker responses owing to low electron density limiting electron‐ion collisional heating. Doubling plasmaspheric heat flux amplified electron temperature by ∼120% (∼1,200 K) and reduced electron density by ∼80% (∼2 × 10 5  cm −3 ), with minimal ion/neutral temperature changes from limited electron‐neutral thermal coupling. Neutral temperature‐driven atmospheric upwelling decreased O/N 2 ratios, further depleting electron density. These results highlight the critical role of SAPS‐driven ion dynamics and plasmaspheric energy inputs in shaping storm‐time trough morphology through distinct thermal and compositional pathways.