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Abstract Nitric oxide (NO) emission via 5.3 µm wavelength plays dominant role in regulating the thermospheric temperature due to thermostat nature. The response of NO 5.3 mm emission to the negative pressure impulse during November 06–09, 2010 is studied by using Sounding of Atmosphere by Broadband Emission Radiometry (SABER) observations onboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite and model simulations. The TIMED/SABER satellite observations demonstrate a significant enhancement in the high latitude region. The Open Geospace General Circulation Model (OpenGGCM), Weimer model simulations and Active Magnetosphere and Planetary Electrodynamics Response Experiment measurements exhibit intensification and equatorward expansion of the field-aligned-currents (FACs) post-negative pressure impulse period due to the expansion of the dayside magnetosphere. The enhanced FACs drive precipitation of low energy particle flux and Joule heating rate affecting whole magnetosphere–ionosphere–thermosphere system. Our study based on electric fields and conductivity derived from the EISCAT Troms$${\o }$$ $ø$radar and TIEGCM simulation suggests that the enhanced Joule heating rate and the particle precipitations prompt the increase in NO cooling emission. 

Abstract We report the first simultaneous, common‐volume lidar observations of thermosphere‐ionosphere Fe (TIFe) and Na (TINa) layers in Antarctica. We also report the observational discovery of nearly one‐to‐one correspondence between TIFe and aurora activity, enhanced ionization layers, and converging electric fields. Distinctive TIFe layers have a peak density of ~384 cm⁻³and the TIFe mixing ratio peaks around 123 km, ~5 times the mesospheric layer maximum. All evidence shows that Fe⁺ion‐neutralization is the major formation mechanism of TIFe layers. The TINa mixing ratio often exhibits a broad peak at TIFe altitudes, providing evidence for in situ production via Na⁺neutralization. However, the tenuous TINa layers persist long beyond TIFe disappearance and reveal gravity wave perturbations, suggesting a dynamic background of neutral Na, but not Fe, above 110 km. The striking differences between distinct TIFe and diffuse TINa suggest differential transport between Fe and Na, possibly due to mass separation.