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TIE-GCM model output used in the study “Modulation of Thermospheric Circulation by Lower-Thermospheric Winter-to-Summer Circulation: The Atmospheric Gear Effect” (Wang et al., 2025). This dataset includes key variables used to analyze the dynamic and thermodynamic coupling between the lower thermosphere and mesosphere. 

A new version of the US National Science Foundation National Center forAtmospheric Research (NSF NCAR) thermosphere-ionosphere-electrodynamicsgeneral circulation model (TIEGCM) has been developed and released. Thispaper describes the changes and improvements of the new version 3.0since its last major release (2.0) in 2016. These include: 1) increasingthe model resolution in both the horizontal and vertical dimensions, aswell as the ionospheric dynamo solver; 2) upward extension of the modelupper boundary to enable more accurate simulations of the topsideionosphere and neutral density in the lower exosphere; 3) improvedparameterization for thermal electron heating rate; 4) resolvingtransport of minor species N(2D); 5) treating helium as a major species;6) parameterization for additional physical processes, such as SAPS andelectrojet turbulent heating; 7) including parallel ion drag in theneutral momentum equation; 8) nudging of prognostic fields near thelower boundary from external data; 9) modification to the NO reactionrate and auroral heating rate; 10) outputs of diagnostic analysis termsof the equations; 11) new functionalities enabling model simulations ofcertain recurrent phenomena, such as solar flares and eclipse. Wepresent examples of the model validation during a moderate storm andcompare simulation results by turning on/off new functionalities todemonstrate the related new model capabilities. Furthermore, the modelis upgraded to comply with the new computer software environment at NSFNCAR for easy installation and run setup and with new visualizationtools. Finally, the model limitations and future development plans arediscussed. 

Key Points Validation of ionospheric total electron content (TEC) by the state‐of‐the‐art ionospheric models hosted by NASA Community Coordinated Modeling Center, National Oceanic and Atmospheric Administration Space Weather Prediction Center, and NASA Jet Propulsion Laboratory (JPL) Multiple metrics and skill scores are used to assess the performance of ionospheric models in capturing storm time TEC anomaly GLObal Total Electron Content and JPL Global Ionospheric Map perform best, and physics‐based models perform better than the empirical model in capturing storm TEC variations 

Abstract The migrating diurnal tide (DW1) is one of the dominant wave motions in the mesosphere and lower thermosphere. It plays a crucial role in neutral atmosphere and ionosphere coupling. The DW1 can vary over a range of time scales from days to years. While the long‐term variability of the DW1 is mainly attributed to the source and background atmosphere variability, the driving mechanism of short‐term DW1 variability is still openly debated. Herein the daily structure of the DW1 is extracted from observations using a novel multi‐satellite estimation technique and compared with model simulations (NOGAPS‐ALPHA and WACCM‐X). Both the observations and the models show that the day‐to‐day variability of the DW1 is a persistent and ubiquitous feature. The standard deviation peak of DW1 amplitudes, which is used to measure the maximum variability, is generally aligned with the DW1 amplitude peak. This result indicates that the day‐to‐day variability of the DW1 reflects global‐scale changes rather than local excitation of diurnal oscillation. The spatial lag‐correlation analysis of the diurnal (1,1) and (1,2) Hough modes suggests that the day‐to‐day variability of the diurnal (1,1) Hough mode is likely driven by variability in the lower atmosphere and the source of day‐to‐day variability of the (1,2) mode is uncertain. The significant correlation of the DW1 day‐to‐day variability between the NOGAPS‐ALPHA and the multi‐satellite estimation techniques also indicates that the model is capable of reproducing the DW1 structure on a daily basis.