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Using long term measurements of temperature, CO2 vmr and associated cooling rate from SABER (2002–2021) and SD-WACCM simulations (2002–2017) in the 30–100 km altitude region, a study is carried out to evaluate the model simulations. The model simulations are evaluated for their consistency in reproducing long-term trends in the parameters under study as well as their response to solar cycle, QBO and ENSO. The results have shown that WACCM simulations of CO2 agree very well with observations Funding This work is supported by Department of Science and Technology (DST), Government of India through DST-INSPIRE faculty scheme (Faculty Registration No. IFA 20-EAS 84 and DST/INSPIRE/04/2020/001105 ). Authors' contributions Pramitha M and Kishore Kumar K proposed the scientific ideas. Pramitha M and Praveen M completed the analysis, Pramitha M and Kishore Kumar K wrote the manuscript. All authors read and approved the final manuscript. Author agreement statement We the undersigned declare that this manuscript is original, has not been published before and is not currently being considered for publication elsewhere. We confirm that the manuscript has been read and approved by all named authors and that there are no other persons who satisfied the criteria for authorship but are not listed. We further confirm that the order of authors listed in the manuscript has been approved by all of us. We understand that the Corresponding Author is the sole contact Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgements The authors wish to thank NASA's TIMED-SABER team and NCAR's SD-WACCM team for providing data through their respective sites. One of the authors, M. Pramitha, gratefully acknowledges Department of Science and Technology (DST), Government of India for providing the fellowship during the course through DST-INSPIRE faculty scheme (Faculty Registration No. IFA 20- EAS 84 and DST /INSPIRE/04/2020/001105) for the financial support and research opportunity provided for her work. References (54) X. Zhang et al. Global-mean vertical tracer mixing in planetary atmospheres. I. Theory and fast-rotating planets Astrophys. J. (2018) A.I. Semenov et al. The season peculiarities of behaviour of the long-term temperature trends in the middle atmosphere on the mid-latitudes Physics and Chemistry of the Earth, Parts A/B/C (2002) C.Y. She et al. Long-term variability in mesopause region temperatures over Fort Collins, Colorado (41 N, 105 W) based on lidar observations from 1990 through J. Atmos. Sol. Terr. Phys. (2009) P. 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Laštovička Long‐term trends in the upper atmosphere Upper Atmosphere Dynamics and Energetics (2021) View more references Cited by (0) Recommended articles (6) Research article Ascent phase convective heat transfer of a stratospheric-balloon-borne payload Advances in Space Research, 2023 Show abstract Stratospheric ballooning flights are becoming more relevant due to these platforms can place payloads to an altitude above almost 99% of the atmosphere, where the environmental conditions are very similar to the space ones. From a thermal point of view, during the ascent phase convection is very relevant and, despite what a priori may be thought, depending on the element considered, convection may not be negligible at the float phase. With this in mind, the Thermal Analysis Support and Environment Characterization Laboratory (TASEC-Lab) was born. 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