This research aims to understand the importance of lower thermospheric atomic oxygen on the upper thermosphere. O number densities between 95-100 km from WACCM-X are much closer to the observations from SABER instrument on TIMED satellite as compared to those from MSIS. We show in this study that the correction of the lower boundary atomic oxygen yields better agreement between GITM and GUVI O/N2 in the upper thermosphere .
Malhotra, G., Ridley, A. J., Marsh, D. R., Wu, C., Paxton, L. J., & Mlynczak, M. G. (2020). Impacts of Lower Thermospheric Atomic Oxygen on Thermospheric Dynamics and Composition Using the Global Ionosphere Thermosphere Model. Journal of Geophysical Research: Space Physics, e2020JA027877. https://doi.org/10.1029/2020JA027877
This research aims to understand the influence of lower thermospheric atomic oxygen ([O]) and dynamics on the thermospheric Semi Annual Oscillation (SAO). [O] number densities between 95-100 km from WACCM-X are much closer to the observations from SABER instrument on TIMED satellite as compared to those from MSIS. We compare the phase and amplitude of SAO from different simulations with empirical models and observational datasets, and explore different mechanisms that can improve the SAO in IT models.
Malhotra, G., Ridley, A., Jones, M., (2021) Impacts of Lower Thermospheric Atomic Oxygen and Dynamics on Thermospheric Semiannual Oscillation using GITM and WACCM-X, Journal of Geophysical Research: Space Physics
The goal of this research study is to understand the sensitivity of the IT region to the spatial variation of Kzz. This is done using the IT model, GITM, with different settings and spatial distributions for Kzz. We introduce latitudinal bands (longitudinally uniform) of 30 degrees width at equatorial and polar latitudes during different seasons similar to the previous observations in literature. We investigate the mechanisms through which a non-uniform global distribution of Kzz can alter the dynamics and thermal structure of the thermosphere, and how these effects compare to when a globally uniform value of Kzz is used.
Malhotra, G., Ridley, A.J. (2021). Impacts of Spatially Varying Eddy Diffusion in the Lower Thermosphere on the Ionosphere and Thermosphere using GITM - Sensitivity Study. and A.J. Ridley, Y. Deng, G. Tóth, The global ionosphere–thermosphere model, Journal of Atmospheric and Solar-Terrestrial Physics, Volume 68, Issue 8, 2006, Pages 839-864, ISSN 1364-6826, https://doi.org/10.1016/j.jastp.2006.01.008.
