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The dynamics of the upper mesosphere and lower thermosphere (UMLT) region is largely influenced by atmospheric solar tides, in addition to gravity waves (GWs) and planetary waves (PWs) that vary at different spatial and temporal scales. The atmospheric solar tides are global scale oscillations having periods, which are sub-harmonics of a solar day, that is, 24, 12, 8, 6 hr and so on. These tides are considered as important dynamical entities responsible for the transmission and deposition of energy from the lower atmosphere to the UMLT region. They play an important role in coupling the lower atmosphere to the mesosphere-ionosphere-thermosphere system. When they propagate upward, their amplitudes increase exponentially because of the decrease of atmospheric density with height. After the attainment of maximum amplitude in the UMLT region, they undergo dissipation. The dissipation can either be mechanical dissipation, like viscosity and turbulence or thermal dissipation, like thermal conduction and infrared cooling (Teitelbaum and Vial., 1981). The tides are classified into migrating and non-migrating components. The migrating tides propagate westward with the apparent motion of the sun and vary only with local time. They are mostly generated by the heating due to the absorption of solar radiation by water vapor in the troposphere, ozone in the stratosphere, and nitrogen and oxygen in the thermosphere. However, the non-migrating tides depend both on local time and longitude (Chapman & Lindzen, 1970;Li et al., 2020) and they can propagate westward, eastward or remain stationary. Longitudinal asymmetry of

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