Volumes and Issues  Contents of Issue 11  
Ann. Geophys., 24, 2877-2889, 2006
www.ann-geophys.net/24/2877/2006/
© European Geosciences Union 2006


Vertical propagation characteristics and seasonal variability of tidal wind oscillations in the MLT region over Trivandrum (8.5° N, 77° E): first results from SKiYMET Meteor Radar

V. Deepa, G. Ramkumar, M. Antonita, K. K. Kumar, and M. N. Sasi
Space Physics Laboratory, Vikram Sarabhai Space Centre, Trivandrum 695022, India

Abstract. Tidal activity in the Mesospheric Lower Thermosphere (MLT) region over Trivandrum (8.5° N, 77° E) is investigated using the observations from newly installed SKiYMET Meteor Radar. The seasonal variability and vertical propagation characteristics of atmospheric tides in the MLT region are addressed in the present communication. The observations revealed that the diurnal tide is more prominent than the semi/terdiurnal components over this latitude. It is also observed that the amplitudes of meridional components are stronger than that of zonal ones. The amplitude and phase structure shows the vertical propagation of diurnal tides with vertical wavelength of ~25 km. However, the vertical wavelength of the semidiurnal tide showed considerable variations. The vertical propagation characteristics of the terdiurnal tide showed some indications of their generating mechanisms. The observed features of tidal components are compared with Global Scale Wave Model (GSWM02) values and they showed a similar amplitude and phase structure for diurnal tides. Month-to-month variations in the tidal amplitudes have shown significant seasonal variation. The observed seasonal variation is discussed in light of the variation in tidal forcing and dissipation.

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Citation: Deepa, V., Ramkumar, G., Antonita, M., Kumar, K. K., and Sasi, M. N.: Vertical propagation characteristics and seasonal variability of tidal wind oscillations in the MLT region over Trivandrum (8.5° N, 77° E): first results from SKiYMET Meteor Radar, Ann. Geophys., 24, 2877-2889, 2006.   Bibtex   EndNote   Reference Manager