scostep 2010 (stp12) - Leibniz-Institut für Atmosphärenphysik an der ...

STP12 Abstracts
Berlin, 12 - 16 July 2010
SCOSTEP Symposium 2010
Simultaneous observation of quasi 16-day wave in the mesospheric winds and
temperature over low-latitude with SKiYMET radar
Das Siddarth Shankar
Space Physics Laboratory, VSSC, Trivandrum
This paper presents for the first time the seasonal characteristics of 16 day planetary
wave on mesospheric temperature and winds simultaneously over a low-latitude station
Thumba (8.5 o N, 76.5 o E) using meteor radar. Four-years (2005-2008) of meteor winds and
temperature data are used for the present study. It is observed that the amplitude of 16-day
wave in zonal component is more than that of meridional. Further analysis shows that
westerly phase of zonal wind is more favorable for the 16-day waves. The maximum
amplitude in mesospheric temperature is observed during January-February and August-
September. Climatology of 16-day wave shows the variability of semi-annual oscillation
(SAO) on mesospheric temperature but not on winds. The vertical amplitude structure of
zonal component shows the maximum amplitude at ~ 88-92 km with constant phase. It is also
noticed that zonal and meridional wind are in phase, whereas as temperature leads zonal wind
by 5±1 days. The significant of the present result shows the wave characteristics, effect of
background wind and manifestation of SAO on their propagation behavior. It is envisaged
that the present result will contribute to our understanding of the dynamics of the MLT region
at low latitude in the northern hemisphere. The detail results will be discussed in the
upcoming symposium.