10:55 - 12:20
Conference Room
Oral presentations
Gravity wave momentum fluxes and their role in low latitude MLT dynamics using long term continuous meteor radar observations
Maria Antonita Thithonis1, Geetha Ramkumar2, Karanam Kishore Kumar2
1Space Science Program Office ISRO, Bangalore, India
2Space Physics Laboratory, Vikram Sarabhai Space centre, ISRO, Trivandrum, India

In the vertical coupling of the different regions of the Earth’s atmosphere, whole atmospheric science community unanimously concurs the profound role played by gravity waves. Divergence/convergence of the energy and momentum fluxes carried by the gravity waves accelerate/ decelerate the mean flow which in turn partly responsible for the maintenance of QBO and SAO in the stratospheric and mesospheric region, which are the characteristic features of the equatorial middle atmosphere. To quantify the role of short period gravity waves in controlling the dynamics of the MLT region, more than ten years of continuous meteor radar observations during June 2004- Dec 2013 are extensively used. The gravity wave momentum fluxes in the Mesosphere Lower Thermosphere (MLT) region are estimated over Trivandrum (8.5°N, 78°E), a low-latitude station in India during aforementioned period. The radial velocity variances in the 82-98 km height region, which are mainly caused by the gravity waves, measured by the meteor radar are used to determine the gravity wave momentum fluxes. Using the estimated gravity wave momentum fluxes their contribution in driving the mesosphere semiannual oscillation (MSAO) during June 2004 to Dec 2013 is quantified. The results will be discussed in detail in the conference.


Reference:
Mo-AM-2-O-04
Session:
Observations I
Presenter/s:
Maria Antonita Thithonis
Topic:
1) Observed trends and long term variations in the middle atmosphere
Presentation type:
Oral communication 15 min
Room:
Conference Room
Chair/s:
Stanley Solomon
Moderator/s:
Christian von Savigny
Date:
Monday, 19 September 2016
Time:
11:50 - 12:05