SA13A-2316
Effect of Gravity Waves Generated in the Monsoon Region on Polar Mesospheric Clouds
Monday, 14 December 2015
Poster Hall (Moscone South)
Brentha Thurairajah1, Scott Martin Bailey1 and Justin N Carstens2, (1)Virginia Polytechnic Institute and State University, Blacksburg, VA, United States, (2)Virginia Polytechnic Institute and State University, Bradley Department of Electrical and Computer Engineering, Blacksburg, VA, United States
Abstract:
Gravity Waves (GWs) play an important role in both the formation and destruction of polar mesospheric clouds. In summer, while vertically propagating GWs induce a residual circulation that cools the summer mesosphere and therefore supports the formation of PMCs, observation and modeling studies have also shown that short period GWs can additionally destroy PMCs. In this study we analyze the effect of non-vertical propagation of GWs on PMCs using temperature data from the SABER instrument on TIMED satellite and PMC occurrence frequency from the CIPS instrument on the AIM satellite. During the 2007 PMC season, time series of GWs over the monsoon region at 50 km and PMCs over the polar region at 84 km have a correlation coefficient of 0.9. SABER GW amplitude and momentum flux over the monsoon region show a poleward tilt with altitude. This slanted structure suggests a poleward, but non-vertical, propagation of GWs facilitated by the easterly winds associated with the monsoon circulation, thus indicating a possible source of high latitude middle atmospheric GWs.
