5:15 PM - 6:30 PM
[PEM03-P03] Study of vertical / seasonal variation of gravity wave in the height range of 15-70km over Syowa Station in Antarctica using Rayleigh/Raman lidar
Keywords:gravity wave, middle atmosphere, lidar
In this study, we investigated monthly mean gravity wave potential energy (Ep) in the height range of 15-70 km from May 2011 to October 2013. Above 35km altitude, Ep was maximized during winter. The seasonal dependence of Ep over Syowa was similar to Ep observed at Davis(69°S,79°E) [Alexander et al., 2011]. Below 35 km altitude, Ep was enhanced in around May, and did not decrease in September. Almost all monthly mean profiles have constant slope above 30 km altitude. Ep increases exponentially with height (increasing rate is approximately exp(z/H); H~7 km is scale height). Furthermore, almost all Ep profiles have a local minimum around 25 km altitude and a local maximum around 20 km altitude. In October 2012, Ep is significantly different from the other Ep profiles. As a result of comparison between the Ep profiles and zonal wind in the NASA MERRA reanalysis data, the reason was probably that weak zonal wind layer in 2012 descends earlier than the other years.