Burst of Unusual Quasi-10 day Wave During the 2019 Southern Sudden Stratospheric Warming
<div> <p>An unusual sudden stratospheric warming (SSW) occurred in the Southern hemisphere in September 2019. Ground-based and satellite observations show the presence of a transient westward-propagating quasi-10 day planetary wave with zonal wavenumber one during the SSW.&#160;The planetary wave&#160;activity&#160;maximizes in the MLT region&#160;approximately 10 days after the SSW onset. Analysis indicates the&#160;quasi-10 day planetary wave&#160;is symmetric about the equator which is contrary to theory for such planetary waves.&#160;</p> </div><div> <p>Observations from MLS and&#160;SABER&#160;provide a unique opportunity to study the global structure and evolution of the symmetric&#160;quasi-10 day wave&#160;with observations of both geopotential height&#160;and temperature during these unusual atmospheric conditions. The space-based measurements are combined with meteor radar wind measurements from Antarctica, providing a comprehensive view of the quasi-10 day wave activity in the southern hemisphere during this SSW. We will also present the results of our mesospheric and lower thermospheric analysis along with a preliminary analysis of the ionospheric response to these wave perturbations.</p> </div>