Mechanisms for Enhanced Gravity Wave Activity during Stratospheric Sudden Warmings

We observe enhanced gravity wave (GW) activity in the stratosphere during stratospheric sudden warming (SSW) events in the Northern Hemisphere in January and February 2008 using GPS RO temperature retrievals and independent EOS/Aura HIRDLS temperature data. We explore the possible mechanisms (including both GW propagation considerations and wave source considerations) for such GW enhancements during SSWs using GW ray-tracing analysis and various diagnostics techniques. We will also show the newest GW and SSW analysis results for the 2008/09 Northern Hemisphere winter.