Interannual and seasonal effects of sudden stratospheric warming events on gravity wave activity

A significant correlation is found between the modulation of gravity wave activity and the level of disturbance in the middle atmosphere associated with sudden stratospheric warming (SSW) events. We report the variability of stratospheric and mesospheric (40-50 km) gravity wave activity, as measured at the Lidar Research Laboratory-Poker Flat Research Range, Chatanika, Alaska (65N, 147W), and the wind speed during SSWs. Using the Rayleigh lidar technique, measured relative density profiles are used to determine nightly temperature and density profiles. Gravity wave activity is characterized by calculating the potential energy density. The fluctuations in the lidar density profile and measurements of the buoyancy frequency are used to calculate potential energy density. Satellite and reanalysis data are used to characterize the synoptic conditions of the Arctic middle atmosphere and SSWs.