From the Troposphere to the Thermosphere: Tracking Upward Atmospheric Wave Propagation

Atmospheric gravity waves (GWs) dictate the dynamics of Earth’s atmosphere. These dynamics include perturbing background winds, temperatures and densities, and the deposition of momentum, which results in drag on background mean winds. There have been few complete observations on how they couple from lower to upper atmospheric layers. This project seeks to observe one night of GW coupling upwards into the thermosphere. December 24th, 2018 was chosen due to the quiet magnetic activity from the sun and GW activity observed in the stratosphere; these conditions are optimal for detecting possible coupling to the thermosphere from below. Wind and temperature perturbations can be used to investigate GW activity. For this study, multiple instruments and reanalysis data were used to get data ranging from 5km up to 250-350km. These include the MERRA-2 reanalysis (0-60km), 3D Atmospheric Infrared Sounder (AIRS) (30-40km), Sodium Lidar (80-110km), Rayleigh Lidar (40-80km) and the Scanning Doppler Imager (SDI) (250-350km). Observations also show both disturbances to the polar night jet in the stratosphere and strong semidiurnal tides present in the mesosphere, which provides exciting conditions for possible GW sources in the thermosphere.