Observation of Gravity Wave Vertical Propagation through a Mesospheric Inversion Layer

Thurian Le Du (1, 2) , Philippe Keckhut (3) , Alain Hauchecorne (3) , Pierre Simoneau (1)

1 DOTA, ONERA, Université Paris Saclay [Palaiseau]
2 LATMOS - Laboratoire Atmosphères, Milieux, Observations Spatiales
3 STRATO - LATMOS

The impact of a mesospheric temperature inversion on the vertical propagation of gravity waves has been investigated using OH airglow images and ground-based Rayleigh lidar measure- ments carried out in December 2017 at the Haute-Provence Observatory (OHP, France, 44N). These measurements provide complementary information that allows the vertical propagation of gravity waves to be followed. An intense mesospheric inversion layer (MIL) observed near 60 km of altitude with the lidar disappeared in the middle of the night, offering a unique opportunity to evaluate its impact on gravity wave (GW) propagation observed above the inversion with airglow cameras. With these two instruments, a wave with a 150 min period was observed and was also identified in meteorological analyses. The gravity waves’ potential energy vertical profile clearly shows the GW energy lost below the inversion altitude and a large increase of gravity wave energy above the inversion in OH airglow images with waves exhibiting higher frequency. MILs are known to cause instabilities at its top part, and this is probably the reason for the enhanced gravity waves observed above.

Keywords: nightglow; gravity wave; temperature inversion

Domains: Atmospheric and Oceanic Physics [physics.ao-ph]

Thurian Le Du, Philippe Keckhut, Alain Hauchecorne, Pierre Simoneau. Observation of Gravity Wave Vertical Propagation through a Mesospheric Inversion Layer. Atmosphere, 2022, 13 (7), pp.1003. ⟨10.3390/atmos13071003⟩. ⟨insu-03740621⟩