Observation of Gravity Wave Vertical Propagation through a Mesospheric Inversion Layer

International audienceThe impact of a mesospheric temperature inversion on the vertical propagation of gravitywaves 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). Thesemeasurements provide complementary information that allows the vertical propagation of gravitywaves to be followed. An intense mesospheric inversion layer (MIL) observed near 60 km of altitudewith the lidar disappeared in the middle of the night, offering a unique opportunity to evaluateits 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 identifiedin meteorological analyses. The gravity waves’ potential energy vertical profile clearly shows theGW energy lost below the inversion altitude and a large increase of gravity wave energy abovethe inversion in OH airglow images with waves exhibiting higher frequency. MILs are known tocause instabilities at its top part, and this is probably the reason for the enhanced gravity wavesobserved above