Gravity Wave Energy Baselines (∼30–110 km) Established From Lidar Observations at McMurdo (77.84°S, 166.67°E), Antarctica: Energy Dissipation and Constituent Diffusion

Abstract

Lidar observations above McMurdo, Antarctica from 2011 to 2024 are used to characterize gravity wave (GWs) potential energies () in the mesosphere and lower thermosphere (MLT). Alongside characterizations in the middle atmosphere (30–70 km), the GW baselines show dissipation at all altitudes from 30 to 110 km. Stronger dissipation occurs for GWs with shorter and in regions of lower , likely driven by convective and shear instabilities, critical level filtering, and viscous damping. Energy baselines are then used to estimate the diffusion‐like transport of constituents and heat induced by non‐breaking GWs. The corresponding wave‐induced constituent and thermal diffusivities and are compared to estimates made at other locations, while this study represents the first such observations in the middle atmosphere. Estimated and are up to 1,000 times typical eddy and molecular diffusion values in the middle atmosphere and 10 times typical values in the MLT.