Collaborative Research: Turbulence and Wave Dynamics from the Mesosphere to the Lower Thermosphere above the Andes

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This award would support the continued operations of the Na wind-temperature lidar at Andes Lidar Observatory (ALO) in Cerro Pachón, Chile (30.26S, 70.74W, elev. 2530 m) to study the mesosphere and lower thermosphere (MLT) dynamics and ion-neutral coupling processes. The lidar at ALO is a state-of-the-art Na resonance-fluorescence Doppler lidar, capable of measuring 3D wind, neutral temperature and Na density profiles at high vertical (500 m) and temporal (1 min) resolutions in the 80-105 km altitude range with high accuracy. Two key advancements of ALO lidar capabilities featuring the extension of lidar observing profile into the lower thermosphere, with wind and temperature measurements up to 140 km altitude, and the ability to detect turbulence scale perturbations in temperature and wind would enable investigations focused on scientific topics that are at the forefront of MLT science. The physical processes that define the dynamics, structure, and variability in the MLT also operate throughout the atmosphere and in all stratified and sheared geophysical fluids, e.g., oceans, lakes, other planetary atmospheres and stellar interiors. This project would provide opportunities for a postdoc researcher, graduate and undergraduate students to participate in the science, engineering and observations. The data acquired with the Na lidar at ALO will serve a broad community interested in research from the lower atmosphere to the upper thermosphere. Possible science goals that would be studied through the application of the measurements collected are: determination of turbulence fluxes and eddy diffusion coefficients of heat and momentum and the Prandtl number; investigation of the vertical transport of heat and energy caused by dissipating gravity waves at various scales,quantification of the interactions among gravity waves, tides, and planetary waves at different seasons;analysis and modeling of gravity wave evolution process through variable background atmosphere; and understanding the ion-neutral coupling processes underlying the formation of thermospheric Na layers.