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​This MRI award would acquire a state-of-the-art meteor radar (MR) system that would replace an aging meteor radar located at the Andes Lidar Observatory (ALO), located in Cerro Pachon, Chile (30.26 S, 70.74 W, elev. 2530 m). This clear sky location is ideally situated for making observations of the highly dynamical environment associated with the mountain waves generated by the surface winds blowing over the Andes. This location is also well suited for detecting sodium particles transported to high altitude by the Appleton fountain effect that operates near the geomagnetic equator. Both of these mechanisms make the Andes dynamical environment a "hot spot" that is unique in the world with nothing equivalent available for study in the United States. ALO is an upper atmosphere observatory that supports optical remote sensing instruments, including a wind/temperature (W&T) lidar operating at the sodium wavelength (589 nm) and several airglow instruments. The lidar system measures simultaneously nighttime atmospheric wave perturbations (associated with gravity waves) of temperature, wind and airglow intensities in the mesosphere and lower thermosphere (MLT) region (80-105 km) at high vertical spatial (<1 km) and temporal resolutions (~1 min) during the low moon period of each month. The MR data provides measurements of the background tidal winds that allow the determination of the intrinsic phase speeds needed for studying gravity wave propagation physics. These results taken together are aimed at achieving a detailed study of atmospheric waves and turbulence structures through modeling comparisons of data with turbulent structure morphology. This project will support engineering undergraduate students at ERAU thus helping to extend the STEM undergraduate education effort at ERAU into the remote sensing area. One graduate and one undergraduate student would be directly involved in this project. Moreover, these applications made possible by the enhanced quality of the MR data would provide new opportunities for graduate student training in the radar remote sensing technology as well as having these students undertake studies regarding new questions in upper atmosphere research. Students involved will learn the principles of the MR remote sensing technique through the use of formal lectures and informal hands-on interactions. Activities involving the graduate student are site radar noise survey, the process of radar installation and subsequent hardware maintenance. The student would also be responsible for data retrieval, validation and archival processing. The undergraduate student would help set up the Madrigal server and update the ERAU website concerning the meteor radar status. These activities will provide training to these students on how to become an experimental scientist. The MR would also support undergraduate and graduate education at ERAU as the department offers an undergraduate course in Space Physics, one MS level course Experimental Methods in Space Science, and two PhD level courses Upper Atmosphere Physics and Remote Sensing: Active and Passive. Students will learn advanced techniques involved in MR and use the MR data for various course projects. Students can design their own software for meteor identification, wind and temperature retrieval. 

The MR measures horizontal wind continuously (day and night) in the same altitude region as the height range observed by the lidar with ~2 km vertical and 1 hr resolutions. It complements the optical lidar measurements by providing background tidal wind information that is critical for deriving gravity wave (GW) intrinsic parameters and understanding the phenomenology of GW wave propagation with regard to reflection, ducting, and dissipation processes. The MR capability for continuous wind measurement is essential for resolving longer time scale oscillations such as atmospheric tides and planetary waves, and for the study of their interactions with small-scale waves. The new MR will not only continue the MR wind measurement series but also provides new capabilities to infer temperature, turbulence diffusion coefficient, and the diurnal variation of GW momentum flux.