Using multi-static meteor radar networks to study the MLT over the Andes mountain range: What have we learnt so far?

In this study, we present key findings from investigations of the mesosphere and lower thermosphere (MLT) using measurements from four multi-static specular meteor radar networks located along the Andes mountain range: SIMONe Piura (5°S), SIMONe Jicamarca (12°S), CONDOR (30°S) and SIMONe Argentina (49°S). The study is mainly focused on mesoscale dynamics: from conventional estimates, such as vertical momentum fluxes, horizontal divergence, and relative vorticity, to state-of-the-art wind field reconstructions using Physics-Informed Neural Networks (PINNs). Additionally, the transverse and longitudinal correlation functions of the wind residuals have been investigated. Among others, our results show that: 1) at low latitudes, the direction of the zonal gravity wave drag coincides with the zonal background wind; 2) the contribution of large-amplitude gravity waves is similar between locations separated by thousands of kilometres. 3) In the summer mesopause region over SIMONe Argentina, the energy contributions from the wind’s rotational and divergent components are equipartitioned at high frequencies. In addition, it is expected that conventional estimates serve as valuable tools for identifying phenomena like mountain waves, which can then be analysed in greater detail using PINN-based methods such as HYPER (Hydrodynamic Point‐wise Environment Reconstructor).