Atmospheric Gravity Waves from a Special Campaign during Austral Winter 2021 using the Aeolus Doppler Wind Lidar

ESA's Aeolus satellite is the first Doppler wind lidar in space. Due to its global coverage of high resolution wind observations from near the surface to the tropopause and UTLS, Aeolus provides a unique opportunity to study gravity waves (GWs) in a completely new way. Current space-based measurements of GWs are spatially limited in this altitude range and, even where available, cannot measure GW perturbations in wind. Previous research demonstrates that Aeolus has the ability to measure GWs, and so this and future Doppler wind lidar satellites have the potential to transform our understanding of such critically-important dynamical processes. In this study, we use observations from a special Aeolus scanning mode to study orographic GWs over the Southern Andes during winter 2021. The changes made to the satellite's range-bin settings allows observations of GW wind structures higher into the stratosphere than before, and enables detailed measurements of the vertical and horizontal wavelength. We also sample ERA5 as Aeolus to produce like-for-like comparisons of resolved and observed GW structures, which shows differences in the morphology of these waves. More generally, our research highlights how Aeolus and future Doppler wind lidar satellites can deepen our understanding of the propagation of GWs in the UTLS.