Variability of middle atmospheric polar ozone and its effects on Arctic mesospheric tides

We perform continuous ozone measurements above Ny-Ålesund, Svalbard (79◦ N, 12◦ E) with ground-based microwave radiometers GROMOS-C to explore the short-term and interannual variability of ozone in the polar middle atmosphere covering from 2015 to 2023. GROMOS-C measurements exhibit good agreement with MERRA-2 reanalysis and Aura-MLS satellite data. This work focuses on understanding the influence of highly altered dynamics of sudden stratospheric warming events on ozone variations in the Arctic middle atmosphere and investigating the potential role of ozone in connection to mesospheric tides reported for such events. We extract the mesospheric semi-diurnal tides (SDT) and diurnal tides (DT) from the zonal and meridional winds recorded by nearby meteor radars located at Svalbard (79◦N, 12◦E) and Tromsoe (69◦N,18.5◦E), and Sodankyla (67◦N, 26◦E) in the Arctic regions. Furthermore, these tidal observations are compared with simulations by the specified dynamics–whole atmosphere community climate model with ionosphere/thermosphere extension (SD-WACCM-X). Utilizing the middle atmospheric ozone observations by GROMOS-C and MLS, we investigate the impact of ozone variability attributed to sudden stratospheric warming events on tides in the Mesosphere and Lower Thermosphere (MLT). Our findings suggest a possible connection between alterations in middle atmospheric ozone and the underlying circulation, which subsequently influences tidal propagation up to the mesosphere. This indicates that, in conjunction with radiative forcing, these dynamics may play a significant role in driving mesospheric tides.