Polar ozone anomalies, radiative effects, and their connection to mesospheric tidal dynamics during extreme events

Continuous ozone measurements above Ny-Ålesund, Svalbard (79°N, 12°E), using the ground-based microwave radiometer GROMOS-C, effectively capture the daily, seasonal, and interannual variability of polar ozone in the middle atmosphere. In this study, we analyze observed ozone changes during sudden stratospheric warming (SSW) events and compare the measurements with Aura/MLS satellite data and WACCM-X simulations. Results reveal the formation of a double-ozone layer in the stratosphere and lower mesosphere following the onset of SSW events, with ozone levels increasing by approximately 50% relative to the background value. Ozone absorbs solar UV radiation, contributing to radiative heating in the stratosphere and mesosphere. To further explore the impact of radiative ozone processes on mesospheric tide variability during SSWs, we extract diurnal (DT), semidiurnal (SDT), and terdiurnal (TDT) tidal components from zonal and meridional wind measurements recorded by meteor radars at three high-latitude stations: Sodankylä (67.37°N, 26.63°E), Tromsø (69.58°N, 19.22°E), and Svalbard (78.99°N, 15.99°E). The analysis reveals connections between tidal amplitude anomalies and radiative effects of ozone in the polar regions during SSW events. Additionally, we investigate the response of polar ozone to the May 2024 superstorm using Aura/MLS measurements and MERRA-2 reanalysis data. The results highlight a rapid and significant stratospheric ozone response following the superstorm and provide quantitative insights into the impact of such extreme events on ozone variability and UV radiation. This study underscores the critical role of ozone radiative processes in polar atmospheric dynamics and their modulation by extreme events, including SSWs and solar storms.