Effects of planetary wave oscillation on E-sporadic (Es) layers during the rare Antarctic sudden stratospheric warming of 2019

• The rare Sep 2019 Antarctic SSW affected Es layers across the Americas, Oceania , and Asia . • PW dynamics were disrupted during the SSW, with tide-PW nonlinear interactions potentially enhancing Es layer formation and high ftEs values. • Wavelet analysis of ftEs/tidal winds revealed PWs with quasi-2, -4, -6, and -8-day periodicities. This study investigates the impact of the rare 2019 Antarctic Sudden Stratospheric Warming (SSW) event on the top frequency parameter ( ftEs ) of the sporadic E ( Es ) layers, using data from several ionosondes located at low and mid-latitudes across the Southern and Northern Hemispheres, including stations in the American, Oceanian, and Asian regions. The ionosonde data were also used to identify frequency anomalies in the Es layers during the event. Additionally, data from three meteor radars in South America were used to further analyze the impact of the SSW, focusing on key parameters such as tidal winds and Planetary Wave (PW) oscillations. The study found significant ftEs peaks exceeding 10 MHz, particularly at low-latitude stations, with values reaching up to 20 MHz. The presence of these atypical peaks in ftEs was related to PW activity, which intensified the electron densities in the Es layers. A wavelet analysis of the ftEs and neutral wind data revealed oscillations associated with PW and tidal interactions, with dominant periods of ∼2–8-days. These patterns were more pronounced in the Southern Hemisphere, indicating stronger PW-tide coupling compared to the Northern Hemisphere. In addition, this study shows that the non-linear interaction between the PW and the tides occurred globally, generating secondary oscillations of ∼2–8-days on the Es layer development for the three continents. These oscillations were observed in the zonal (U) and meridional (V) winds of the diurnal and semidiurnal tides (DT and ST) during the SSW event, demonstrating a coupling in the troposphere-stratosphere-lower atmosphere dynamics. The coupling between the stratosphere and lower thermosphere contributed to the observed anomalies, revealing the broader impacts of SSW events on Es layer behavior. This study provides an understanding of the impact of SSW on Es layers, using ionosonde data and wave oscillation analysis that could enhance data assimilation models for more accurate ionospheric prediction.