Anomalous Increase in the Occurrence of Post-Midnight FAI Radar Echoes in September 2019 and Its Relation With the Austral Sudden Stratospheric Warming. - Meenakshi, S.; Sridharan, S.; Ivan, J. Solomon; Hozumi, K.; Yatini, C. Y.; Yokoyama, T.; Hashiguchi, H. (Journal of Geophysical Research. Space Physics, 2021)