Response of planetary waves and tides to the 2019 Southern Hemisphere
SSW and Q2DW enhancement in Jan-Feb 2020 observed by CONDOR meteor radar
in Chile and Adelaide meteor radar in Australia
Abstract
A new multi-static meteor radar (CONDOR) has recently been installed in
northern Chile. This CONDOR meteor radar (30.3°S, 70.7°W) and the
Adelaide meteor radar (35°S, 138°E) have provided longitudinally spaced
observations of the mean winds, tides and planetary waves of the
PW-tides interaction cases we present here. We have observed a
Quasi-6-Day Wave (Q6DW) enhancement in MLT winds at the middle latitudes
(30.3°S, 35°S) during the unusual minor South Hemisphere SSW 2019 by the
ground-based meteor radars. Tidal analysis also indicates modulation of
the Q6DW w/ amplitude ~15 [m/s] and diurnal tides w/
amplitude ~60 [m/s]. Another case we present here is
a dominant Quasi-2-Day Wave (Q2DW) with up to 50 [km/s] amplitude
occurring in SH summer 2020 and its interaction with the diurnal and
semidiurnal tides. The period of this Q2DW activity changes from
~50hr to ~48hr since Jan 19, which
suggests the phase locking mechanism [McCormack et al., 2010]. The
24hr-feature and 12hr-feature show off-phase variations during the Q2DW
enhancement time with amplitude of ~40 [m/s].