Multi-Year Behavioral Observations of Quasi-2-Day Wave Activity in High-Latitude Mohe (52.5°N, 122.3°E) and Middle-Latitude Wuhan (30.5°N, 114.6°E) Using Meteor Radars

Abstract

The behavior of multi-year quasi-2-day wave (Q2DW) activity in the high and middle latitudes in the mesosphere and lower thermosphere regions during 2013–2022 is revealed, for the first time, using two meteor radars along the 120°E longitude, which are located at Mohe (52.5°N, 122.3°E) and Wuhan (30.5°N, 114.6°E). We first describe the interannual monthly mean characteristics of the Mohe and Wuhan winds. We then determine the extraction of the Q2DWs via a least-squares method and calculate the occurrence dates, amplitudes, periods, and phases of the zonal and meridional Q2DWs. We find that the summer zonal wind speed of Mohe reached ~35 m/s at ~94 km in 2022, and the meridional wind speed reached ~−20 m/s at ~88 km in 2017. Similarly, the zonal and meridional wind speeds in Wuhan reached ~48 m/s and ~−30 m/s at ~94 km and ~90 km, respectively, in the summer of 2020. Statistical analysis shows that, in Mohe and Wuhan, the highest frequency of Q2DWs is observed between days 200 and 220. The Q2DW is mainly associated with the background mean wind and is consistent with a selective filtering mechanism. We believe that the correlation between wind shear and Q2DW amplitude is higher in summer because wind shear reaches its maximum when Q2DW starts to amplify. The wave period of the Mohe zonal Q2DW is longer than that of the Wuhan zonal Q2DW, while that of the meridional Q2DW is shorter. In addition, the zonal and meridional Q2DW amplitudes are weaker in Mohe than in Wuhan. The vertical wavelength of the Q2DW in Wuhan is shorter than that in Mohe. Solar activity F10.7 does not appear to be strongly correlated with Q2DW behavior in Mohe and Wuhan.