Fig. 4From: Extraordinary quasi-16-day wave activity from October 2013 to January 2014 with radar observations at mid-latitudes and MERRA2 reanalysis dataWavelet spectra of a, c zonal and b, d meridional winds at 88Â km between 1 September 2013 and 1 April 2014 from meteor radar observations over a, b Beijing and c, d Wuhan. The black dashed and dotted vertical lines denote the minor SSW and SFW events, respectively. The tilted solid lines denote the cone of influence for the wavelet analysisBack to article page