## 2 Observations and Method for Data Analysis
### Climatology, Seasonal and Interannual Variability of the Nonmigrating Semidiurnal Tides
While the AM in the NH is centered around (30-40\({}^{\circ}\)) N, that in the SH is at a latitude of \(\sim\)40\({}^{\circ}\) S. Generally, the NH AC, centered at \(\sim\)40\({}^{\circ}\) N, is stronger than that in SH located around (30-40\({}^{\circ}\)) S. The SAC also shows some hemispheric asymmetry, but weaker than those of the AM and AC; while the NH SAC is centered around (20-30\({}^{\circ}\)) N, the SH SAC can be seen between 20\({}^{\circ}\) S and 40\({}^{\circ}\) S. Some interannual variability, mainly the quasi-2-year one, can be distinguished mainly in the AM and AC of SW4 and in the AM, particularly in the NH of SE2. Figure 5: **(a)** Latitude-time structures of the climatologically mean amplitudes (2002–2022) of SW4 **(left** plot, in K) and SE2 **(right** plot) at altitude of 110 km; **(b)** altitude–latitude structures of the amplitudes **(upper** row of plots, in K), and phases **(bottom row of plots, in degrees) of the above-mentioned semidiurnal tides, arranged in the same way as in **(a)**. Figure 6: _Cont._  
Figure 6: Latitude-time structures of the monthly mean SW4 (**upper** plot) and SE2 (**bottom** plot) amplitudes at altitude of 110 km. Figure 7: (**a**) Latitude-time structures of the AM (**upper** plot), AC (**middle** plot), and SAC (**bottom** plot) of the SW4 monthly mean amplitudes at altitude of 110 km; (**b**) the same as (**a**), but for the SE2. Figure 8a (left column of plots) presents the cross-correlation functions between the QBO at 30 hPa and the AM (upper plot), AC (middle plot), and SAC (bottom plot) of the SW4, while Figure 8b (right column of plots) shows the same as Figure 8a, but for SE2. We again underline that only the cross-correlation function at latitudes where the respective seasonal components have large amplitudes makes physical sense. A quite strong positive correlation of 0.5 between the QBO and the AM of SW4 (near the equator) is evident in Figure 8a (upper plot); that is, however, out of phase with the stratospheric QBO. There is also a weaker positive correlation of ~0.30 near 20\({}^{\circ}\) N that lags behind of the QBO with 9-10 months. The AC of SW4 (middle plot) at (10-20\({}^{\circ}\)) N also demonstrates strong positive correlation of 0.55 with a time delay of 8-9 months. A positive correlation of 0.40 shows the SAC of SW4 (bottom plot) at ~20\({}^{\circ}\) S, with a time delay of 6-7 months. The AM seasonal component of SE2 around (30-40\({}^{\circ}\)) N demonstrates a negative correlation of \(-\)0.50 (Figure 8b, upper plot) with a time lag of ~7 months; negative correlations also show at the AM at ~10\({}^{\circ}\) S and 40\({}^{\circ}\) S, with a shorter time lag of ~2-4 months. The AC of SE2 (middle plot) is strong at (30-40\({}^{\circ}\)) N, but there is a negative maximum of only \(-\)0.30 around 30\({}^{\circ}\) N that is out of phase with the QBO. The AC of SE2 in the SH is significantly weaker than that in the NH; however, it reveals a positive correlation of ~0.30 around (30-40\({}^{\circ}\)) N that also is out of phase with the QBO. The SAC of SE2 (bottom plot) at latitude of ~20\({}^{\circ}\) N reveals a weak positive correlation of ~0.25 and out of phase dependence with the stratospheric QBO; there is stronger correlation of 0.35 of the SAC at around 10\({}^{\circ}\) S, but there this component is not large. Figure 8: **(a, left column of plots)** Crosscorrelation functions between the QBO and the AM (**upper** plot), AC (**middle** plot), and SAC (**bottom** plot) of the SW4; and (**b, right** column of plots) the same as (**a**), but for the SE2. Summarizing the interannual variability of the SW4 and SE2 seasonal components, we may conclude that, similarly to the considered diurnal nonmigrating tides, here, also, it demonstrates well-visible QBO variability in the lower thermosphere. In general, the QBO impact is weaker than that on the considered diurnal nonmigrating tides.