In this study, we report the climatology of migrating and non-migrating tides in mesopause winds estimated using multiyear observations from three meteor radars in the southern equatorial region. The results reveal that the climatological patterns of tidal amplitudes by meteor radars is similar to the Climatological Tidal Model of the Thermosphere (CTMT) results and the differences are mainly due to the effect of the stratospheric sudden warming (SSW) event.

Characteristics of static stability (N²) in the tropical tropopause are analyzed using 0.1 km vertical resolution temperature profiles retrieved from COSMIC GNSS-RO. We define the tropopause inversion layer (TIL) by the sharp increase in N² across the cold point tropopause (CPT) and the thickness of the enhanced peak in N² just above the CPT. We investigated the TIL at the intraseasonal to interannual timescales above the Maritime Continent and Pacific Ocean with different land–sea distribution.

Results of comparisons between data collected from a VHF Doppler radar and small unmanned aerial vehicles (UAVs) are presented. The UAVs, equipped with meteorological sensors, flew nearby the radar up to an altitude of ~ 4.0 km. Both instruments detected the same clear-air refractive index gradients at a vertical scale of ~ 20 m when the vertical stratification was strong. A VHF radar can thus provide a faithful image of the vertical stratification of the atmosphere down to decimeter scales.

We investigated the zonal and meridional momentum flux at 86–94 km using two nearly identical sets of meteor radar observation data at Koto Tabang and Biak in Indonesia (both at the Equator) by applying a method proposed by Hocking (2005). The observed zonal momentum flux at the two sites agreed reasonably well at 86, 90, and 94 km during the observation periods when the data acquisition rate was large enough. Our results suggest the usefulness of the Hocking method.