VHF radar observations of tides at polar latitudes in the summer mesosphere

Abstract

Doppler measurements at mesospheric heights were carried out in June 1984 using the mobile SOUSY VHF radar at Andenes/Norway (69°N, 16°E). The temporal wind variations at heights between 80 and 95 km reveal wave motions with periods of about 12 h, 14.5 h, 24 h and 54 h. The propagating semi-diurnal tide has amplitudes up to 20 m s −1 and a vertical wavelength of about 30 km. The diurnal tide is much weaker and the phase shows a more complex variation with height. The 14.5 h period motion reveals a maximum amplitude of 15 m s −1 at about 84 km and a vertical wavelength of 15 km.