The PROUST radar: First results

Two campaigns took place in 1984 with the PROUST Radar operating in a bistatic mode, the transmitting antenna pointing at the vertical and the receiving one, 1 deg. off the vertical axis. The antenna beam intersection covers an altitude range between 3 and 9 km. The first of these campaigns are analyzed. The results analyzed show the capability of the PROUST Radar to measure the turbulent parameters and study the turbulence-wave interaction. In its present configuration (bistatic mode and 600 m vertical resolution), it has been necessary to make some assumptions that are known not to be truly fulfilled: homogeneous turbulence and constant vertical wind intensity over a 600-m thickness. It is clear that a more detailed study of the interaction between wave and turbulence will be possible with the next version of PROUST Radar (30-m altitude resolution and monostatic mode) that will soon be achieved

VHF radar observations of the dynamics of the summer polar mesopause region

Observations of the dynamics of the mesopause region over the Norwegian island of Andøya (69°N, 16°E) made during 2 days in summer 1987 using the mobile SOUSY VHF (53.5 MHz) Doppler Radar are reported. Measurements of the three mean wind components and the 12- and 24-hour horizontal tidal components, as well as preliminary estimates of the component of the total upward flux of density-normalized horizontal momentum in the SW–NE plane and the anisotropy of the horizontal wind are presented for the 83- to 90-km height interval. Values of the component of the density-normalized flux in the SW–NE plane for the 10-min to 48-hour period range, after the 12-and-24-hour tidal components have been removed, vary from −1 m2 s−2 near 84 km to 16 m2 s−2 near 89 km. The major contribution is from the 10-min to 12-hour period range. The corresponding mean flow acceleration takes a mean value of −136 m s−1 d−1over the 83–90 km height interval. The anisotropy is considerable and may suggest the presence of standing waves.Rüdiger Rüster and Iain M. Rei