6 year mean prevailing winds and tides measured by VHF meteor radar over Collm (51.3°N, 13.0°E)

The Collm (51.3 degrees N, 13.0 degrees E) meteor radar has been operated continuously since summer 2004. 6-year means of horizontal prevailing winds and tides at 80-100 km height are shown. Qualitatively, the results confirm known circulation features, but some peculiarities are found. Mean winds are stronger than those that has been predicted by radar based empirical models, but, with respect to the order of magnitude, they agree well with the Horizontal Wind Model (Drob et al., 2008). Meridional mean winds are closely connected and linearly correlated with the mean zonal wind shear. Tidal amplitudes are stronger than those that have been frequently measured by earlier measurements. The semidiurnal tidal amplitudes exceed 60 m/s at 97 km altitude. The semidiurnal tide has maximum amplitudes during winter and another maximum in September, but in addition near the mesopause a tertiary maximum is found in spring. The terdiurnal amplitudes are stronger than those that are previously reported. (C) 2011 Elsevier Ltd. All rights reserved.