Empirical model of the dynamics in the mesosphere and lower thermosphere region over the UK, including solar and geomagnetic activity

A new single-station empirical model of the dynamics of the mesosphere/lower thermosphere (MLT) region has been developed. The data for the model were recorded with a meteor radar located in the UK. The model uses hourly data in a “representative day” for each month, where the representative day for each month is obtained by a superposed epoch analysis. The F10.7 solar radio flux and the planetary geomagnetic Ap-index are included as external parameters. The monthly representative-day winds recorded over the UK near 52∘N, 2∘W in the interval January 1988-December 2000 have been used to construct the model. The accuracy of the model is discussed in terms of standard deviation and systematic error. In general, the model describes the zonal wind component more accurately than the meridional component. To assess the contribution of solar and geomagnetic influences, a quantitative comparison is made with a wind model in which these influences were not taken into account. The results show a noticeable contribution to the dynamics of the MLT region from changes in the solar/geomagnetic factors. The major contribution of the solar/geomagnetic influences is found to be evident in the variability of the 12-h tide. The solar/geomagnetic influences are more noticeable in the meridional wind component. The results also indicate tides of 8- and 6-h period, often considered to be insignificant, are present in the MLT region.