Mean winds of the mesosphere and lower thermosphere at 52N in the period 1988–2000
نویسندگان
چکیده
A meteor radar in the UK (near 52 N) has been used to measure the mean winds of the mesosphere/lowerthermosphere (MLT) region over the period 1988–2000. The seasonal course and interannual variability is characterised and comparisons are made with a number of models. Annual mean wind trends were found to be +0.37 ms−1 yr−1 for the zonal component and +0.157 ms−1 yr−1 for the meridional component. Seasonal means revealed significant trends in the case of meridional winds in spring (+0.38 ms−1 yr−1) and autumn (+0.29 ms−1 yr−1), and zonal winds in summer (+0.48 ms−1 yr−1) and autumn (+0.38 ms−1 yr−1). Significant correlation coefficients, R, between the sunspot number and seasonal mean wind are found in four instances. In the case of the summer zonal winds, R = +0.732; for the winter meridional winds, R = −0.677; for the winter zonal winds, R = −0.472; and for the autumn zonal winds R = +0.508.
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