The Arctic MLT wind regime parameters measured at the ground-based network of MF and meteor radar stations (Andenes 69° N, Tromsø 70° N, Esrange 68° N, Dixon 73.5° N, Poker Flat 65° N and Resolute Bay 75° N) are discussed and compared with those observed in the mid-latitudes. The network of the ground-based MF and meteor radars for measuring winds in the Arctic upper mesosphere and lower thermosphere provides an excellent opportunity for study of the main global dynamical structures in this height region and their dependence from longitude. Preliminary estimates of the differences between the measured winds and tides from the different radar types, situated 125-273km apart (Tromsø, Andenes and Esrange), are provided. Despite some differences arising from using different types of radars it is possible to study the dynamical wind structures. It is revealed that most of the observed dynamical structures are persistent from year to year, thus permitting the analysis of the Arctic MLT dynamics in a climatological sense. The seasonal behaviour of the zonally averaged wind parameters is, to some extent, similar to that observed at the moderate latitudes. However, the strength of the winds (except the prevailing meridional wind and the diurnal tide amplitudes) in the Arctic MLT region is, in general, less than that detected at the moderate latitudes, decreasing toward the pole. There are also some features in the vertical structure and seasonal variations of the Arctic MLT winds which are different from the expectations of the well-known empirical wind models CIRA-86 and HWM-93. The tidal phases show a very definite longitudinal dependence that permits the determination of the corresponding zonal wave numbers. It is shown that the migrating tides play an important role in the dynamics of the Arctic MLT region. However, there are clear indications with the presence in some months of non-migrating tidal modes of significant appreciable amplitude.
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机译：北极MLT风态参数是在中频和流星雷达站的地面网络上测得的（Andenes 69°N，Tromsø70°N，Esrange 68°N，Dixon 73.5°N，Poker Flat 65°N和Resolute Bay 75° N）进行了讨论，并与中纬度地区的观测结果进行了比较。用于测量北极上部中层和下部热层中风的地面中频和流星雷达网络为研究该高空区域的主要全球动力结构及其对经度的依赖性提供了极好的机会。提供了对距离相距125-273公里（特罗姆瑟，安德内斯和埃斯兰奇）的不同雷达类型测得的风潮和潮汐之差的初步估计。尽管使用不同类型的雷达会产生一些差异，但仍可以研究动态风结构。结果表明，大多数观测到的动力学结构每年都保持不变，因此可以从气候学角度分析北极MLT动力学。纬向平均风参数的季节性行为在某种程度上类似于中纬度地区的观测。但是，北极MLT区域的风强度（主要的子午风和日潮幅值除外）通常小于在中等纬度处检测到的强度，并向极点减小。北极MLT风的垂直结构和季节性变化也有一些特征，这与著名的经验风模型CIRA-86和HWM-93的期望不同。潮汐相显示出非常明确的纵向依赖性，可以确定相应的纬向波数。结果表明，迁徙潮汐在北极MLT地区的动力学中起着重要作用。但是，有明显迹象表明，几个月来存在明显幅度明显的非迁移潮汐模式。
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