Mean winds, tides, and quasi-2 day wave in the polar lower thermosphere observed in European Incoherent Scatter (EISCAT) 8 day
Mean winds, tides, and quasi-2 day wave in the polar lower thermosphere observed in European Incoherent Scatter (EISCAT) 8 day
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欧洲非相干散射 (EISCAT) 8 天观测到的极地低层热层的平均风、潮汐和准 2 天波
DOI：
10.1029/2005ja011128
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发表时间：
2005
影响因子：
--
通讯作者：
R. Fujii
中科院分区：
文献类型：
--
作者：
S. Nozawa;A. Brekke;S. Maeda;T. Aso;C. Hall;Y. Ogawa;S. Buchert;J. Röttger;A. Richmond;R. Roble;R. Fujii
[1] 2003年11月11日至19日，利用特罗姆瑟（69.6°N, 19.2°E）超高频雷达和斯瓦尔巴德（朗伊尔城，78.2°N, 16.0°E）两台EISCAT雷达连续8天同时进行了欧洲非相干散射（EISCAT）雷达观测，研究了极地地区低层热层风动力学。在特罗姆瑟和朗伊尔城，日晷分量和半日晷分量的高度分布是相似的。经向和纬向分量的半日振幅在105 ~ 107 km处最大，值为~ 70 ~ 90 m s−1。半日相的垂直波长在98到110公里之间，大约有30公里的变化。准2日波（Q2DW）在特罗姆瑟和朗伊尔城的低层热层均未探测到，而在特罗姆瑟中频雷达定位的中层70 ~ 82 km处发现了准2日波。这一观测结果表明，冬季Q2DW一般在中间层减弱，不能穿透到低层热层。在特罗姆瑟的107公里以下和朗伊尔城的118公里以下，风的离子阻力加速度通常可以忽略不计，但在这些高度以上发现了显著的离子阻力加速度。对这一时期的平均风和潮汐振幅和相位与国家大气研究中心热层-电离层-中间层-电动力学环流模式预测结果的比较显示出一些一致。
[1] Simultaneous European Incoherent Scatter (EISCAT) radar observations using two EISCAT radars, the Tromso (69.6°N, 19.2°E) UHF radar and the EISCAT Svalbard radar (Longyearbyen, 78.2°N, 16.0°E), were conducted for 8 consecutive days, from 11 to 19 November 2003, to study the lower thermospheric wind dynamics in the polar region. Altitude profiles of the amplitudes of the diurnal and semidiurnal components at Tromso and Longyearbyen are similar. The semidiurnal amplitudes in the meridional and zonal components exhibit maxima at 105–107 km, with values of ∼70–90 m s−1. The semidiurnal phases vary with roughly a 30 km vertical wavelength between 98 and 110 km. The quasi-2 day wave (Q2DW) was not detected in the lower thermosphere at either Tromso or Longyearbyen during the period, while it was found between 70 and 82 km in the mesosphere with the colocated Tromso MF radar. This observational result suggests that in general, the Q2DW attenuates in the mesosphere and cannot penetrate into the lower thermosphere in winter. Ion drag acceleration of the wind is generally negligible below 107 km at Tromso and below 118 km at Longyearbyen, but significant ion drag acceleration is found above these heights. A comparison of mean wind and tidal amplitudes and phases with National Center for Atmospheric Research Thermosphere-Ionosphere-Mesosphere-Electrodynamics General Circulation Model predictions for the period shows some agreement.