Na Doppler/temperature lidar: Initial mesopause region observations and comparison with the Urbana medium frequency radar
Na Doppler/temperature lidar: Initial mesopause region observations and comparison with the Urbana medium frequency radar
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Na 多普勒/温度激光雷达：初始中层顶区域观测以及与厄巴纳中频雷达的比较
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发表时间：
1991
期刊：
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通讯作者：
S. Franke
中科院分区：
文献类型：
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作者：
Richard E. Bills;C. Gardner;S. Franke
高层大气中的流星烧蚀是大约80至105公里高度之间的致密钠原子层的来源。峰值密度通常为几千个原子/立方厘米，总丰度在中纬度地区随季节变化，冬季最大。钠层是这一区域大气的热结构和密度结构的敏感示踪剂，可以使用共振荧光激光雷达技术进行探测，具有非常高的精度和分辨率。我们报告的垂直分辨钠密度，温度，风廓线在中层顶区域使用一个新的四频多普勒/温度激光雷达的第一次观测。初始纬向风和温度观测的分辨率为30 min和1.5 km，均方根精度为12 m/s和2 K。这些测量是在1991年3月14-15日夜间与厄巴纳大气观测站（40°N，88°W）的中频（MF）雷达同时进行的。在95.5km处的平均温度廓线显示出一个温度为181 K的中层顶。平均纬向风廓线在97公里处有一个58米/秒的强向西急流，这似乎与中层顶有关。在6小时45分钟的观测期间，Na多普勒风，平均在88和98公里之间，表现出相同的总体趋势，在同一地区的MF雷达视风和真风。然而，激光雷达和雷达速度估计值在夜间的某些时候相差高达40米/秒。
Meteoric ablation in the upper atmosphere is the source of a dense layer of atomic Na between about 80 and 105 km altitude. Peak densities are typically several thousand atoms/cm3, and the total abundance varies seasonally at mid-latitudes with the maximum in winter. The Na layer is a sensitive tracer of the thermal and density structure of this region of the atmosphere and can be probed with exceptional accuracy and resolution using resonance fluorescence lidar techniques. We report the first observations of vertically resolved Na density, temperature, and wind profiles in the mesopause region using a new four-frequency Doppler/temperature lidar. The initial zonal wind and temperature observations were obtained with a resolution of 30 min and 1.5 km and rms accuracies of 12 m/s and 2 K. These measurements were conducted simultaneously with the medium frequency (MF) radar at the Urbana Atmospheric Observatory (40°N, 88°W) during the night of March 14–15, 1991. The mean temperature profile exhibits a well-defined mesopause at 95.5 km with a temperature of 181 K. The mean zonal wind profile exhibits a strong 58 m/s westward jet at 97 km which appears to be related to the mesopause. During the 6-hour and 45-min observation period the Na Doppler winds, averaged between 88 and 98 km, exhibit the same general trends as the MF radar apparent and true winds in this same region. However, the lidar and radar velocity estimates differ by as much as 40 m/s at some times during the night.