The radar volume reflectivity and turbulent kinetic energy dissipation rate in the Antarctic mesosphere were estimated from the polar mesosphere winter echoes (PMWE) recorded using a vertical beam of the PANSY radar, a Mesosphere‐Stratosphere‐Troposphere radar at Syowa Station (69°S, 40°E), over a period of 4 years. The observed radar volume reflectivity exhibits a lognormal distribution in the range of 2 × 10⁻¹⁸ to 5 × 10⁻¹⁵ m⁻¹ for a height region of 55–82 km. The turbulent energy dissipation rate estimated from the spectral widths of the PMWE ranges from 10⁻⁴ to 10⁰ m² s⁻³. From monthly histograms of the turbulent energy dissipation rate for a fixed solar zenith angle (SZA) and height, it was found that the summer‐to‐winter transition of the turbulent energy dissipation rate occurs in March, while the winter‐to‐summer transition occurs in September. This seasonal variation agrees well with that of gravity wave activity, suggesting that the turbulence in the mesosphere is likely caused by gravity wave breaking.

中文翻译：

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根据南极PMWE谱宽估算的能量耗散率的统计分析

南极中层的雷达体积反射率和湍流动能耗散率是通过使用PANSY雷达的垂直束记录的极地中层冬季回波（PMWE）估算的，该回波是在Syowa站的中层-平流层-对流层雷达（69°S， 40°E），持续4年。在55-82 km的高度范围内，观测到的雷达体积反射率在2×10 ^-18至5×10 ^-15  m ^-1的对数正态分布。根据PMWE的光谱宽度估算的湍流能量耗散率范围为10 ^-4到10 ⁰  m ²  s ^-3。根据固定的太阳天顶角（SZA）和高度的湍流能量耗散率的每月直方图，发现湍流能量耗散率的夏季到冬季过渡发生在3月，而冬季到夏季过渡发生发生在九月。这种季节性变化与重力波活动的变化非常吻合，这表明中层湍流很可能是由重力波破裂引起的。