A dual‐beamwidth radar method for measuring atmospheric turbulent kinetic energy
A dual‐beamwidth radar method for measuring atmospheric turbulent kinetic energy
复制标题
大气湍流动能双波束宽度雷达测量方法
DOI：
10.1029/2001gl014283
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发表时间：
2002
影响因子：
5.2
通讯作者：
W. Clark
中科院分区：
文献类型：
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作者：
T. Vanzandt;G. Nastrom;J. Furumoto;T. Tsuda;W. Clark
本文介绍了一种新的双波束宽度(2BW)雷达推算单位质量湍动能密度引起的σ涡流速度变化的方法。与标准单波束宽度(1BW)方法相比，2BW方法具有对观测速度方差σOBS2进行必要的仪器改正的敏感性低得多的优点。我们使用σOBS2在日本茂名附近的MU甚高频雷达上测量了5.0kmMSL和7.5kmMSL，波束指向10°天顶角，对2BW和1BW方法进行了测试和比较。我们发现，在微风期间，两种方法得到的σ涡轮机2廓线吻合得很好。但在风速为>；30m/S的情况下，σ涡轮机2的1BW值比2BW值大约25%。采用2BW方法后，6~7.5 kmMSL6.0~7.5kmMSL6.0~7.5kmMSL6.0~7.5kmMSL范围内σ涡度的典型值由∼0.07m~2/s2(风速2 m/S)增加到∼0.2m2/s2(风速30~60m/S)。
This paper introduces a new dual‐beamwidth (2BW) radar method for inferring the velocity variance σturb2 due to the turbulent kinetic energy density per unit mass. The 2BW method has the advantage of being much less sensitive than the standard single‐beamwidth (1BW) method to the necessary instrumental corrections of the observed velocity variance σobs2. We test and compare the 2BW and 1BW methods using σobs2 between 5.0 and 7.5 km MSL measured by the MU VHF radar near Shigaraki, Japan, with beams directed toward 10° zenith angle. We find that during periods of light winds the σturb2 profiles from the two methods agree well. But with wind speeds >30 m/s the 1BW values of σturb2 are about 25% larger than the 2BW values. With the 2BW method, typical values of σturb2 between 6.0 and 7.5 km MSL increased from ∼0.07 m2/s2 with winds of ∼2 m/s to ∼0.2 m2/s2 with winds between 30 and 60 m/s.