Polarimetric Radar Signatures of Dendritic Growth Zones within Colorado Winter Storms
Polarimetric Radar Signatures of Dendritic Growth Zones within Colorado Winter Storms
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科罗拉多冬季风暴中树突生长区的偏振雷达特征
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
Yinghui Lu
中科院分区：
文献类型：
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作者：
R. Schrom;M. Kumjian;Yinghui Lu
对2013年2月20-21日、3月9日和4月9日美国科罗拉多州东北部冬季风暴的x波段偏振雷达观测资料进行了分析。这些观测结果是由科罗拉多州立大学-芝加哥大学-伊利诺伊州水调查（CSU-CHILL）雷达在前线地形风暴（FROST）项目期间拍摄的。在有利于枝晶冰晶生长的- 15°C温度水平附近，水平极化反射率因子ZH、微分反射率ZDR和特定差相KDP的极化雷达矩在不同时间表现出一系列特征。总的来说，这些区域的KDP增强，ZDR向地面减小，ZH向地面增大，提示聚集（或轮动）。最大的ZDR值（~3.5 ~ 5.5 dB）出现在低空上坡流显著的时期。当上坡气流较弱时，对流特征的KDP（>1.5°km−1）和ZH （>20 dBZ）值最高。电磁散射计算…
AbstractX-band polarimetric radar observations of winter storms in northeastern Colorado on 20–21 February, 9 March, and 9 April 2013 are examined. These observations were taken by the Colorado State University–University of Chicago–Illinois State Water Survey (CSU-CHILL) radar during the Front Range Orographic Storms (FROST) project. The polarimetric radar moments of reflectivity factor at horizontal polarization ZH, differential reflectivity ZDR, and specific differential phase KDP exhibited a range of signatures at different times near the −15°C temperature level favored for dendritic ice crystal growth. In general, KDP was enhanced in these regions with ZDR decreasing and ZH increasing toward the ground, suggestive of aggregation (or riming). The largest ZDR values (~3.5–5.5 dB) were observed during periods of significant low-level upslope flow. Convective features observed when the upslope flow was weaker had the highest KDP (>1.5° km−1) and ZH (>20 dBZ) values. Electromagnetic scattering calculation...