Volcanic ash cloud retrieval by ground-based microwave weather radar
Volcanic ash cloud retrieval by ground-based microwave weather radar
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DOI：
10.1109/tgrs.2006.879116
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发表时间：
2006-11-01
影响因子：
8.2
通讯作者：
Rose, William I.
中科院分区：
文献类型：
--
作者：
Marzano, Frank Silvio;Barbieri, Stefano;Rose, William I.
评价了地基微波天气雷达系统用于火山灰云探测和定量反演的潜力。雷达反射率因子之间的关系，灰浓度，和下降率的统计推导出各种喷发制度和灰大小通过应用雷达反射率微物理模型。为了定量评估气象雷达对灰的识别能力，通过模拟合成灰云和作为范围函数的不同灰浓度和大小进行了灵敏度分析。雷达规格取自S、G和X波段的典型雷达系统。讨论了火山灰雷达反演的原型算法。从测量的单偏振反射率出发，反演火山灰浓度和降落速率的统计反演技术基于两个级联步骤，即：1）火山喷发状态和火山灰类别的分类和2）火山灰浓度和降落速率的估计。使用合成数据集评估VARR算法估计的预期准确度。VARR技术的应用程序，最后显示，考虑到在冰岛的格里姆火山爆发于2004年11月。体积扫描数据从多普勒C波段雷达，这是位于260公里，从火山口，通过VARR算法处理。可实现的VARR产品的例子介绍和讨论。
The potential of ground-based microwave weather radar systems for volcanic ash cloud detection and quantitative retrieval is evaluated. The relationship between radar reflectivity factor, ash concentration, and fall rate is statistically derive for various eruption regimes and ash sizes by applying a radar-reflectivity microphysical model. To quantitatively evaluate the ash delectability by weather radars, a sensitivity analysis is carried out by simulating synthetic ash clouds and varying ash concentration and size as a function of the range. Radar specifications are taken from typical radar systems at S-, G, and X-band. prototype algorithm for volcanic ash radar retrieval (VARR) is discussed. Starting from measured single-polarization reflectivity, the statistical inversion technique to retrieve ash concentration and fall rate is based on two cascade steps, namely: 1) classification of eruption regime and volcanic ash category and 2) estimation of ash concentration and fall rate. Expected accuracy of the VARR algorithm estimates is evaluated using a synthetic data set. An application of the VARR technique is finally shown, taking into consideration the eruption of the Grimsvotn volcano in Iceland on November 2004. Volume scan data from a Doppler C-band radar, which is located at 260 kin from the volcano vent, are processed by means of the VARR algorithm. Examples of the achievable VARR products are presented and discussed.