Are Storm Characteristics the Same When Viewed Using Merged Surface Radars or a Merged Satellite Product?
Are Storm Characteristics the Same When Viewed Using Merged Surface Radars or a Merged Satellite Product?
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DOI：
10.1175/jhm-d-20-0187.1
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发表时间：
2020-11
影响因子：
3.8
通讯作者：
Hooman Ayat;J. Evans;S. Sherwood;A. Behrangi
中科院分区：
文献类型：
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作者：
Hooman Ayat;J. Evans;S. Sherwood;A. Behrangi
高分辨率数据集提供了改善我们对空间和时间降水模式和风暴结构的理解的潜力。这项研究的目的是评估使用天基或陆基传感器观测到的基于对象的风暴特征的相似性和差异性。基于对象的诊断评估(MODE)时间域(MTD)方法用于识别和跟踪两个高分辨率合并数据集中的风暴目标：全球降水测量(IMERG)综合多卫星反演(IMERG)最终产品V06B和基于地面雷达的多雷达定量降水估算(MRMS)。与登陆飓风有关的特征也作为一种单独的风暴类别进行了审查。结果表明，IMERG和MRM在许多基于对象的风暴特征上具有相当好的一致性。然而，有一些差异在统计上是显著的。MRMS风暴更集中，面积更小，峰值强度更高，这意味着与风暴相关的更高的山洪风险。另一方面，IMERG风暴可以在降雨量较大的情况下移动更远的距离，这意味着发生河流洪水的风险更高。就平均强度而言，移动更快的飓风的数据集之间的一致性更高。最后，MRMS表明飓风一生中的平均降水强度更高。然而，在非飓风中，观察到了相反的结果。这可能与以下因素有关：MRM的分辨率更高；从多个视角监测飓风，导致信号饱和特性与IMERG不同；和/或在较低海拔，液滴聚集效应优于蒸发效应。
High-resolution datasets offer the potential to improve our understanding of spatial and temporal precipitation patterns and storm structures. The goal of this study is to evaluate the similarities and differences of object-based storm characteristics as observed using space- or land-based sensors. The Method of Object-based Diagnostic Evaluation (MODE) Time Domain (MTD) is used to identify and track storm objects in two high-resolution merged datasets: the Integrated Multisatellite Retrievals for Global Precipitation Measurement (IMERG) final product V06B and gauge-corrected ground-radar-based Multi-Radar Multi-Sensor (MRMS) quantitative precipitation estimations. Characteristics associated with landfalling hurricanes were also examined as a separate category of storm. The results reveal that IMERG and MRMS agree reasonably well across many object-based storm characteristics. However, there are some discrepancies that are statistically significant. MRMS storms are more concentrated, with smaller areas and higher peak intensities, which implies higher flash flood risks associated with the storms. On the other hand, IMERG storms can travel longer distances with a higher volume of precipitation, which implies higher risk of riverine flooding. Agreement between the datasets is higher for faster-moving hurricanes in terms of the averaged intensity. Finally, MRMS indicates a higher average precipitation intensity during the hurricane’s lifetime. However, in non-hurricanes, the opposite result was observed. This is likely related to MRMS having higher resolution; monitoring the hurricanes from many viewing angles, leading to different signal saturation properties compared to IMERG; and/or the dominance of droplet aggregation effects over evaporation effects at lower altitudes.