The effects 9of inhomogeneous drop size distributions (DSDs) in a radar volume, vertical structure and spectral modes of DSDs

雷达体积中不均匀液滴尺寸分布 (DSD) 的影响 9、DSD 的垂直结构和光谱模式

• 批准号: 5448365
• 负责人: Dr. Gerhard Peters
• 金额: --
• 依托单位: Meteorologisches Institut (MI)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5448365?language=en
• 关键词: effects; 9of; inhomogeneous; drop; size

MRR data obtained during a time period of several years will be analyzed, in order to answer basic questions raised in section 4 of the overview. The fine spatial resolution of the MRR data relative to weather radars as well as its disdrometer functionality with much finer temporal resolution as compared with conventional disdrometers allow to investigate the effects of instationarity and inhomogeneity of drop distributions on Z-R-relations in a quantitative sense. The height-resolved information provided by MRRs will be used to establish characteristics of height profiles of drop size distributions. These results provide a novel data base for relating radar observable reflectivity patterns, analyzed in other co-projects of this proposal, to the micro physical properties of precipitation. In addirion the data will help to validate advanced microphysical models. The MRR data will be also analyzed to obtain statistical data about frequency, intensity, height and extension of the bright band, in order to assess the general impact of this feature on radar-based QPE. In addition, case studies shall reveal how reliably and with which fidelity the bright band can be captured by weather radars in their operational mode. The analysis of vertical precipitation structure includes also the question, how often and with which intensity shallow precipitation occurs at the MRR sites; i.e. precipitation profiles with too small vertical extension to be detectable by weather radar. In a special experimental effort using arrays of MRRs we will attempt to track individual rain cells in order to observe the temporal development of drop size distributions within a rain cell. In addition, the transformation of drop size distributions on the fall path will be analyzed. These observations will provide a unique handle to assess the realism of spectral rain models and of their description of microphysical processes governing the formation of drop size distributions. This ambitious goal shall be achieved in a joint special observation period together with various synchronized auxiliary measurements as described in more detail in the work plan. In order to utilize the results for improved weather radar rainfall estimates, statistical or physically based relations will be searched between the finescale MRR observations and characteristic pattern features of simultaneously measured weather radar reflectivity fields, as analyzed in other AQUARADAR sub-projects.

将对几年期间获得的减少残留率数据进行分析，以回答概述第4节提出的基本问题。相对于天气雷达的MRR数据的精细空间分辨率以及与传统的disdrometers相比具有更精细的时间分辨率的disdrometer功能允许在定量意义上研究液滴分布的不稳定性和不均匀性对Z-R关系的影响。由MRR提供的高度分辨信息将用于确定液滴尺寸分布的高度剖面特征。这些结果提供了一个新的数据库，雷达可观测的反射率模式，在其他合作项目的分析，降水的微观物理特性。此外，这些数据将有助于验证先进的微物理模型。还将分析MRR数据，以获得关于亮带的频率、强度、高度和延伸的统计数据，以评估该特征对基于雷达的QPE的一般影响。此外，案例研究应揭示天气雷达在其工作模式下捕获亮带的可靠性和保真度。垂直降水结构的分析还包括这样一个问题，即在MRR站点发生浅层降水的频率和强度;即降水廓线的垂直延伸太小，无法被气象雷达探测到。在一个特殊的实验努力，使用阵列的MRR，我们将试图跟踪单个雨细胞，以观察在一个雨细胞内的液滴大小分布的时间发展。此外，还将分析液滴尺寸分布在下落路径上的变化。这些观测结果将提供一个独特的处理，以评估光谱雨模型的现实主义和他们的描述的微物理过程中形成的液滴大小分布。这一雄心勃勃的目标将在一个联合特别观察期内实现，同时进行工作计划中更详细说明的各种同步辅助测量。为了利用这些结果改进天气雷达降雨估计，将在细尺度MRR观测与同时测量的天气雷达反射率场的特征模式特征之间搜索统计或物理基础关系，如AQUARADAR其他子项目中所分析的那样。