Dual Polarization Radar Observations, Analysis and Retrievals of Convective Lifecycle during RELAMPAGO

传统的气象雷达观测风暴是利用单极化来测量风暴内部的强度和速度。过去的研究表明，使用雷达上的两个正交偏振可以获得更多关于风暴、粒子类型和演变阶段的信息。本文主要研究了阿根廷中西部RELAMPAGO试验期间的双极化雷达观测资料。就大冰雹的频率、极高的风暴顶和极端的闪电活动而言，该地区拥有世界上最强烈的对流系统之一，但对该地区的强烈对流仍有许多未知之处。由于该地区风暴的可重复性，本实验将对这些风暴进行观测，以解决与风暴发展的起源、初始组织/恶劣天气产生和生长阶段有关的科学问题，这些问题目前尚不清楚。这项研究将提高对全球强对流风暴的认识和预测能力。类似的环境存在于世界上的许多地方，包括美国的落基山脉和亚洲（如中国的成都盆地和印度次大陆的喜马拉雅平原）。该项目开发的雷达技术有可能使美国所有双偏振雷达的全国部署受益。该项目将具体解决在一些最强烈的对流风暴中分析和检索双极化雷达观测的问题，开发先进的检索技术。RELAMPAGO野外观测的建立将阐明复杂地形与恶劣天气产生之间的紧密联系，地形在有组织对流风暴的产生和发展中的作用及其强度。开发和应用先进的雷达技术，特别是利用频域程序，来识别风暴中降水颗粒的类型，是该项目的重要组成部分。

Traditionally meteorological radars have observed storms using single polarization to measure the intensity and velocity within storms. Past research has shown that significantly more information about the storms, their particle types, and stage of evolution can be gleamed from using two orthogonal polarizations in radars. This research focuses on the dual-polarization radar observations during the RELAMPAGO experiment in west Central Argentina. This region has among the most intense convective systems in the world in terms of frequency of large hail, very high storm tops, and extreme lightning activity, yet much remains unknown about the intense convection in this region. Because of the repeatability of storms in the region, this experiment will observe these storms to address science questions related to the initiation, initial organization/severe-weather generation, and growth stages of storm development, which are poorly understood. This research will improve the understanding of, and the ability to predict, severe convective storms worldwide. Similar environments exist in many parts of the world including the US Rocky Mountains and Asia (such as Chengdu basin in China and Himalayan plains on the Indian subcontinent). The radar techniques developed from this project has the potential to benefit all the nationwide deployment of dual-polarization radars in the US.This project will specifically address the analysis and retrieval of dual-polarization radar observations in some of the most intense convective storms, developing advanced retrieval techniques. The RELAMPAGO field observation set up will elucidate the tight connections between the, complex terrain, and the production of severe weather, role of terrain in initiating and developing organized convective storms and resultant intensity. Development and application of advanced radar techniques, specially using frequency domain procedures, to identify the type of precipitation particles in the storm is an important part of this project.