Collaborative Research: Kinematic, Microphysical and Electrical Processes Leading to Extreme Lightning Flash Rates over Argentina Using RELAMPAGO Observations

地球上一些规模最大、电活动最活跃的风暴发生在安第斯山脉背风处的阿根廷中西部。这些风暴起源于安第斯山脉的山麓以及塞拉斯山脉Córdoba (SDC)，并产生极端的闪电量，大冰雹，龙卷风和强降雨。该项目的目标是促进对这一未被充分研究的独特强烈风暴区域闪电的特征和原因的理解，以及这些风暴和其他对流风暴在不同环境下导致如此高影响天气的电气化差异。为了实现这些目标，科罗拉多大学（CU）和亨茨维尔阿拉巴马大学（UAH）的研究人员将研究控制风暴电气化的大气条件和物理过程，并与其他高影响天气一起导致极端闪电率。这些强风暴的测量将在计划中的RELAMPAGO（电气化、闪电和中尺度/微尺度过程遥感与自适应地面观测）现场活动中进行，以实现这些目标。这类风暴会对人、财产、农业和基础设施造成危害，对经济造成巨大影响。对所研究的风暴的条件和过程的进一步了解将有助于更好地预报和预报恶劣天气。此外，该项目将支持研究生和博士后研究人员的教育培训。他们将通过独立研究和参与RELAMPAGO实地活动参与科学研究，并有机会与来自众多学科的美国和国际研究人员合作。气象学和电气化之间的一些基本关系还没有完全被理解，包括缺乏关于微物理和运动学过程如何控制深层对流风暴内电荷区发展的知识。美国最近的研究表明，微物理、动力和电行为之间存在区域差异。因此，需要在阿根廷等世界不同地区进行更多的研究，以了解风暴过程、电气化和闪电特征之间的物理联系。来自科罗拉多大学和亚利桑那大学的研究小组将调查控制风暴电气化的环境条件和物理过程，并导致阿根廷中西部严重风暴的极端闪电率。这项研究的目标是促进对产生极端闪电率的风暴的理解，以及对流风暴类型和导致高影响天气的环境中电气化的差异。这包括确定在这些极端严重的风暴中，各种风暴环境、运动学和微物理过程在控制电荷、电荷区域发展和由此产生的闪速和其他特性（例如，类型、大小、极性、电流、电荷中和）中所起的作用。为了实现这一目标，环境、运动学和微物理测量将在能源部（DOE）为期9个月的CACTI（云、气溶胶和复杂地形相互作用）野外活动和计划中的NSF/NASA/NOAA RELAMPAGO（电气化、闪电和中尺度/微尺度过程遥感与自适应地面观测）野外活动中进行。作为RELAMPAGO的一部分，CU和UAH将在密集观测期间（2018年11月1日至12月15日）部署仪器来测量闪电特征、电场和推断强风暴的电荷结构。CU/UAH团队将使用RELAMPAGO期间部署的雷达和大气探测数据来获得热力学、运动学和微物理测量数据。这些将与来自CU/UAH以及NASA的闪电测量一起使用，以分析有利于极端闪电产生的环境条件。它们还将用于研究导致电荷区产生和极端闪电速率的物理云过程。

Some of the largest and most electrically active storms on earth occur in west-central Argentina in the lee of the Andes Mountains. These storms initiate at the foothills of the Andes Mountains as well as the Sierras de Córdoba (SDC) and produce extreme lightning amounts, large hail, tornadoes and heavy rainfall. The goal of this project is to advance the understanding of characteristics and causes of lightning in this understudied region of uniquely intense storms and differences in electrification between these storms and other convective storms in different environments that lead to such high impact weather. Towards these goals, researchers at the University of Colorado (CU) and the University of Alabama in Huntsville (UAH) will study atmospheric conditions and physical processes that control storm electrification and lead to extreme lightning flash rates in conjunction with other high impact weather. Measurements of these severe storms will be taken during the planned RELAMPAGO (Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations) field campaign to be able to address these goals. Such storms have a large economic impact as they pose a hazard to people, property, agriculture and infrastructure. An improved understanding of conditions and processes from the studied storms will lead to better nowcasting and forecasting of severe weather. Furthermore, this project will support educational training of graduate students and a postdoctoral researcher. They will participate in the scientific research through independent studies and participation in the RELAMPAGO field campaign and have the opportunity to collaborate with the US and international researchers from a multitude of disciplines.Some fundamental relationships between meteorology and electrification are not completely understood, including a lack of knowledge of how microphysical and kinematic processes control the development of charge regions inside deep convective storms. Recent studies in the US suggest that regional differences between microphysical, dynamical and electrical behavior exist. Thus, more research in different regions of the world such as in Argentina is needed to understand the physical connections between storm processes, electrification and lightning characteristics. The team of researchers from CU and UAH will investigate the environmental conditions and physical processes that control storm electrification and lead to extreme lightning flash rates of severe storms in west-central Argentina. The goal of the research is to advance understanding of storms producing extreme flash rates and of differences in electrification among convective storm types and environments that lead to high impact weather. This includes determining what role various storm environmental, kinematic and microphysical processes play in governing charge, charge region development and resultant flash rates and other properties (e.g., type, size, polarity, current, charge neutralized) in these extremely severe storms. Towards this goal, environmental, kinematic and microphysical measurements will be taken during the 9-month Department of Energy (DOE) CACTI (Clouds, Aerosols, and Complex Terrain Interactions) field campaign and the planned NSF/NASA/NOAA RELAMPAGO (Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations) field campaign. As part of RELAMPAGO, CU and UAH will deploy instrumentation to measure lightning characteristics, electric fields, and inferred charge structures of severe storms during the Intensive Observing Period (11/1-12/15/2018). The CU/UAH team will use measurements from radars and atmospheric soundings deployed during RELAMPAGO to obtain thermodynamic, kinematic, and microphysical measurements. These will be used together with lightning measurements from CU/UAH as well as NASA to analyze the environmental conditions favoring extreme lightning production. They will also be used to study the physical cloud processes leading to charge region creation and extreme lightning flash rates.