Studies of Convection, Microphysics and Lightning in the Deep Convective Clouds and Chemistry Experiment (DC3)

深对流云中的对流、微物理和闪电研究及化学实验（DC3）

• 批准号: 1429925
• 负责人: Steven Rutledge
• 金额: $ 67.53万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1429925&HistoricalAwards=false
• 关键词: Studies; Convection; Microphysics; Lightning; Deep

With this award, the investigators will carry out comprehensive studies of the data collected during the Deep Convection, Clouds and Chemistry Experiment (DC3) conducted during May-June 2013. DC3 collected a comprehensive dataset on cloud dynamics, microphysics and chemistry in a variety of convective events, over three regions, the southeast U.S., the Southern Great Plains and over the semi-arid region of eastern Colorado. The research will address two of the overarching goals of the DC3 program; understanding the gross electrical structure of storms and why particular storms have a so-called "inverted" electrical polarity; and improving our understanding regarding the production of Nitrogen Oxides (NOx) by lightning. The work concerning the electrical structure of storms will utilize comprehensive Doppler and polarimetric radar and lightning mapping network data obtained in DC3 and will include a small sample of storms affected by the High Park wildfire in Colorado. Under the objective to improve how lightning-generated NOx is handled in cloud-chemistry models, the research team will use Lightning Mapping Array observations of total lightning flash rates to improve flash rate parameterizations, contribute to storm scale budget studies aimed at estimating the amount of NOx produced per lightning flash, and refine assumptions regarding where the lightning-generated NOx is "released" into the storm. The research team will relate detailed observations of ice particle types in anvil clouds (aggregates of frozen droplets) to the adjacent deep convection. Under this award, the research team will develop a number of collaborations to enhance this research, including collaborations with scientists that are conducting cloud-chemistry simulations of several DC3 cases using the Weather Research Forecasting-Chemistry (WRF-Chem) model.This research will contribute to the knowledge base regarding the coupling between cloud dynamics, microphysics and electrification/lightning. The research will utilize state of the art radar and lightning mapping information in order to improve our understanding of so-called "inverted" charge structures where positive electrical charge resides in the storm mid-levels, opposed to the more typical structure where negatively-charged hydrometeors resides at mid-levels. Utilizing the comprehensive measurements from DC3,the research team will also address the lightning-NOx problem, that is, quantifying the amount of NOx released in a storm produced by lightning. This work will be done from the point of view of improving required parameterizations for these processes in cloud-chemistry models. Hence this work will be interdisciplinary in nature, bringing together cloud physics and atmospheric chemistry specialists. This work will also improve our understanding as to how deep convection contributes to anvil ice water contents and ice particle types. Hence this work may lead to a better understanding regarding the radiative properties of anvils attached to strong convection. DC3 observations are expected to advance our understanding regarding storm dynamics, microphysics and electrification. Knowledge of these processes will provide a basis for improving the manner by which lightning-generated NOx (LNOx) is considered in cloud-chemistry models. The role of LNOx in contributing to upper tropospheric ozone, a greenhouse gas, can then be improved. In general DC3 results are expected to improve our understanding regarding the impact of deep convection on the chemical composition of the UTLS (upper troposphere-lower stratosphere). Experimental data from the DC3 project will provide important datasets for model comparison exercises and assessment reports.

With this award, the investigators will carry out comprehensive studies of the data collected during the Deep Convection, Clouds and Chemistry Experiment (DC3) conducted during May-June 2013. DC3 collected a comprehensive dataset on cloud dynamics, microphysics and chemistry in a variety of convective events, over three regions, the southeast U.S., the Southern Great Plains and over the semi-arid region of eastern Colorado.该研究将解决DC3计划的两个总体目标；了解暴风雨的总电节结构，以及为什么特定风暴具有所谓的“倒置”电极性；并通过闪电提高我们对氮氧化物（NOX）产生的理解。关于风暴的电气结构的工作将利用DC3中获得的综合多普勒和极化雷达以及闪电映射网络数据，其中包括一小部分受科罗拉多州高公园野火影响的风暴。在改善云化学模型中如何处理闪电生成的NOX的目标下，研究团队将使用闪电映射阵列的总闪电闪光速率观察来提高闪光速率参数，旨在促进风暴量表预算研究，旨在估算估算每个Lightning Flash产生的NOX的数量，并就灯火闪烁的何处进行了针对Nox的假设。研究团队将将冰粒类型的详细观察结果与邻近的深对流有关。根据该奖项，研究团队将使用天气研究预测化学化学（WRF-CHEM）模型进行许多合作来增强这项研究，包括与正在对几个DC3案例进行云化学模拟的合作。这项研究将有助于有关云动力学，微观噬菌体和电子化和电子化和电子化和电子化和电子化和电子化学之间的知识的有助于知识基础。这项研究将利用最新的雷达和闪电映射信息，以提高我们对所谓的“倒”电荷结构的理解，在这种情况下，正面电荷位于暴风雨中层中，与更典型的结构相反，较典型的水力含量的水合居住在中层中。利用DC3的全面测量结果，研究团队还将解决闪电诺克斯问题，即量化闪电产生的风暴中释放的NOX数量。这项工作将从改进云化学模型中这些过程所需的参数化的角度来完成。因此，这项工作本质上将是跨学科的，将云物理和大气化学专家汇总在一起。这项工作还将提高我们对对流对砧冰水含量和冰颗粒类型的贡献的理解。因此，这项工作可能会使人们更好地了解与强对流相关的铁砧的辐射特性。 DC3观察结果有望提高我们对风暴动态，微物理和电气化的理解。这些过程的知识将为改善云化学模型中考虑闪电生成的NOX（LNOX）的方式提供基础。 LNOX在促进对流层臭氧（一种温室气体）中的作用可以改善。 通常，DC3结果预计将提高我们对深对流对UTL（对流层平流层上层）化学成分的影响的理解。 DC3项目的实验数据将为模型比较练习和评估报告提供重要的数据集。