Elevated Nocturnal Convection - The Role of Microphysical Processes

该奖项是为参加平原夜间高架对流（PECAN）野外活动而颁发的。PECAN将于2015年夏天在美国中部举行。该项目的重点是在大平原地区经常发生的夜间雷暴复合体。各种观测系统将用于现场实验，包括多架飞机、移动雷达和地面系统，这些系统可以对低层大气中的风和粒子进行分析。该项目将为参与部署NOAA P-3研究飞机的研究人员提供资金。P-3将配备多种传感器，云粒子探测器和机载雷达作为关键测量。研究人员将帮助收集、质量控制和分析数据，以研究夜间高热对流的关键问题。这项研究的主要影响将是更好地预测夜间风暴，这通常伴随着强风和洪水。该项目还将通过让多名研究生参与研究，帮助培养下一代科学家。PECAN活动指导委员会确定了四个主要研究课题：1)夜间对流的启动和中尺度对流星团的早期演化；2)钻孔和其他波状扰动；3)夜间中尺度对流系统的动力学和微物理；4)夜间对流发生和演变预报。本研究将集中于第三个主题。现场云微物理数据、地面和机载雷达数据以及数值模拟模拟结果将用于验证主要假设；中尺度对流系统发展和成熟的层状区域的微物理冷却过程迫使下行气流环流，在稳定的夜间边界层上产生孔洞和中尺度重力波特征，进而集中、组织和维持未来的对流活动。

This award is for participation in the Plains Elevated Convection at Night (PECAN) field campaign. PECAN will take place in the central United States in the summer of 2015. The focus of the project is on overnight thunderstorm complexes that regularly occur in the Great Plains area. A variety of observational systems will be put in place for the field experiment including multiple aircraft, mobile radars, and ground-based systems that can profile the wind and particles in the lower atmosphere. This project will provide funding for researchers to take part in the deployment of the NOAA P-3 research aircraft. The P-3 will have a variety of sensors with cloud particle probes and airborne radar as key measurements. The researchers will help collect, quality control, and analyze the data in order to study the key questions surrounding nocturnal elevated convection. The main impact from this research will be better forecasts of overnight storms, which often come with severe winds and flooding rains. The project will also help train the future generation of scientists by involving multiple graduate students in the research.The steering committee for the PECAN campaign has identified four main research topics to be addressed: 1) Nocturnal convection initiation and early evolution of mesoscale convective clusters; 2) Bore and other wave-like disturbances; 3) Dynamics and microphysics of nocturnal mesoscale convective systems; 4) Prediction of nocturnal convection initiation and evolution. This research will focus on the third topic. In-situ cloud microphysical data, ground based and airborne radar data, and the results of numerical modeling simulations will be used to test the main hypothesis; microphysical cooling processes in developing and mature stratiform regions of mesoscale convective systems force downdraft circulations that create bore and mesoscale gravity wave features on the stable nocturnal boundary layer that in turn focuses, organizes and maintains future convective activity.