EAGER: Opportunistic Soundings to Advance the Understanding of High-Shear Low-CAPE (Convective Available Potential Energy) Convective Environments

在以大垂直风切变和边际对流可用势能（所谓的“高切变、低cape”或“HSLC”环境）为特征的环境中发生的强对流风暴对社会构成了重大威胁，但人们对它们的认识仍然很少。最近的研究表明，在所有恶劣天气报告中，包括重大龙卷风（增强的藤田规模的EF2或更大），有很大一部分发生在HSLC环境中。HSLC情况在全国范围内全年都有发生，但在寒冷季节和夜间特别常见，因为公众对恶劣天气威胁的认识较低。与cape较高的对流相比，HSLC环境中的风暴的空间尺度相对较小，典型的回波顶为4-6 km AGL，而中气旋的宽度和深度仅为2-4 km，因此雷达对它们的采样也往往很差。总而言之，由于其潜在的严重性，它们通常发生在一天和一年的非传统时间，以及它们给基于雷达的预警操作带来的困难，HSLC风暴值得关注。我们在知识基础上的差距体现在恶劣天气监测和高低温风暴预警的技能相对较低。在最基本的层面上，高低温天气预报受到阻碍，因为我们对高低温天气风暴的基本过程及其与周围环境的相互作用了解甚少。如果没有对高温变暖环境的有针对性的观测，我们对高温变暖风暴的理解就不太可能得到改善。本应用程序的目标是在高分辨率的HSLC环境中进行局部探测测量。作业将利用现有的北卡罗莱纳州立大学（NCSU）探测系统，该系统将使研究团队能够快速协调发射，并以极低的成本瞄准不断发展的情况。研究小组将使用收集到的数据来量化HSLC制度中的环境变异性，并确定迄今为止用于HSLC研究的其他代理数据集的优势和劣势。智力优势：HSLC恶劣天气是一个重要的社会问题，需要进一步研究。不幸的是，一个完整的基础研究项目不可能解决这个问题，直到有了一个高质量的观察基线。HSLC环境每年存在许多小时，但它们在任何一天产生恶劣天气的条件概率相对较低。因此，研究小组将进行一项勘探工作，而不是进行一次延长的现场活动（毫无疑问，这将有不可接受的“停机时间”），这一工作成本低廉，并且能够在HSLC对流普遍存在的地区机会主义地瞄准最有希望的日子。项目期间将包括两个不同的寒冷季节，在短期拨款期间最大限度地采样多种HSLC环境的可能性。这项工作具有潜在的变革性，因为它将产生第一组在HSLC环境中进行的时间密集测量，从而为未来的基础科学奠定基础。更广泛的影响：所有探空发射将由NCSU学生执行。除了吸收研究团队的研究生外，PI还担任NCSU学生管理的测深俱乐部的联合顾问。这些学生在准备和发射探测以及分析收集到的数据方面获得了实践经验。他们目前的资助模式只允许他们每年进行2-4次探测。研究小组将邀请探深俱乐部参与所有的发射，这将大大增加可用的发射机会，并将提供有趣的天气和恶劣天气的教育数据。PI还将把这些数据（通常是接近实时的）纳入他的中尺度气象学课程。

Severe convective storms within environments characterized by large vertical wind shear and marginal convective available potential energy (so-called "high-shear, low-CAPE", or "HSLC" environments) present a substantial threat to society, and yet they remain poorly understood. Recent studies indicate that a substantial fraction of all severe weather reports, including significant tornadoes (EF2 or greater on the enhanced Fujita scale), occur within HSLC environments. HSLC conditions occur nationwide and throughout the year, but are particularly common during the cool season and overnight, when public awareness of the severe weather threat is low. Storms within HSLC environments also tend to be poorly sampled by radar due to their comparatively small spatial dimensions compared to higher-CAPE convection, with typical echo tops of 4-6 km AGL, and mesocyclones having widths and depths of only 2-4 km. Taken altogether, HSLC storms are a significant concern due to their potential severity, their typical occurrence during non-traditional times of the day and year, and the difficulties they present to radar-based warning operations. The gap in our knowledge base is manifested in terms of the relatively low skill of severe weather watches and warnings for HSLC storms. At the most basic level, HSLC forecasts are hindered because we have very little understanding of the fundamental processes governing HSLC storms and their interactions with the ambient environment. Without targeted observations of HSLC environments, our understanding of HSLC storms is unlikely to improve.The goal of this application is to undertake a program of local sounding measurements in HSLC environments at high temporal resolution. Operations will exploit the existing North Carolina State University (NCSU) sounding system, which will enable the research team to quickly coordinate launches and to target evolving cases at very low cost. The research team will use the collected data to quantify the environmental variability in HSLC regimes and identify the strengths and weaknesses of other proxy datasets that have heretofore been used for HSLC research.Intellectual Merit:HSLC severe weather is an important societal concern that requires further research. Unfortunately, a full basic research project addressing this problem is not likely until a baseline of quality observations has been made. HSLC environments are present for many hours each year, yet their conditional probability of producing severe weather on any given day is relatively low. Thus, rather than mounting an extended field campaign (which would no doubt have an unacceptable amount of "down time"), the research team will conduct an exploratory work that is inexpensive and is able to opportunistically target the most promising days within a region where HSLC convection is common. The project period will include two distinct cold seasons, maximizing the likelihood of sampling a diversity of HSLC environments during a short grant. This work is potentially transformative because it will produce the first set of temporally dense measurements ever made in HSLC environments, thereby serving as a foundation for future basic science.Broader Impacts:All sounding launches will be performed by NCSU students. In addition to incorporating graduate students from the research team, the PI serves as co-advisor for the student-run soundings club at NCSU. These students gain hands-on experience in preparing and launching soundings, as well as analyzing the data collected. Their current funding model only allows them to launch 2-4 soundings per year. The research team will invite the soundings club to participate in all launches, which will greatly enhance the number of available launch opportunities, and will provide educational data from interesting days with severe weather potential. The PI also will incorporate the data (often in near-real time) into his course on Mesoscale Meteorology.