Spatiotemporal Variability in Cold Pool Properties and Processes

冷池是由雷暴在地球表面产生的凉爽、稠密、阵风的空气区域，对地球系统的许多方面都很重要。例如，冷水池可以引发新的雷暴，增强雷暴、阁楼尘埃和花粉的强度和寿命，并影响飞机运行。该项目的目标是检查冷池性质和物理过程的可变性。特别是，研究重点是冷水池的湍流特征，以及冷水池如何受到陆地表面特性的空间差异的影响，例如土壤中的水量或现有的植被类型。该项目的结果将为天气和预报模型对冷池的模拟及其对新风暴形成、强度和寿命的影响提供信息。研究结果还可用于改进冷池和陆地-大气相互作用的气候模型。该项目将支持研究生论文，研究成果将被纳入研究生水平的课程以及针对STEM领域中代表性不足的群体的教育和推广活动。本研究的总体目标是调查中纬度深对流冷池属性和过程的时空变异性，特别是它们的湍流特征及其与陆地表面和边界层中非均质性的相互作用。这项研究将填补关于冷池变化的主要时空尺度及其与陆面非均质性相互作用的关键知识空白，这可能在冷池影响中发挥重要作用，如对流的启动和结构，以及局部化的暴雨和地面风。该项目将包括利用在CSU对流云外流和上升气流实验(C3LOUD-Ex)期间收集的观测数据来表征中纬度冷池属性的时空变异性。此外，将使用理想化和案例研究模拟来探索陆地表面特征的非均质性如何在物理过程水平上直接(通过地表通量的变化)和间接(通过对边界层环流的影响)影响冷池可变性。更好地了解这些物理过程将提高对对流启动和行为、风暴组织和寿命、陆地-大气相互作用以及冷池在气候变化中的作用的理解和预测。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Cold pools are regions of cool, dense, gusty air that are produced at the earth’s surface by thunderstorms and are important to many aspects of the earth system. For example, cold pools can initiate new thunderstorms, enhance the intensity and lifetime of thunderstorms, loft dust and pollen, and impact aircraft operations. The objective of this project is to examine the variability in cold pool properties and physical processes. In particular, the research focuses on the turbulent characteristics of cold pools and how cold pools are impacted by spatial variations in land surface properties such as the amount of water in the soil or the type of vegetation present. The project results will inform weather and forecast models’ simulations of cold pools and their impacts on new storm formation, intensity, and longevity. The results could also be used to improve climate model representations of cold pools and land-atmosphere interactions. A graduate student thesis will be supported by the project, and the research findings will be incorporated into graduate-level courses and education and outreach activities to underrepresented groups in STEM fields.The overarching objective of this research is to investigate the spatiotemporal variability in midlatitude deep convective cold pool properties and processes, particularly their turbulent characteristics and their interactions with heterogeneities in the land surface and the boundary layer. The research will fill a critical knowledge gap regarding dominant spatial and temporal scales of variability in cold pools and their interactions with land surface heterogeneities, which may play important roles in cold pool impacts such as convective initiation and structure, and localized heavy rainfall and surface winds. The project will include a characterization of spatiotemporal variability in midlatitude cold pool properties using observations collected during the CSU Convective CLoud Outflows and UpDrafts Experiment (C3LOUD-Ex). Additionally, idealized and case study simulations will be used to explore how heterogeneities in land surface characteristics impact cold pool variability both directly (through variations in surface fluxes) and indirectly (through impacts on boundary layer circulations) at a physical process level. Better knowledge of these physical processes will improve the understanding and predictions of convective initiation and behavior, storm organization and longevity, land-atmosphere interactions, and the role of cold pools in changing climates.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.