Collaborative Research: Data Assimilation Analysis of the Boundary Layer and Convection Initiation During International H2O Project (IHOP)

合作研究：国际H2O项目（IHOP）期间边界层和对流引发的数据同化分析

• 批准号: 0638572
• 负责人: Conrad Ziegler
• 金额: $ 17.49万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-01-15 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0638572&HistoricalAwards=false
• 关键词: Collaborative; Research; Data; Assimilation; Analysis

The field phase of the International H2O Project (IHOP_2002) provided a wide range of mesoscale meteorological observations to help improve understanding of the scales of, and processes influencing, the atmospheric boundary layer (ABL), convection initiation (CI) and quantitative precipitation forecasting (QPF). Previous research focused on the collection and analysis of targeted mobile field observations, the analysis of the preconvective boundary layer structure and evolution, and the cumulus formation and convection inhibition/initiation processes. The goal of this research is to provide new understanding of the dynamics of boundary layer circulations and the related processes leading to cumulus formation and CI by applying advanced data assimilation tools for the first time to additional IHOP cases. Intellectual Merit: The Principal Investigators will continue analysis of 3-D radar-derived boundary layer airflow and in-situ measurements of winds and thermodynamic parameters from mobile mesonets, soundings, aircraft, and other targeted mobile and fixed IHOP platforms. The combination of boundary layer airflow with in-situ measurements of absolute humidity and virtual temperature provide the only means of documenting the dynamical and transportive processes acting in the boundary layer to regulate precipitable water and force the development of secondary circulations and clouds or storms. Thus, new analyses of IHOP observations are essential to continue evaluating all hypotheses concerning the impact of water vapor supply and airflow evolution on boundary formation and CI in different mesoscale environments. Detailed IHOP observations will be analyzed in several different ways. Subjective analyses and visualizations will be produced incorporating all available data on the relevant scales for CI. Observation density will be enhanced utilizing a Lagrangian analysis developed under the previous grant that distributes nearly conserved variables along Lagrangian trajectories based on multiple-Doppler wind syntheses. Finally, the potential of assimilating these enhanced observations directly into a cloud/mesoscale model using the Ensemble Kalman Filter method will be assessed to determine the dynamical forcing processes controlling the development of localized boundary layer and lower tropospheric circulations that either promote or prevent CI. Thus, the research will substantially augment and complement other ongoing data assimilation studies of storms and mesoscale convective systems and contribute to a more seamless, end-to-end methodology for mesoscale data assimilation at all scales affecting storm formation and evolution and numerical forecasting of storms. Broader Impacts: This effort will advance the ongoing analysis of an unprecedented data set at previously unobserved scales. The proposed work involves graduate students - thus contributing to the training of the next generation of researchers - while promoting research partnerships between the collaborating institutions. Through the combination of the previous and ongoing analyses, new understanding will emerge regarding the processes occurring in the heterogeneous convective boundary layer near low-level boundaries and relate those processes to the formation of thunderstorms. The knowledge gained will be useful for developing new advances, both numerical and subjective, in data assimilation and quantitative precipitation forecasting by improving the ability to forecast if, when, and where convection will develop.

国际H2O项目（IHOP_2002）的现场阶段提供了广泛的中尺度气象观察，以帮助提高对影响和过程影响的量表，大气边界层（ABL），对流引发（CI）和定量降水预测（QPF）的理解。 先前的研究重点是对目标移动场观测值的收集和分析，对智前边界层结构和进化的分析以及积云的形成和对流抑制/启动过程。 这项研究的目的是通过首次将高级数据同化工具应用于其他IHOP案例，对边界层循环的动态以及导致积云形成和CI的相关过程提供新的了解。智力优点：主要研究人员将继续分析3D雷达衍生的边界层气流以及对移动中套，声音，飞机以及其他有针对性的移动和固定IHOP平台的风和热力学参数的原位测量。 边界层气流与绝对湿度和虚拟温度的原位测量的组合提供了记录在边界层中作用的动态和运输过程的唯一手段，以调节可溶水并迫使二次循环以及云或风暴的发展。 因此，对IHOP观察的新分析对于继续评估有关水蒸气供应和气流演化对不同中尺度环境中边界形成和CI的影响的所有假设至关重要。详细的IHOP观察将通过几种不同的方式进行分析。 将产生主观分析和可视化，并在CI的相关尺度上纳入所有可用的数据。 利用先前赠款中开发的拉格朗日分析，将增强观察密度，该分析基于多个多普勒风合成，沿拉格朗日轨迹分布了几乎保守的变量。 最后，将评估将这些增强的观测值直接吸收到云/中尺度模型中的潜力，以确定控制局部边界层开发的动力强迫过程和促进或预防CI的对流层循环的发展。 因此，这项研究将大大增加和补充其他正在进行的数据同化研究，对风暴和中尺度对流系统，并在所有尺度上都有更无缝的，端到端的方法，用于中尺度数据同化，影响风暴形成，进化和数值暴风雨的预测。更广泛的影响：这种努力将在先前未观察到的量表上进行对前所未有的数据集的持续分析。 拟议的工作涉及研究生 - 从而为下一代研究人员的培训做出了贡献 - 同时促进合作机构之间的研究合作伙伴关系。 通过以前和正在进行的分析的结合，将出现关于在低水平边界附近的异质对流边界层中发生的过程的新理解，并将这些过程与雷暴的形成联系起来。 获得的知识将有助于开发数值和主观的新进步，在数据同化和定量降水预测中，通过提高预测能力，何时以及对流的何处以及在何处的何处进行预测。