CAREER: Towards a Better Understanding of Turbulence Structures in a Disturbed Atmospheric Surface Layer

职业：更好地理解受干扰的大气表层中的湍流结构

• 批准号: 1112938
• 负责人: Heping Liu
• 金额: $ 42.56万
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-16 至 2016-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1112938&HistoricalAwards=false
• 关键词: CAREER; Towards; Better; Understanding; Turbulence

The Monin-Obukhov similarity theory (MOST) provides numerical weather and climate models with a basis in formulating the turbulent exchange of momentum, energy, water vapor, and other scalars between the Earth's surface and the lower atmosphere. However, several recent studies have identified some features that are not fully consistent with predictions by MOST and attributed these departures to the disturbance of outer-layer, large-scale coherent structures (hereafter referred to as coherent eddies) on locally-generated active turbulence in the atmospheric surface layer (ASL). Although some studies have presented alternative theories to describe these discrepancies, turbulence structures in the disturbed ASL are still poorly understood. The objectives of this project are to study turbulence structures in the stable and unstable ASL beneath a convective boundary layer where a strong interaction between coherent eddies and active turbulence occurs. The datasets from the already completed Energy Balance Experiment will be used. More specifically, this project aims to: 1. Quantify turbulence structures under the influence of large-scale coherent eddies and characterize the deviations of turbulence structures from predictions by MOST under two atmospheric stratifications during the daytime in the disturbed ASL. 2. Investigate how coherent eddies interact with the ASL turbulence and their contributions to flux exchange of momentum, heat, and water vapor under two atmospheric stratifications. 3. Study the spatial structures and temporal evolutions of coherent eddies from time-series data in the ASL to elucidate the origins and sources of coherent eddies. 4. Enhance the Jackson State University Micrometeorology Laboratory and enrich meteorological courses through incorporating research activities and findings of this project in the classroom and teaching laboratories. 5. Involve a large number of African American undergraduate and graduate students and encourage them to take part in the research activities. This program will provide an excellent education and training opportunity for undergraduate and graduate students and will greatly enhance atmospheric sciences education in Jackson State University, one of the nation's largest historically black colleges and universities.

Monin-Obukhov的相似性理论（大多数）提供了数值的天气和气候模型，其基础是制定动量，能量，水蒸气和地球表面和下部气氛之间的动量，能量，水蒸气和其他标量的湍流交换。但是，最近的一些研究已经确定了一些与大多数预测完全不一致的特征，并将这些偏离归因于大气表面层中局部生成的活性湍流（ASL）对局部生成的活性湍流（ASL）的外部层，大规模相干结构（以下称为相干性EDDIE）的干扰。 尽管一些研究提出了描述这些差异的替代理论，但受干扰的ASL中的湍流结构仍然很少了解。该项目的目标是研究在对流边界层下方稳定且不稳定的ASL中的湍流结构，在对流边界层下，相干涡流和主动湍流之间存在强烈的相互作用。将使用已经完成的能源平衡实验的数据集。更具体地说，该项目的目的是：1。在大规模相干涡流的影响下量化湍流结构，并表征湍流结构在干扰ASL中的两个大气分层下的湍流结构与预测的偏差。 2。研究相干涡流如何与ASL湍流相互作用及其对在两个大气层下的动量，热和水蒸气的通量交换的贡献。 3。研究ASL中时间序列数据相干涡流的空间结构和时间演变，以阐明相干涡流的起源和来源。 4。通过将研究活动和研究结果纳入课堂和教学实验室，增强杰克逊州立大学的微观气候实验室和丰富的气象课程。 5。涉及大量非裔美国人的本科生和研究生，并鼓励他们参加研究活动。该计划将为本科生和研究生提供出色的教育和培训机会，并将在杰克逊州立大学（杰克逊州立大学（Jackson State University），这是美国历史上最大的黑人学院和大学之一的杰克逊州立大学的大气科学教育。