Collaborative Research: Fundamental Investigations of Modeling for LES of Atmospheric Boundary Layer Flow Near the Land Atmosphere Interface

本研究的主要目的是在小于大涡模拟(LES)所用网格最小间距的空间尺度上研究大气边界层(ABL)中的空气运动和输送，并利用所获得的知识来改进大涡模拟中的参数化。大涡模拟在提高我们对陆地-大气相互作用的理解方面发挥着越来越重要的作用，这与大气边界层有关。了解这种相互作用对于气候和中尺度模式都很重要。研究将以现场测量为基础，使用目前正在开发的声波风速计阵列和激光雷达测速仪。将有两个实地活动。其中一次将在爱荷华州爱荷华市附近举行。它将包括一系列三维声波风速计和快速响应热膜传感器。该场地主要由一片草地组成。数据将在六周内收集。第二个现场活动将在加利福尼亚州戴维斯附近进行，为期一个月，将使用测风激光雷达和弹性激光雷达来研究ABL的深度、声波风速计阵列和标准的流量-能量平衡仪器。该项目的主要成果将是大涡模拟将能够更真实地模拟大气边界层中的湍流。

The main objective of this research is to study air motion and transport in the Atmospheric Boundary Layer (ABL) at spatial scales smaller than the smallest spacing of the grids used in Large-eddy Simulations (LES), and to use the knowledge gained to improve parameterizations in LES. Large-eddy simulation is playing an increasingly important role in improving our understanding of land-atmosphere interaction at scales that are relevant in the ABL. Understanding of this interaction is important for both climate and mesoscale models. The studies will be based on field measurements using arrays of sonic anemometers and a lidar velocimeter currently being developed. There will be two field campaigns. One will take place near Iowa City, IA. It will include an array of three-dimensional sonic anemometers and fast-response hot-film sensors. The site consists primarily of a grass field. Data will be collected over a six-week period. The second field campaign will take place near Davis, CA over a one-month period and will use the wind lidar and elastic lidar to study the depth of the ABL, arrays of sonic anemometers and standard flux-energy balance instrumentation. The main result of this project will be that LES will be able to simulate turbulence in the atmospheric boundary layer more realistically.