Precision Atmospheric Marine Boundary Layer Experiment (PREAMBLE)

一个实地项目将于2011年5月20日至6月20日在加利福尼亚州的Point Conept附近进行。这项野外试验的基本目的是直接测量海洋大气边界层(MABL)内风场的动力强迫。这项研究将集中于与夏季加州海岸常见的偏北低层海岸急流有关的动力学问题。由于强偏北风与加利福尼亚州海湾气旋环流的交界处存在许多潜在的非线性相互作用(因此可能难以模拟)，因此有必要对该地区的气象变量进行直接测量，以解析MABL的重要分量及其相互作用。如果卡特琳娜涡旋和/或被困在海岸的风向逆转，将进行专门的飞行，以探索与这些事件相关的动力学和热力学。智力上的优点。怀俄明大学国王航空公司(UWKA)的飞机将部署在加州海岸，这已经在之前的研究项目中使用。计划总共飞行50个小时。该项目将建立在最近开发的机载技术的基础上，该技术能够通过对机载平台的GPS高度进行差分校正来检测微小的水平压力信号。这样的测量将允许对大气层内水平气压梯度的精细评估，从而允许分析水平运动方程中的强迫项。通过空中采样可以确定MABL流的非地转风和加速。此外，还要求将怀俄明大学的云雷达和云激光雷达作为UWKA上仪器的一部分。这种仪器将能够测量随之而来的云层特性，如云层高度和微物理参数。UWKA上的标准云物理探测器还将允许进行许多其他云和微物理测量。在卡特琳娜涡旋或海岸滞留风倒转的条件下，衡量大气边界层动力学的一个关键指标是大气边界层的高度。从机载飞行任务获得的有关MABL内湿度和温度垂直结构的详细信息，将有助于在这一具有战略敏感性的区域对微波折射率分布进行精细测定。空中观测数据集将得到相当多的地面仪器的补充，包括围绕点概念的一系列浮标。收集的数据将为与高分辨率(~1公里)数值模拟与天气研究和预报模式(WRF)的比较提供基础。点构区具有重要的战略意义和国家安全利益。在过去的二十年里，沿海环境中的气象现象促使了几项重大的研究工作。作为这次实地实验的一部分，收集的数据将提供独特和前所未有的测量结果，这将有助于验证以前的概念模型和努力对详细的MABL动力学进行数值模拟。该项目将为研究生提供大气科学观测方面的培训机会，这一重点被确定为2009年6月高级研究方案座谈会的关键要素。与之前的实地实验一样，研究生将有机会计划一项研究任务，并在UWKA上担任飞行科学家。怀俄明大学已经启动了一个新的学术项目--地球系统科学，该项目的数据将作为大气动力学项目的一部分用于一个研究项目。

A field project will be conducted from 20 May - 20 June 2011 near the Point Conception, California. The fundamental goal of this field experiment is to directly measure the dynamic forcing responsible for the wind field within the marine atmospheric boundary layer (MABL). The study will focus on dynamics associated with the northerly low-level coastal jet that is commonplace in the California coasts during summer. Because there are many potentially non-linear interactions occurring at the interface of the strong northerly (thus potentially difficult to simulate), along-shore wind regime with the cyclonic circulation within the California Bight, direct measurements of meteorological variables in this region are necessary to pars out the important components and their interactions at MABL. If a Catalina eddy and/or coastally-trapped wind reversal should occur, dedicated flights will be conducted to explore the dynamics and thermodynamics associated with those events. Intellectual merit. The University of Wyoming King Air aircraft (UWKA) will be deployed in the California coasts, which has been used in previous research projects. A total of 50 flight hours are planned. This project will build on recently developed airborne technology that enables detection of small horizontal pressure signals using differential correction of GPS heights of an airborne platform. Such measurements will allow fine-scale assessment of the horizontal pressure gradient at levels within the MABL, and thus permit analysis of the forcing terms in the horizontal equations of motion. Determination of ageostrophic winds and accelerations of the MABL flows will be possible from the airborne sampling. In addition, a request has been made for inclusion of the University of Wyoming Cloud Radar and Cloud Lidar as part of the instrumentation onboard the UWKA. Such instrumentation will enable measurements of attendant cloud properties, such as cloud height and microphysical parameters. The standard cloud physics probes on the UWKA will also allow a host of other cloud and microphysical measurements. A critical measurement for dynamics of the MABL under conditions of a Catalina eddy or coastally trapped wind reversal is the height of the MABL stratus. Detailed information regarding the vertical structure of humidity and temperature within the MABL from the airborne missions will enable fine-scale determination of microwave refractivity profiles in this strategically sensitive region. The airborne observational dataset will be supplemented with the considerable body of surface-based instrumentation including a host of buoys surrounding Point Conception. Data collected will provide the basis for comparison with high-resolution (~ 1 km) numerical simulations with the Weather Research and Forecasting Model (WRF).Broader impacts. The Point Conception area is of strategic importance and national security interests. Meteorological phenomena in the coastal environment have prompted several major research efforts during the past two decades. Data collected as part of this field experiment will provide unique and unprecedented measurements that will be useful for validation of previous conceptual models and efforts to numerically simulate detailed MABL dynamics. This project will offer an opportunity for graduate student training in the observational aspects of atmospheric science, a focus from that was identified as a key element for the June 2009 Advanced Study Program Colloquium. As with previous field experiments, graduate students will have an opportunity to plan a research mission and serve as flight scientist on the UWKA. A new academic program, Earth System Science, has been initiated at the University of Wyoming and data from this project will be used in a research project as part of an atmospheric dynamics project.