Multi-Scale Interactions in the Lake Induced Boundary Layer

驱动大气环流的大部分能量是通过与地面的热量、水分和动量交换获得的。五大湖上空的冷气团迅速改变的湖泊效应事件是研究这些交换的极好自然实验室。湖泊诱导对流实验（Lake- ice）是一个由多个首席研究员组成的项目，旨在利用这个自然实验室来确定中尺度边界层对流结构如何控制边界层的生长过程，以及修改后的边界层如何影响降水的产生和更大尺度的气象条件。首席研究员将使用各种原位和远程测量来攻击以下内容目的：确定中尺度环流对边界层顶部夹带过程的调节程度；确定夹带是通过与边界层大涡环流相关的吞没发生的，还是通过小规模的界面混合发生的，并确定过程对大尺度和中尺度条件的敏感性。确定夹带事件对云顶雨滴大小分布的影响。这些目标将通过以下方式实现：编制娱乐事件空间范围的统计数据库；利用雷达垂直层廓线识别云顶夹带过程根据大、中、云尺度条件对统计数据库进行分类；娱乐事件的微观物理影响的案例研究。研究的最终结果将是一个复合的二维反射率和垂直速度结构的中尺度波段，相应的云尺度和交叉逆温湍流强度，以及几个详细的案例研究描述。这将提供一个更好的定量物理理解这些不同尺度的运动之间的相互作用。＊＊＊

9629343 Verlinde Much of the energy that drives atmospheric circulations is obtained through exchanges of heat, moisture, and momentum with the surface. Lake-effect events, where cold air masses are rapidly modified over the Great Lakes, are excellent natural laboratories for studying these exchanges. The Lake- Induced Convection Experiment (Lake-ICE) is a multiple- Principal Investigator project which seeks to use this natural laboratory to determine how boundary layer growth processes are controlled by mesoscale boundary layer convective structures and how the modified boundary layer effects the production of precipitation and the larger scale meteorological conditions The Principal Investigator will use a variety of in situ and remote measurements to attack the following objectives: Determine the extent to which mesoscale circulations modulate the entrainment processes at the top of the boundary layer; Determine if entrainment occurs through engulfment associated with large-eddy circulations n the boundary layer or through small-scale interfacial mixing and determine sensitivity of the processes to large and mesoscale conditions. Determine the impact of entrainment events on the drop size distribution at cloud top. These objectives will be accomplished by: Compiling a statistical data base of the spatial extent of entrainment events; The identification of cloud-top entrainment processes through analysis of radar derived vertical layer profiles; Categorizing the statistical data base according to large-, meso- and cloud-scale conditions; Case studies of the microphysical impact of entrainment events. The final products of the study will be a composite two-dimensional reflectivity and vertical velocity structure of a mesoscale band, with corresponding cloud-scale and cross-inversion turbulence intensity, and several descriptions of detailed case studies. These will provide a better quantitativ e physical understanding of the interaction between these different scales of motion. ***