The Structure of Mesoscale Convective Systems as Revealed from Detailed Surface Mesoanalyses during the Bow Echo and Mesoscale Vortex Experiment (BAMEX)

将于2003年5月20日至7月6日举行的弓形回波和中尺度涡旋实验（BAMEX）将利用多个最先进的观测平台，结合各种常规观测，产生全面综合的数据集，帮助记录一类重要的中尺度天气现象的产生、成熟、衰减和整体生命周期。弓形回波和中尺度对流涡（mcv）与中尺度对流系统（mcs）一起发生。恶劣天气，包括冰雹、大风和龙卷风，经常与mcs、嵌入式mvc和弓形回波有关。在母体mcs之后留下的残余mcv也可以旋转新的深层对流并重新点燃新的mcs。预测MCS将在何时何地形成，它将向何处移动，以及它将持续多久，仍然是一个令人烦恼的问题。BAMEX有机会利用特殊的数据集捕捉多个MCS生命周期，从中可以增加对控制MCS行为的物理机制的科学理解，这是改进MCS预测的必要的第一步。这项研究的动机是需要准备全面的研究质量细观分析，以便更多地了解弓回波和mcv通常“隐藏”的表面结构，以及地表环流如何与地表以上环流联系起来。首席研究员将：(1)通过详细的地面中观分析，在空间和时间上记录首次和随后形成的MCS生命周期；(2)确定地表边界（外流、锋面、干线）如何调节MCS生命周期，而这些生命周期又被对流调制，然后受到连续的MCS的影响；(3)评估地表锋生过程如何迫使影响MCS生命周期的中尺度环流；(4)将尾流槽和低点、气泡高点等地表特征联系起来；以及多个气旋涡度最大值到低层和中层涡、中高层位势涡度异常、后入流射流、云对地闪电模式以及雷达、飞机和卫星衍生的MCS特征。详细的地表中尺度分析将使用人工和自动程序相结合的方法来准备，这些程序利用时间-空间转换技术来更好地绘制中尺度特征。地面和自由大气环流之间的联系将与BAMEX的其他研究人员合作探讨。这项研究的成功完成将有助于更好地预报强风事件和对流风暴。

The Bow Echo and Mesoscale Vortex Experiment (BAMEX) to be held from 20 May to 6 July 2003 will take advantage of multiple state-of-the-art observational platforms together with a variety of conventional observations to produce comprehensive integrated datasets to help document the birth, maturation, decay, and overall life cycles of an important class of mesoscale weather phenomena. Bow echoes and mesoscale convective vortices (MCVs) occur in conjunction with mesoscale convective systems (MCSs). Severe weather, including hail, high winds, and tornadoes, frequently occurs in association with MCSs and embedded MVCs and bow echoes. Remnant MCVs left behind in the wake of parent MCSs can also act to spin up new deep convection and reignite new MCSs. Forecasting where and when a MCS will form, where it will track, and how long it will last remains a vexing problem. An opportunity exists with BAMEX to capture multiple MCS life cycles with special datasets out of which can come increased scientific understanding of the physical mechanisms that govern MCS behavior, a necessary first step to making improvements in forecasting MCSs. This research is motivated by the need to prepare comprehensive research quality mesoanalyses in order to learn more about the often "hidden" surface structure of bow echoes and MCVs and how surface circulations are linked to circulations above the surface. The Principal Investigator will: (1) document first, and subsequent, generation MCS life cycles spatially and temporally through detailed surface mesoanalyses, (2) determine how surface boundaries (outflow, frontal, dryline) modulate MCS life cycles, are in turn modulated by the convection, and then influenced by successive MCSs, (3) evaluate how surface frontogenesis processes force mesoscale circulations that influence MCS life cycles, and (4) relate surface features such as wake troughs and lows, bubble highs, and multiple cyclonic vorticity maxima to low- and mid-level vortices, mid- and upper-level potential vorticity anomalies, rear-inflow jets, cloud-to-ground lightning patterns, and radar-, aircraft- and satellite-derived MCS signatures. The detailed surface mesoanalyses will be prepared using a combination of manual and automated procedures that take advantage of time-to-space conversion techniques to better map mesoscale features. The linkage between surface and free-atmosphere circulations will be explored in cooperation with other BAMEX investigators.Successful completion of this research may lead to better forecasts of severe wind events and convective storms.