Mesoscale Studies of Convection and Tornadogenesis

发生在小空间和时间尺度（中尺度）上的物理强迫常常决定各种天气现象的时间、地点和严重程度。首席研究员建议将中尺度分析的原理应用于各种天气现象，包括龙卷风的形成、研究边界层中的对流（即所谓的水平对流作用），以及研究海洋气旋的形成。龙卷风形成研究的重点是确定导致某些强雷暴产生龙卷风而其他强雷暴不产生龙卷风的物理因素。首席研究员将参加核查龙卷风起源实验的第二阶段，并在1994年春季继续分析第一阶段收集的数据。这项研究的一个独特方面是首次使用机载多普勒数据来研究龙卷风的形成。水平对流作用的研究是对流和降水/电气化期间收集的数据分析的延续。这项研究的重点是最常见的边界层对流类型之一，并将包括水平对流角色如何与海风相互作用的研究。第三部分将利用大西洋快速增强气旋实验的数据研究海洋气旋形成的精细尺度细节。初步的雷达合成显示沿强暖锋形成的浅层中尺度环流。这种中尺度特征似乎是初期环流，当它与上层短波槽进入适当相位时，可以导致快速的气旋形成。＊＊＊

9422499 Wakimoto Physical forcing that occurs on small spatial and time scales (mesoscale) often determines the timing, location and severity of various weather phenomena. The Principal Investigator proposes to apply principals of mesoscale analysis to a variety of weather phenomena including tornadogenesis, study of convection in the boundary layer along what is termed horizontal convective roles, and to the study of oceanic cyclogenesis. The tornadogenesis study is focused on determining the physical factors that cause some severe thunderstorms to produce tornadoes while others do not. The Principal Investigator will participate in the second phase of the Verification of Origins of Tornadoes Experiment (VORTEX) as well as continue analysis of data collected during the first phase in the Spring of 1994. A unique aspect of this investigation is the first use of airborne Doppler data for the study of tornadogenesis. The study of horizontal convective roles is a continuation of analysis of data collected during the Convection and Precipitation/Electrification. This study is focused on one of the most common types of boundary layer convection and will include a study of how horizontal convective roles interact with the sea breeze. The third component will investigate the fine scale details of oceanic cyclogenesis using data from the Experiment on Rapidly Intensifying Cyclones over the Atlantic. Preliminary radar syntheses have revealed shallow mesoscale circulations that form along an intense warm front. This mesoscale feature appears to be the incipient circulation that can lead to rapid cyclogenesis when it comes into a proper phasing with an upper-level short wave trough. ***