The Structure of the Intertropical Convergence Zone and Its Role in Tropical Cyclogenesis

9523667弗兰克热带辐合带是全球大气环流的一个重要特征，具有复杂的天气尺度结构。根据这一奖项，首席研究员将研究西北太平洋ITCZ的三维结构、其可变性及其在热带气旋发生中的作用。我们将结合诊断分析和数值模拟来研究这些现象。诊断部分将使用综合分析和全球分析领域的案例研究，以确定与气旋发生有关的平均ITCZ结构和变化。这将由雷达探测数据的合成来补充，以进一步描绘与季风槽相关的温度、水汽和散度场。数值模拟将使用宾夕法尼亚州立大学/NCAR中尺度模式(MM5)的非静力版本。这一全物理模型将用于一系列初值实验，以评估外部环流对ITCZ结构和季风槽内热带气旋形成的影响。

9523667 Frank The Intertropical Convergence Zone (ITCZ) is a major feature of the global atmospheric circulation with complex synoptic-scale structure. Under this award, the principal investigator will examine the three dimensional structure of the northwestern Pacific ITCZ, its variability, and its role in tropical cyclogenesis. A combination of diagnostic analyses and numerical simulations will be used to study these phenomena. The diagnostic component will employ both composites and case studies of globally analyzed fields to determine the mean ITCZ structure and changes associated with cyclogenesis. This will be supplemented by composites of rawinsonde data to further delineate the temperature, moisture, and divergence fields associated with the monsoon trough. Numerical simulations will be performed with a non-hydrostatic version of the Penn State/NCAR Mesoscale Model (MM5). This full-physics model will be used in a series of initial value experiments to assess the effects of external circulations on the structure of the ITCZ and on the formation of tropical cyclones within the monsoon trough.