With the nonhydrostatic axisymmetric cloud‐resolving model CM1, two sets of ensemble runs are conducted to study the influence of initial vortex depth on the early development of an idealized tropical cyclone (TC). It is found that with the shallow initial vortex, the intensification rate (IR) is smaller and the TC takes a longer time to reach a state of slantwise moist neutrality. These behaviors are primarily ascribed to the less active convection in the shallow case. In contrast to the deep initial vortex, the shallow initial vortex is characterized by a more stable stratification in the lower troposphere and a smaller gradient of angular momentum (M) in the mid‐to‐upper troposphere. The former tends to hinder the occurrence of deep convection in the TC while the latter makes it difficult to intensify the mid‐to‐upper level vortex and to establish a deep vortex. Thus, deep convection bursts intermittently in the early developing stage of the TC originating from the shallow vortex. During the periods of inactive convection, the TC weakens by the decline of M source associated with reduced horizontal advection, which is overwhelmed by sinks of M from moderately decreased vertical advection and nearly‐constant dissipation term. Therefore, the IR of the TC is smaller in the early developing stage and the development of TC from the shallow vortex usually needs a longer time to build the steady deep secondary circulation favorable for more rapid intensification.

中文翻译：

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初始涡垂直结构对轴对称热带气旋早期发育的影响

使用非静力轴对称云解析模型CM1，进行了两套合奏，以研究初始涡旋深度对理想热带气旋（TC）早期发展的影响。发现初始涡流较浅时，增强率（IR）较小，TC需要较长时间才能达到偏湿的中性状态。这些行为主要归因于浅层情况下较不活跃的对流。与较深的初始涡流相反，较浅的初始涡流的特征是在对流层下部的分层更加稳定，并且角动量的梯度较小（M）在对流层中上层。前者倾向于阻碍TC中深对流的发生，而后者则使得难以加强中上水平涡旋并建立深涡旋。因此，在对流的早期发展阶段，深对流间歇性地爆发，源于浅涡。在非活动对流的期间，TC削弱由衰落中号源具有降低水平平流相关联，这是由汇淹没中号来自垂直对流的适度下降和几乎恒定的耗散期。因此，TC的IR在发展的早期阶段较小，TC从浅涡旋的发育通常需要较长的时间来建立稳定的深层二次循环，这有利于更迅速地强化。