This study examines atmospheric structures causing convective development in the events of cloud cluster (CC) over the Korean peninsula using the analysis and forecast data of National Centers for Environmental Prediction (NCEP) climate forecast system reanalysis (CFSR) and observation data. Two CC types—CCs associated with meso-α-scale lows (CCMLs) and mesoscale troughs (CCMTs)—were investigated. The common atmospheric structure for convective development in CC events is comprised of i) a strong southwesterly band (SWB; a region with southwesterly wind speeds >12.5 m s⁻¹) in the lower troposphere upstream of CCs with a mesoscale convergence zone in its exit area, ii) a layer of high-θ_e air in the lower troposphere near the surface extending from the southwest to SWB exit, iii) elevated height of maximum θ_e in the lower troposphere near and over the convergence zone, above which a convectively unstable layer exists. Generality of the above-described structure has been demonstrated via examination of composite fields. SWB plays a major role in producing the structure for convective development in CC events over the Korean peninsula mainly through i) advection of high-θ_e air from the southwest, and ii) significant horizontal convergence in the exit area, which can facilitate convection initiation. The two types of CC show notable differences in atmospheric structure across the boundary between high-θ_e air from the southwest and low-θ_e air in the northeast and in the mode of high-θ_e air transport to the region of convective development. The boundary is generally tilted northeastward with height for CCML cases, whereas it is nearly vertical for the majority of CCMT cases. This study indicates that, despite the above-mentioned differences, convective developments in both CC types can be considered as elevated convection that occurs as air parcels in an elevated layer of convective instability are lifted by upward motion in the convergence zone. For both types of CC, differential θ_e advection plays the key role for the occurrence of elevated layer of convective instability. And θ_e front in CCML events indicates the presence of elevated convective instability above it and the possibility of elevated convection provided that a lifting mechanism is available.

这项研究使用国家环境预测中心（NCEP）气候预测系统再分析（CFSR）的分析和预报数据以及观测数据，研究了朝鲜半岛云团（CC）事件中引起对流发展的大气结构。研究了两种CC类型-与中α尺度低点（CCML）和中尺度低谷（CCMT）相关的CC。CC事件中对流发展的常见大气结构包括：i）CCs上游对流层低层的强西南风带（SWB；西南风速> 12.5 m s ^-1的区域），其出口区域有中等规模的汇聚带，ii）高_θe层低对流层中从西南向西南向西南方向延伸的地表附近的对流层中的空气，iii）对流层附近和上方的对流层中最大对流层最大_θe的高度升高，在其上方存在对流不稳定层。上述结构的一般性已经通过研究复合领域得到了证明。SWB在产生朝鲜半岛CC事件中对流发展的结构中起主要作用，主要是通过以下方式：i）来自西南的高_θe空气对流，以及ii）出口区域明显的水平会聚，这可以促进对流的启动。这两种类型的CC的显示在大气结构跨越边界高-θ之间的显着差异_Ë空气从西南和低θ_Ë在东北和在高θ的模式空中_ë空运到对流发展的区域中。对于CCML案例，边界通常向东北倾斜，并具有高度，而对于大多数CCMT案例，边界几乎是垂直的。这项研究表明，尽管存在上述差异，但两种CC类型的对流发展都可以看作是对流发展，这是由于会聚区中向上运动引起的对流不稳定性升高层中的空气包裹而引起的。对于两种类型的CC，微分_θe对流在对流不稳定性升高层的发生中起关键作用。和_θe CCML事件中的“前”表明存在高于其的对流不稳定性，并且存在对流不稳定的可能性，前提是可以使用举升机构。