Role of MCC (Mesoscale Cloud Clusters) on the Large Spatial and Temporal Variability of Rainfall over Southwest Korea in Summer 2003

摘要

The In East Asia, mesoscale corrective cloud systems (clusters) develop over the continental part of China and the Yellow Sea in summer and propagate to the east toward the Korean peninsula and Japan Islands along the East Asian frontal zone. The Mesoscale Cloud Clusters (hereafter, MCCs) frequently observed in the East Asian frontal zone affect temporal and spatial variations of rainfall according to their dimension and lifetime. A number of previous studies focused on the appearance characteristics, diurnal variation, evolution process and structure and behavior of the MCCs in summer season (Iwasaki and Takeda, 1993; Kato et al., 1995; Sakamoto, 2003; Ninomiya et al., 2003). Also, it has been found that the development and propagation of MCCs largely affects the rainfall characteristics. However, the role of MCCs in meso-b-scale rainfall distribution has not been well understood. In the summer of 2003, Korea experienced frequent rainfall events. The number of days with rainfall during summer (June to August) is 47.2 days, which give the first rank in the number of days with rainfall during recent 30 summers. In this study, rainfall characteristics in frequent rainfall events over southwest Korea during 15-day period of 1 July to 15 July in 2003 are investigated and then a possible cause of frequent rainfall records is suggested from the point of view of the development and propagation of MCCs developing over the Yellow Sea.