Cluster analysis of Tropical Cyclones making landfall on the Korean Peninsula

Cluster analysis has been performed on the tracks of 51 Tropical Cyclones (TCs) that made landfallon the Korean Peninsula (KP) for the period of 1951--2004. The classification technique of the landfallingtracks used in this study was the fuzzy clustering method (FCM) and the resultant silhouette coefficientsuggested four clusters as an optimal cluster number. Most TCs of Cluster 2 and Cluster 3 (C-23) tendedto pass through mainland China before landfall, but those of Cluster 1 and Cluster 4 (C-14) tended tomostly land after moving northward from the East China Sea (ECS) without passing over mainland China.The TC landfalling frequency of C-14 has begun to clearly increase since the late 1980s, particularlythe maximum landfalling frequency in the early 2000s set a record for the 54-year analysis period. Theridge axis of the western North Pacific high (WNPH) of C-23 bends more equatorward than that of C-14,so that the monsoon trough of C-23 is located more equatorward than that of C-14. As a consequence,most TCs of C-23 tend to recurve inland of China, but over the ECS for C-14.