Recent Change in the Intraseasonal Characteristics of Winter Temperature over South Korea

In this study, we analyzed the intraseasonal variability and change of winter temperature over South Korea using long-term observations. The lowest temperature in the wintertime, using daily mean, maximum, and minimum temperature data occurred on January 7th in the period of 2003~2012, while on January 22~25th in the past 30 years(1973~1982, 1983~1992, 1993~2002). Representative seven stations in South Korea also showed consistent result. The strengthening of Siberian High and weakening of Aleutian Low in recent 10 years are found to be closely related with the recent intraseasonal temperature change over South Korea. The baroclinic structure of upper-level low and lower-level high system near Korean peninsula provided good condition for vertical cold-air advection, which resulted in minimum temperature on late January in 1973~1982 and early January in 2003~2012 with strengthened low-level northerly flow.