The regime shift in the early 1980s of spring precipitation in Korea

摘要

The change-point analysis demonstrates that there is a regime shift in the spring precipitation in Korea in 1980-1981. The total spring precipitation in the years post-1980 showed a distinct decrease compared to the years pre-1980. This phenomenon of reduced spring precipitation was particularly dominant in the southwestern regions of the Sobaek Mountain range in Korea. This phenomenon was also noticed in China and Japan, excluding south China. One of the major causes for this decrease in spring precipitation was the increased snow depth in the mid-latitude regions of continental East Asia. This resulted in a strengthened cold anticyclone over continental East Asia and a relatively weakened subtropical anticyclone over the western North Pacific, thus forcing a continuation of the typical winter pressure pattern of 'high-West and low-East' in East Asia from preceding winter into current spring. The strengthened northerlies from this zonal pressure pattern played a significant role in restricting the northern movement of the subtropical anticyclone and preventing the inflow of warm and humid air into Korea. Copyright (C) 2009 Royal Meteorological Society