1991년 이후 한반도 8월 강수의 증가와 원인

Abstract

In the comparison of time series of AWRI between the recent 15 years and past 15 years, the dry period between the summer Changma and the autumn Changma has been shortened by increase of August precipitation. Generally the summer rain and heavy rain in the Korean peninsula occur in the Changma period. However the tendency is clear that frequently happened in August even after the Changma period in the recent 15 years. The high was developed along with the increase of the geopotential height of surrounding area from Lake Baikal in the heavy rain years, which caused the increase of August precipitation. Also, the high was developed in the East china Sea and the North-West Pacific Ocean especially in the lower levels. Therefore there is a development of low in the Korean peninsula that is placed in the center. There was an increase of water vapor inflow to the Korean peninsula along the edge of the high development area of East china Sea and the North-West Pacific Ocean. It seems that it was arose from the changes of large atmospheric circulation effected by the increase of the continental temperature and sea surface temperature. There is an increase of precipitation and Outgoing longwave radiation spreading out to the Korean peninsula from the Bangladesh through the Yangtze river, North Honshu area, and Hong Kong from Korean peninsula in the heavy rain years. These areas are covered by developed low and they are placed the edges of North Pacific High.In the wide range, there is an extension of North Pacific High to the west and Tibetan high was weakened. As a result of the analysis on the anomaly of various factors, the speed of the omega and wind speed in the low level and high level was increased. And there was an increase of south-west inflow and the water vapor inflow in the west sea.