初夏의 旱魃과 降水量의 經年變動

Abstract

Korean Peninsula which belongs to the East Asian monsoon climatic region has a plenty of rainfall comparatively. However, the interannual variation and seasonal fluctuation of the precipitation is extremely irregular. Especially, in early summer the severe droughts appear by the year. So the agricultural cultivation recieves the large damage by the case. In this paper, the year climatological and synoptical analyses for the droughts and the precipitation variation were carried out.

The height anomaly pettern of 500mb surface in dry year is shown reversely to that of wet year. In dry early summer, the strong positive height anomaly appears zonally from Tibet Plateau to Ohotzk Sea. and the negative height anomally is zonally appeared in the lower latitude. And the simultaneous correlation between the 500mb surface height and the climatic elements has also the reverse pattern in dry and wet year. According to the results of power spectrum analysis from 1916 to 1978 have the peak density at 12 and 6 years period.

Finally, the areal precipitation in May has a striking resemblance to the interannual trend of zonal index of 500mb surface from 1945 to 1975.