동해 아극전선 남쪽에서 저염분 동해중층수의 계절변화

Abstract

Seasonal variation of the low salinity intermediate water (East Sea Intermediate Water, ESIW) in the south of subpolar front of the East/Japan Sea was studied by using historical oceanographic data observed by the Maizuru Marine Observatory (MMO) of Japan and the Korea Ocean Research and Development (KORDI). To obtain the water characteristics of the ESIW for isopycnal surfaces, depth, temperature and salinity of depth profile data were interpolated every 0.01 interval of potential density. And then the interpolated values were averaged at the same potential density. On the representative potential density of the ESIW (sigma theta=27.2), depth, potential temperature and salinity were analyzed. The salinity on the isopycnal surface of 27.2 sigma theta varied with seasonally in the south of the subpolar front (south of 38°N); high in winter and low in summer. However, near south of polar front the salinity was the lowest in spring and then increased with time. In the Ulleung Basin, the salinity was lower than the Yamato Basin and low in both of winter and summer. This implies that flow path and intrusion time of the ESIW into the two basins are different each other.