동해남서부해역에서 냉수의 경년변동성

Abstract

Year-to-year variability of cold water in the Ulleung Basin of the East/Japan Sea is investigated based on historical hydrographic data. Three different types of cold water are distinguishable: northern and southern cold water along the east coast of Korea and one offshore in the southern Ulleung Basin. In summer their distributions show three characteristic patterns. In general, northern cold water that has been noticed in the northwestern region of the Ulleung Basin near the east coast of Korea extends offshore and southward along the coast in summer. However, its offshore, as well as southward, expansion varies largely from year to year. Southern cold water near the east coast of Korea around 36°N also varies from year to year. Southern cold water combines with the northern cold water into a large mass in some years but is isolated from the northern cold water due to the warm water mass associated with the Ulleung warm eddy. The relationships of the bottom cold water around the Korea Strait with these other cold water features are examined. The bottom cold water in the western region of the Korea Strait is probably related tothe expansion of the cold water appearing along the east coast of Korea, while that in the central region of the Korea Strait is related to the southward expansion of offshore cold water.