한국 남동연안 용승해역에서 수온변동

Abstract

The southeastern coast of Korean Peninsula is the northwestern part of the western channel of Korea Strait. While the mixed layer reaches near the seabed in winter, strong thermocline is developed in summer. The wind is changed by seasonally because of strong effect of monsoon in this area. The wind blows from the northwest in winter and from the southwest in summer. The direction of the coastline is mainly from southwest to northeast. Therefore, the upwelling is frequently occurred in summer in the southeast coast of Korea. The upwelling provides rich nutrients from the bottom layer for the surface layer in which nutrients are exhausted because of strong thermocline. So the upwelling is important in ecosystem in the Ulleung Basin.To study long term variations of the upwelling in the southeast coast of Korea, the wind at Pusan and the surface temperature at Ulgi and Gampo for 41 years form 1967 to 2007 are analyzed. Upwelling favorable southwest wind which is parallel to the southeast coastline is calculated by coordinate transform to clockwise 22.5 degrees form the north. While the frequency of southwest wind that blew more than 3 days was increased, accumulated wind for southwest wind that blew 3 days was decreased during summer (from May to September). Upwelling events were determined by the drop of surface