济州岛西南海域水团组成的周年变化

摘要

The southwestern sea of Cheju Island is influenced by many different water masses.Water mass analysis can help to understand local hydrological characteristics and fishery resources. Based on the simulation of Nucleus for European Modeling of the Ocean (NEMO) and the multi-concentration mixing proportion scheme, the spatial distribution and the mixing ratio of different water masses in this area, along with their volume percentage and annual variation were quantita-tively defined. From January to April, two water masses dominated:Shelf mixed water of the East China Sea (EM) and Ku-roshio water of the East China Sea (KE),and the latter showed dominant position,as its volume percentage was always above 50%.From May to July, four water masses existed, including Surface water of the East China Sea (ES),Bottom cold water of the East China Sea (BCW),Kuroshio surface water (KES),and Kuroshio subsurface water (KEB),while the last kind dominated the area with its volume percentage around 45%.From August to December,BCW disappeared, and the other three water masses still existed. During this period,KES was the dominant water mass with its volume percentage mostly above 50%, but KEB dominated the bottom with its power reaching the peak in August,and becoming weaker and weaker in the following months.%济州岛西南海域被认为是多种水团的“集散区”，水团分析有助于理解当地的水文特征以及海洋渔业资源的分布和变动。基于欧洲海洋核心模型(NEMO)，利用浓度混合分析方法，定量地给出了该海域各水团混合比例的空间分布以及体积分数，其水团空间组成的周年变化：1—4月2个水团，东西两侧分别为黑潮上层水和东海陆架混合水，黑潮上层水占有明显优势，体积始终在50%，以上；5—7月4个水团，西侧表层为东海表层水，底层为东海底层冷水，东侧表层为黑潮表层水，底层为黑潮次表层水，黑潮次表层水占优势，体积一直在45%，左右；8—12月3个水团，东海底层冷水消失，其余3个继续存在，黑潮表层水占优势，体积基本都在50%，以上，黑潮次表层水主导底层，势力8月最强，以后逐月变弱。