摘要
利用2000年夏季和2001年冬季渤海两次CTD资料,系统分析了渤海冬、夏季温盐密度的分布特征,并揭示了渤海现有的水文特征与以往研究结果相比存在一些新现象,表现在:夏季在渤海海峡、辽东湾口和渤海湾口中部中、下层存在3个低温中心,在渤海中部则出现1个上下均匀一致的高温中心;冬季等温线以渤海海峡暖中心向西和向北两个方向伸入渤海,而从秦皇岛外海有一冷水舌向东南方向伸展,在渤海中部海域形成"马鞍状"等温线结构.冬、夏季渤海盐度比以往有显著升高,并明显高于北黄海西部,盐度分布势态表现为渤海湾高盐,渤海海峡低盐特征.密度分布表明:夏季渤海的密度流较强,并在中部可能存在多个密度流涡环;冬季渤海"马鞍状"温盐结构反映其环流结构要比以往研究结果复杂得多,黄海暖流(余脉)在渤海存在分支现象.利用模式对其进行密度流的诊断模拟,结果和实测温盐场符合较好.
Using the two CTD data of the summertime in 2000 and wintertime in 2001 in the Bohai Sea, the temperature, salinity and density distributional characteristics of the wintertime and summertime in the Bohai Sea are analysed systemically and it is revealed that the current hydrologic characteristics of the Bohai Sea have some new phenomena compared with the previous research results. In summer there are three low-temperature centers in the middle-layer and underlayer of the middle parts of the Bohai Straits, the Liaodong Gulf-mouth and the Bohai Gulf-mouth but there is a uniform high-temperature center in the middle Bohai Sea. In winter the isotherms extend westward and northward to the Bohai Sea from the warm core of the Bohai Straits and the cold water tongue off the Qinhuangdao spreads southeastward out, so the saddle-like isotherm pattern is formed in the middle Bohai Sea. The salinity in the Bohai Sea in summer and winter rises significantly compared with the previous results and is higher than the northwestern Huanghai Sea. The salinity distribution characteristics are the high-salinity in the Bohai Bay and the low-salinity in the Bohai Straits. The density distribution shows that in summer there is a large cyclonic density circulation in the Bohai Sea and it is likely to exist some density current eddies in the middle part. In winter the saddle-like pattern of the Bohai Sea temperature and salinity shows that the circulation structure is much complexer than the previous research results. The Huanghai Sea Warm Current (extension) has branches in the Bohai Sea. The model diagnostic results of the thermohaline residual currents accord well with the observed data.
出处
《海洋学报》
CAS
CSCD
北大核心
2004年第1期14-24,共11页
基金
教育部科技项目(0080)
重点基础研究规划项目(G1999043804)
自然科学基金项目(40076001).
关键词
渤海
水文特征
温度
盐度
Bohai Sea
temperature
salinity
hydrologic characteristics