TWO BETA SPIRALS IN THE WESTERN BOUNDARY REGION OF THE PACIFIC

Beta spiral technique can be used to determine the three dimensional velocity field , usually in the open ocean , as functions of depth at a single location. This work is aimed at applying the method to the lower layers in the western boundary area of the Pacific at two locations covered by 5 CTD stations each , and then using the results to study the vertical structure of the western boundary current in the Pacific .     

Long-term variabilities of thermodynamic structure of the East China Sea Cold Eddy in summer

Based on more than 30 years observed sectional temperature data since the 1960s, and compared with multi-year wind and Changjiang (Yangtze) River discharge data, spatial-temporal variations of the East China Sea Cold Eddy (ECSCE) in summer was analyzed in relationship to ocean circulation and local atmospheric circulation. Empirical Orthogonal Function (EOF) and Singular Value Decomposition (SVD) analyseswere applied to this study. The results show that: l) The ECSCE in summer possesses significant interannual variabilities, which are directly associated with oceanic and atmospheric circulation anomaly. Main fluctuations demonstrate their falling in basically with E1 Nino events (interannual) and interdecadal variability. 2) The ECSCE in summer is closely related to the variation of the Yellow Sea Warm Current (YSWC) and the Changjiang River discharge. The stronger the YSWC, the more intensive the ECSCE with its center shifting westward,and vice versa. However, a negative correlation between the Changjiang River discharge and the ECSCE strength is shown. The ECSCE was strengthened after the abrupt global climate change affected by the interdecadal variation of the YSWC. 3) SVD analysis suggested a high correlation between the variation of the ECSCE in summer and the anomalous cyclonic atmospheric circulation over the ECS. Intensification of the cyclonic wind strengthens the ECSCE, and vice versa. 4) The cyclonic atmospheric circulation has dominant influence on the interannual variation of the ECSCE, and the influence of the ocean circulation takes the second in. The ECSCE was usually stronger in E1 Nifio years affected by strong cyclonic circulation in the atmosphere. The variation in strength of the ECSCE resulted from the joint effect of both oceanic and atmospheric circulation.     

南海夏季风爆发与西太平洋暖池区热含量及对流异常

利用1955～1998年逐月的上层海洋热含量资料和NCEP/NCAR再分析资料,研究了南海夏季风爆发与热带西太平洋暖池区热含量异常的关系,并对影响过程进行了探讨.结果表明:(1)热带西太平洋暖池区是热带上层海洋热含量变化最大的区域,暖池区的热含量的变化与ENSO关系密切,是ENSO循环的重要组成部分,也是影响南海夏季风爆发最明显的地区.(2)南海夏季风爆发与前期(特别是前期冬、春季)暖池热状态的变化有密切关系,当前期暖池热含量高时,南海夏季风爆发早,反之爆发晚,这与由暖池变化所产生的上空大气的对流活动密切相关;4月暖池区热含量高(低)是预报南海夏季风爆发早(晚)的一个很好指标.(3)西太平洋暖池区热含量正异常时,辐散中心位于南海—西太平洋,对流强,西太副高弱且位置偏东,季风环流(印度洋纬向环流和经向环流)和Walker环流为正距平环流;正距平的季风环流有利于低空西到西南气流的加强,南海夏季风爆发早,反之爆发晚.由暖池变化所引起的大尺度季风环流和Walker环流的异常变化可能是影响南海夏季风爆发的一个重要动力机制.     

基于漂流浮标观测分析日本福岛以东表层海洋物质的散播轨迹

认识海洋中的物质如何散播对于理解海洋环境变化和人类活动污染在海洋中的扩散过程具有非常重要的意义。利用历史海表漂流浮标观测数据,对日本福岛以东海域的表层物质散播轨迹进行了拉格朗日示踪分析和观测模拟试验研究。结果发现,福岛以东海域海表浮标的散播路径主要分为东、南两支,其中速度较快的东支为主要通道,沿黑潮延伸体汇入北太平洋流,最短用时大约22个月即可到达北美西海岸;南支则沿黑潮延伸体以南的大范围南向流向西南方向运移,速度较慢且明显受涡旋活动影响,最快大约5个月即可到达吕宋海峡和中国台湾以东海域,进而进入南海和东海等中国近海海域。通过开展观测模拟试验,发现海表浮标散播的概率密度分布呈现以福岛附近海域为核心、向西南和正东方向递减扩展的形态,其中,到达中国近海的浮标主要通过吕宋海峡进入。文章详细讨论了研究结果的局限性、不足之处,以及因基于大量现场观测而具备的重要参考价值。     

我国的海洋通量研究

我国的海洋通量研究海洋通量（ＯｃｅａｎＦｌｕｘ）是８０年代中期提出筹划、９０年代实施的国际海洋科学前沿研究中的一个重要领域。全球海洋通量联合研究（ＪＧＯＦＳ：１９９０～２０００）是为此而设置的研究计划，为全球变化研究项目“国际地圈生物圈计划”（ＩＧＢ...     

哈马黑拉涡旋的季节变异研究

利用1992年1月～2006年11月期间的ECCO2海洋同化数据资料,研究了海洋上层50m平均的哈马黑拉涡旋的季节变异特征。结果表明,哈马黑拉涡旋在5月开始出现,7月达到最强,3月和4月消失,这主要取决于新几内亚沿岸流的季节变化。新几内亚沿岸流4～11月为西北向,从12月到次年的2月为东南向。随着西北向新几内亚沿岸流的增强,哈马黑拉涡旋开始出现并增强。而随着西北向新几内亚沿岸流的减弱和反向,哈马黑拉涡旋减弱并消失。同时棉兰老海流在夏季的增强也有利于哈马黑拉涡旋增强。旨在研究哈马黑拉涡旋的季节变异特征及其影响因子,为进一步探讨其垂向结构、年际变异等时空变化特征和该区域的环流特征提供研究基础。     

A THOUGHT ON THE ROLE OF WESTERN PACIFIC OCEAN CIRCULATION IN CLIMATE CHANGE IN SOUTHEAST CHINA

Regarding climate change in China, ordinary people, even meteorologists, would think the cold waves from Siberia dominate winter temperature in southeast China. As oceanographers, however, we must know the role of ocean circulation in climate change. This text briefly discusses how important is the role of the Western Pacific Ocean circulation in climate change in southeast China on the basis of CTD data gathered by the R/V Science 1 in the western Pacific in September and October, 1986 and 1987 respectively , and statistical air temperature data in southeast China.     

中国的海岸带陆海相互作用(LOICZ)研究

中国的海岸带陆海相互作用（ＬＯＩＣＺ）研究刘瑞玉胡敦欣（中国科学院海洋研究所，青岛，２６６０７１）海岸带陆海相互作用研究处于有关学科领域发展的前缘，又是自然科学多学科交叉及其与社会科学的交叉点，在学科发展上和在近海持续开发发展上都有重要意义。中国很重...     

137°经向断面温、盐度的年际变异

系统地分析了137°E断面温、盐度的多年变化,主要结果为:(1)137°E断面100m层温度,在低纬度海域于某些年份出现异常低温,此现象可能与厄尔尼诺事件有关;指出棉兰老冷涡的存在是造成该断面于6°～8°N附近出现低温的主要原因。(2)厄尔尼诺期间,冬季137°E断面上28℃等温线所在纬度小于其多年平均值。(3)冬季137°E断面上次表层高盐水可划分为强型、次强型、中等型和弱型4种类型。     

A STATISTICAL STUDY ON RELATIONSHIP OF EL NINO EVENTS TO THE HYDROGRAPHY ALONG 137°E IN WINTER

Principal component analysis (PCA) as used by meteorologists and oceanographers is a powerful tool for analysis of the spatial and temporal variability of physical fields.This study was aimed at applying "quasi-local PCA for singular factor" to make the cumulative percentage for the first principal component as great as possible, so that a multi-dimensional problem can be reduced to a single-dimensional one, and then stepwise regression analysis can be used to parameterize the relationship between El Nino events and the hydrographic factor anomalies along 137 癊 in winter.The results show that the salinity anomalies on 30 m level, the sigmat on 250 m level, and the temperature on 300 m level at 8 癗 are most closely related with El Nino events because of thermocline movement caused by enhanced upwelling in this area during El Nino years.