中文摘要：

回顾了世界各大洋和若干区域海洋的海平面、热含量、温盐结构及珊瑚变化等方面的主要成果,并对中国南海温盐结构的长期变化趋势进行了初步分析。结果表明,对全球增暖的响应,南海中层水盐度的长期变化表现出一定的淡化趋势。

英文摘要：

This paper reviews the observational results about the long-term variations of sea level, heat content, sea temperature, salinity and coral proxy, etc. in both the global ocean and regional basins. Moreover, the long-term variabilities of the temperature and salinity of the South China Sea （SCS） are analyzed. The results demonstrate that the sea water of the SCS intermediate layer become fresher significantly since the 1960s.