Current Structure of the Japan Sea Proper Water

1.作为国际科学研究方案(联合研究)的一部分，1995年夏天在日本海进行了一次全流域观测。观察的主要内容是系泊、CTD铸模和水样化学。观测提供了以下新的发现：(1)春季(3-4月)日本盆地中深层有强的正压洋流。日本盆地西部内陆最大流速超过30厘米/S。夏季和秋季，深水近乎停滞。(2)存在两个盐度最低层。浅水位于极锋以南的对马暖水，一直被称为日本海中间水。在日本盆地的所有站都发现了深盐度最低值。其潜在温度在0.1-0.15ﾟC之间，盐度在34.066-34.068psu之间。在深盐度最低层以下，溶解氧最小，这与北太平洋中层水下的垂直结构相似。这些结果表明，日本海固有水并不是过去所知的单一水团，而是至少由两个不同来源的水组成的。模拟的深部环流显示出与以前观测到的深部环流的主要特征一致的模式(Nitani，1972)。1996年2月在俄罗斯符拉迪沃斯托克举行了一次关于日本海物质和水循环的国际研讨会，会上介绍了该项目的所有成果以及相关的研究工作。会议还讨论了日本海国际合作研究的未来计划。

1. As part of the International Scientific Research Program (Joint Research), a basin-wide observation was conducted in the Sea of Japan in summer 1995. The main contents of the observation were moorings, CTD casts and water sampling for chemistry. The observation provided the following new findings :(1) Strong, barotropic currents occur in the mid and deep layrs of the Japan Basin in spring (March-April). The maximum current speed exceeded 30 cm/s in the interior region of the western Japan Basin. In summer and fall, the deep water is almost stagnant.(2) There are two salinity minimum layrs. The shallow one is located beneathe the Tsushima Warm Water south of the polar front, which has been known as the Japan Sea Intermediate Water. The deep salinity minimum was found at all stations in the Japan Basin. Its potential temperature was between 0.10-0.15ﾟC and salinity between 34.066-34.068psu. Below thedeep salinity minimum layr dissolved oxygen has its minimum, which is similar to the vertical sturucture beneath the North Pacific Intermediate Water. These results suggest that the Japan Sea Proper Water is not a single water mass as known in the past, but made of at least two waters of different sources.A fine resolution, primitive equation general circulation model was constructed. The simulated deep circulation shows a consistent pattern with the main features of the deep circulation as suggested from previous observations (Nitani, 1972).3. An international symposium on the material and water circulation in the Sea of Japan was held in Feb. 1996 at Vladivostok, Russia, in which all results of this project were presented together with related research work. Future plan of an international cooperative study on the Sea of Japan was also discussed.