A PRELIMENARY STUDY OF THE FORMATION OF YELLOW SEA COLD MASS AND ITS PROPERTIES

From the materials available for the analytical study, it is evident that the Yellow Sea cold water mass is in existence all the year round. In the winter, under the influence of the strong seasonal winds, surface water temperature rapidly falls, and the dry cold air also hastens evaporation of the sear water, thus resulting in the formation of a strong convection current. Moreover, the turbulence of the water enhances vertical mixing; consequently, there is formed in the offshore region a vertically uniform cold water mass, which is characterized by its low temperature and high salinity.In the summer surface sea water temperature is high and the pouring in of large quantities of fresh water from the continent results in the small density of the sea water. Owing to these factors, stability of the water layer has been greatly enhanced and the low temperature and high salinity characteristics of the bottom layer of the sea water have been well maintained.In the winter, the temperature of the cold water mass is about 30℃ to 8.2℃,and its salinity about 31.8‰ to 32.6‰.In the summer, its temperature is about 6.2℃ to 12.8℃,and. its salinity about 32.0‰ to 32.1‰.The Yellow Sea branch of the warm current coming from the south, the fresh water stream of the Yangtze River as well as the China Coastal Current of the Yellow Sea regien all have exerted their respective influence of varying degrees on the cold water mass. At present, our knowledge on its subject is very incomplete and further analytical studies are necessary.