青岛冷水团强度的划分及其多年变化的分析

青岛冷水团位于青岛东南外海底层的相对低洼处。该水团于4月下旬显型,5月是它发展盛期,此后随着黄海沿岸水向北退缩,其位置渐往东移,并出现增盐趋势;6月以后,由于继续升温,便渐渐和南黄海冷水融为一体。 该水团尽管存在的时间较短,但每年均有其独立的生消规律,而且其温盐性质也相对稳定,对北上洄游的鱼类及山东南部近海对虾增

ANALYSIS OF THE STRENGTH AND YEARLY VARIATIONS OP QINGDAO COLD WATER-MASSES

In view of ocean thermodynamics, the author tried to combine three indexes, i. e. the lowest temperature, the area and the average temperature oi the all stations in the cold water sector, into one synthetic index for the relative intensity oi the cold water-masses. In this way, the consistency resulting from different single index may be overcome. According to the strength anomaly of the cold water-masses, yearly variations of the strength from 1960 to 1980 were analysed, and the results revealed the existence of 5-8 years periodicity for the strength of the cold water. Before 1973, yearly strength fluctuated much, but less there after. Therefore, in the 1960s and early 1970s, owing to the large difference of the strength for different years, the fishing periods and the fishing grounds of Shidao, Qingdao-Haiyang and Dalian-Qingdao-Shidao changed markedly yearly. In the middle and late 1970s, owing to the little variation of the strength of the cold water-masses, the fishing periods and fishing grounds between the two periods changed as well.