【摘要】 初步分析中国科学院南海海洋研究所《实验3号》科学考察船在TOGA—COARE IOP连续三个航次中部分CTD和ADCP原始观测资料指出:90-210m间大于35的盐度极值除存在准日周期变化外,在量值上还存在约73d的周期变化。但受资料长度的限制,目前尚无法确定上述周期是否属于稳定周期。在上述深度范围内亦存在较低盐度和温度水体侵入现象,其强度存在10—15d的周期变化。等温线和等密度线常出现振幅达10m以上,周期约3d的振荡,而且有时表现出次中尺度涡(submesoscale eddy)及涡旋链特征。比较风、SST、混合层深度间的关系时发现,风强度和大风维持时间对SST和混合层深度的影响很大,如西风暴发过程可使平均SST降低0.5℃左右,使平均混合层深度加深8m以上。分析西风暴发过程及西风暴发后洋流铅垂变化和洋流随时间变化发现,西风暴发过程导致79m以浅深度上的东向射流,且19m深处流动随时间顺时针改向,79m深处流动随时间逆时针方向改向。更多还原

【Abstract】 This paper analyses the CTD and ADCP data collected by "Shiyan 3" during the TOGA COARE IOP. The results show that there is, between 90-210m, a higher salinity layer in which the maximum of salinity oscillates at the periods of quasi - one day and 73 days (the existence of the periods of 73 days need to be further comfirmed by longer data set), and in which there is also an intrusion of the lower salinity and temperature water mass and its strength varies at a 10-15 day period. It is found from the time- depth diagram of temperature and density that the isotherm and the isopycnal, sometimes, present the characteristics of oscillation with a 10m amplitude and 3 day period as well as the characteristics of submesoscale eddy or eddy chains. Comparing the time series of the wind with the thickness of the mixed layer, we can find that the variations of SST depend, to a great extent, on the strength and the duration of wind. For example, the westerly wind burst can cause the mean SST to decrease by about 0. 5 ℃ and causes the mean thickness of the mixed layer to deepen more than 8m. The results also show that after 6 days of the westerly wind a eastward surface jet was formed and the jet mainly appeared at a depth shallower than 80m, and during the westerly wind burst and after it, the current changed direction clockwise at 19m and anticlockwise at 79m.更多还原