摘要
分析了从 1 992年 1 0月到 1 996年 1 0月的TOPEX/POSEIDON卫星高度计和POCM模式输出的海平面高度 (SSH)资料、Levitus气候平均温盐资料、NCEP/NCAR再分析纬向流资料以及沿 1 37°E剖面的海流资料。分析结果表明 ,在年平均和月平均意义下 ,向东的副热带逆流 (STCC)位于 1 8°N～ 2 5°N、1 30°E～ 1 57°W间 1 50m以内的海洋上层 ,其强度大约为 0 .0 2～ 0 .0 4m/s,在西太平洋夏季 ( 7月 )最强 ,冬季 ( 1月 )最弱。在STCC以下 650m以上 ,还存在一支向西的流 ,流速也约为0 .0 2～ 0 .0 4m/s。在STCC区域内 ,SSH有明显的准 90天振荡。在天气时间尺度上 ,一些气旋和反气旋涡出现在STCC海域 ,使该海域的流在方向和强度上变化很大。
Sea Surface Height (SSH) data from TOPEX/POSEIDON mission and POCM output (October 1992-October 1996), temperature and salinity data from Levitus, reanalysis oceanic data from the National Centers for Environmental Prediction/National Center for Atmospheric Research and current data along 137 o E are analyzed in the present study. The results show that there is an eastward Subtropical Countercurrent (STCC) in the upper layer above 150 m in the scope of 18 o N～25 o N and 130 o E～157 o W in the North Pacific on the temporal scale of both annual mean and monthly mean, with the velocity of 0.02～0.04 m/s. STCC is the strongest in summer (July) and weakest in winter (January) in the western Pacific. Beneath STCC and above 650 m, there is a westward current at a speed of about 0.02～0.04 m/s. Remarkable quasi 90-day oscillation of the SSH appears in the STCC area. In zonal band centered at 20 o N from 120 o E to 150 o W, the ratio of the variance in the 80～109 day band and the total variance is larger than 0.3. On the synoptic scale, some anticyclonic and cyclonic eddies are present in the STCC area, which leads to a high variation of the direction and intensity of the zonal current in this area.
出处
《大气科学》
CSCD
北大核心
2000年第3期363-372,共10页
Chinese Journal of Atmospheric Sciences
基金
国家自然科学基金资助项目49976004
中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室开放课题!"北太平洋副热带逆流及其形成机制的数值模拟研究"
关键词
副热带逆流
气候特征
准90天振荡
北太平洋
subtropical countercurrent
climatic feature
quasi 90-day oscillation
Northern Pacific
