南爪哇流的季节内变化

Intraseasonal Variations of the South Java Current

利用锚定潜标的观测数据,结合再分析资料和卫星观测资料,采用最大熵谱分析,对南爪哇流的时间变率进行了分析。结果显示,南爪哇流存在非常显著的季节内变化,分析表明南爪哇流的季节内变化与热带印度洋的大气季节内振荡强迫有着密切的联系。伴随大气季节内振荡的低空纬向风激发了向东传播的赤道Kelvin波,它到达印度洋东边界后产生了一支向南传播的沿岸Kelvin波,这支沿岸Kelvin波继续沿着苏门答腊岛和爪哇岛向南传播,从而引起南爪哇流的季节内变化。

Based on the datasets from mooring, reanalyzing and satellite, the time-scales of the South Java Current is analyzed by means of the maximum entropy spectral analysis. The results show that the South Java Current has a significant intraseasonal variability and such a change is closely related to the Madden- Julian Oscillation （MJO） present in the tropical Indian Ocean. After the eastward equatorial Kelvin wave which is excited by a low altitude zonal wind accompanying the MJO arrives at the eastern boundary of the Indian Ocean, a coastal Kelvin wave moving southward can be generated. This coastal Kelvin wavegoes further southward along the Sumatra and the Java islands, thus causing the intraseasonal variation of the South Java Current.