TOPEX/POSEIDON-derived space-time variations of the Kuroshio Current: applications of a gravimetric geoid and wavelet analysis
TOPEX/POSEIDON-derived space-time variations of the Kuroshio Current: applications of a gravimetric geoid and wavelet analysis
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DOI：
10.1046/j.1365-246x.2002.01811.x
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发表时间：
2002-12
影响因子：
2.8
通讯作者：
C. Hwang;R. Kao
中科院分区：
文献类型：
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作者：
C. Hwang;R. Kao
摘要 使用 TOPEX/POSEIDON (T/P) 高度计数据和重力大地水准面，我们得出了黑潮体积传输、轴速度、宽度以及台湾东北和东南部轴位置的 7 年时间序列。对于台湾东北部和东南部，平均体积输送分别为19和26 Sv，平均宽度分别为112和96 km，平均轴速度分别为50和82 cm s -1 。 T/P 导出的体积传输与原位结果非常吻合。 Drifter d21160 几乎穿过黑潮的 T/P 衍生轴。时间序列表现出季节内、半年、年度和年际变化，但由于季风、底部地形等因素，两个地点的频率特征不同。小波分析表明频率分量的幅度和相位随时间变化。几乎所有的时间序列中都存在两年一次的成分，并且可能是由大气的热带准两年一次的振荡所激发的。台湾东北部的输量与 ENSO 呈正相关（0.6），滞后 1 个月；台湾东南部的输量和速度与 ENSO 呈负相关（-0.6），滞后 9-10 个月。
SUMMARY Using TOPEX/POSEIDON (T/P) altimeter data and a gravimetric geoid, we derived 7-year time-series of Kuroshio’s volume transport, axis velocity, width and axis locations northeast and southeast of Taiwan. For northeastern and southeastern Taiwan, the mean volume transports are 19 and 26 Sv, the mean widths are 112 and 96 km and the mean axis velocities are 50 and 82 cm s −1 , respectively. The T/P-derived volume transports agree well with in situ result. Drifter d21160 almost passes through the T/P-derived axes of the Kuroshio. The time-series show intraseasonal, semi-annual, annual and interannual variations but the frequency characteristics at the two locations are different owing to monsoon, bottom topography and other factors. Wavelet analyses show that the amplitudes and phases of the frequency components vary with time. A biennial component is found in almost all time-series and may be excited by the tropical quasi-biennial oscillation of the atmosphere. The volume transport northeast of Taiwan has a positive correlation (0.6) with ENSO with a 1-month lag, and both the volume transport and velocity southeast of Taiwan have a negative correlation (−0.6) with ENSO with a 9‐ 10 months lead.