2004～2011年印度尼西亚贯穿流在望加锡海峡中的年际变化

Interannual variability of Indonesian throughflow in the Makassar Strait during 2004～2011

文章基于2004 年1 月-2006 年11 月的“国际努加登沙层结与输运”（international Nusantara stratification andtransport, INSTANT）计划以及2006 年11 月-2011 年7 月的“印度尼西亚贯穿流观测”（monitoring the Indonesianthroughflow, MITF）计划的实测数据, 从长时间序列研究印度尼西亚贯穿流的变化.在望加锡海峡中, 印度尼西亚贯穿流的周期信号分布非常丰富, 涵盖潮汐、季节内、季节和年际信号.对于季节变化, 东南季风期间温跃层深度上最大南向流速约为1.0m·s^-1, 而西北季风期间最大南向流速约为0.8m·s^-1.印度尼西亚贯穿流的年际变化与尼诺3.4 区指数（NINO3.4）呈正相关, 最大相关系数大约在NINO 3.4 前1~2 个月; 水深150m 以上, 印度尼西亚贯穿流与偶极子模态指数（dipole mode index, DMI）呈负相关, 200m 以下呈正相关, 在时间上较DMI 滞后约1-2 个月.季节变化的经验正交分解（empirical orthogonal function, EOF）前2 个模态方差的总贡献率为97%, 其中第-模态为65%, 第二模态为32%; 年际变化的EOF 前2 个模态的方差贡献率为90%, 其中第一模态为51%, 第二模态为39%.季节变化的第二模态和年际变化的第一模态表征赤道印度洋开尔文波模态, 该模态的空间结构在垂向会发生相位反转; 季节变化的第一模态和年际变化的第二模态表征赤道太平洋罗斯贝波（Rossby waves）的厄尔尼诺与南方涛动（El Nino and southern oscillation, ENSO）模态, 其垂向的空间结构变化比较一致.

Thanks to the INSTANT (international Nusantara stratification and transport) and MITF (monitoring the Indonesian throughflow) programs, more data became available for studying the Indonesian throughflow (ITF) through the Makassar Strait. The ITF in the Makassar Strait shows a broad range of activities, from tidal, intraseasonal, seasonal, to annual time scales. The maximum velocity in the Makassar Strait is thermocline intensified, at ?1.0 m?s?1 during the southeast monsoon and?0.8 m?s?1 during the northwest monsoon. The interannual variability of the ITF has a positive correlation with NINO 3.4, <br> leading NINO 3.4 by 1~2 months, while the ITF in the upper 150 m has a negative correlation with the dipole model index (DMI), but the ITF below 200 m has a positive correlation with the DMI, lagging DMI by 1~2 months. Empirical orthogonal function (EOF) analysis of seasonal variability reveals that the first two dominant modes account for 97%of the total variance, namely, the first and second modes accounted for 65% and 32% of the total variance, respectively. EOF of the interannual variability shows that the first mode accounts for 51%of the total variance, and the second, for 39%. The second mode of the seasonal variability and the first mode of the interannual variability are dominated by the intrusions of Kelvin waves from the tropical Indian Ocean. The first mode of the seasonal variability and the second mode of the interannual variability reflect ENSO modulation of Rossby waves from the tropical Pacific Ocean.