Although the SST cooling events around the Lesser Sunda Islands (LSIs), which contribute to the seasonal variation of SST in the southern Indonesian Seas, are thought to be controlled by tidal mixing, the distribution of tidal mixing was highly idealized in previous studies. This study reinvestigates the mechanisms of such SST cooling events using MITgcm, which incorporates the realistic distribution of tidal mixing. The observed SST variability is well reproduced in the numerical experiment; SST is largely reduced along the northern (or southern) coast of the LSIs during austral summer (or winter). Particle tracking suggests that the narrow tidal straits between the LSIs, where well‐mixed waters are produced by vigorous tidal mixing, play a key role in controlling the SST cooling. During austral summer, the cold SST signal of well‐mixed waters propagates both northward and southward from the narrow straits as baroclinic Kelvin waves. On the northern side of the LSIs, in particular, coastal upwelling caused by the northwest monsoon raises the background thermocline, which affects the propagation of baroclinic Kelvin waves such that the accompanying cold SST signal becomes much enhanced compared with that on the southern side of the LSIs. During austral winter, in contrast, the Ekman transport enhances southward through‐strait flow so that baroclinic Kelvin waves can propagate only southward affecting the SST on the southern side of the LSIs. This demonstrates the importance of the combined effects of tidal mixing in narrow straits and the Ekman transport on the SST cooling in the southern Indonesian Seas.

中文翻译：

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印尼海域海潮混合和埃克曼输运对海表温度降温的综合影响

尽管人们认为小Sun达群岛（LSIs）附近的SST降温事件是由潮汐混合控制的，这是造成印度尼西亚南部海域SST季节性变化的原因，但在以前的研究中，潮汐混合的分布是高度理想的。这项研究使用MITgcm重新研究了此类SST降温事件的机制，该机制结合了潮汐混合的实际分布。数值实验很好地再现了观测到的海温变化。在南方夏季（或冬季），LSI北部（或南部）沿岸的SST大大降低。粒子跟踪表明，LSI之间的狭窄海峡海峡（通过剧烈的潮汐混合而产生充分混合的水）在控制SST冷却中起着关键作用。在南方的夏季，混合水域的冷SST信号以斜压开尔文波从狭窄海峡向北和向南传播。特别是在LSI的北侧，由西北季风引起的沿海上升上升了背景温跃层，这影响了斜压开尔文波的传播，因此相伴的冷SST信号相比于南侧的SST信号大大增强了。 LSI。相反，在南方冬季，Ekman运移使海峡两岸向南流动增加，因此斜压开尔文波只能向南传播，从而影响了LSIs南侧的海温。这证明了狭窄海峡的潮汐混合和埃克曼运输对印尼南部海域海表温度降温共同作用的重要性。