Influence of mesoscale eddies on Indonesian throughflow dynamics in the Sulawesi Sea simulated in an ocean general circulation model

IF 3.9 3区地球科学 Q1 OCEANOGRAPHY

Progress in Oceanography Pub Date : 2026-06-01 Epub Date: 2026-05-29 DOI:10.1016/j.pocean.2026.103769

Fuad Azminuddin , Adi Purwandana , Aloysius Bagyo Widagdo , Mardi Wibowo , Raden Dwi Susanto

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引用次数: 0

Abstract

The Sulawesi Sea is the key entrance of the Indonesian Throughflow (ITF), connecting the western Pacific Ocean to the Indonesian seas. Mesoscale eddies are frequently observed in this semi-enclosed basin; however their interaction with the ITF remains largely unexplored. Using a high-resolution ocean reanalysis for the period 1993–2020, this study examines the distribution, variability, and influence of mesoscale eddies on ITF circulation in the Sulawesi Sea.

The basin circulation is characterized by ITF from the Pacific toward the Makassar Strait, with two secondary pathways: the Sulu-to-Sulawesi Sea inflow (SSI) and the Sulawesi-Maluku Sea exchange flow (SME). We identified three quasi-persistent mesoscale eddies: an anticyclonic eddy in the northern basin (NSAE) and two cyclonic eddies in the southwestern (WSCE) and southeastern (ESCE) regions. WSCE exhibits the most persistent occurrence (60%), whereas ESCE has the largest mean length scale (∼118 km).

Cyclonic eddies intensify during weakened ITF and enhanced SSI and SME, whereas anticyclonic variability is closely associated with strong ITF inflow. Composite and lagged analyses indicate that cyclonic eddies recirculate and divert a portion of ITF waters toward the Maluku Sea, thereby reducing effective throughflow to the Makassar Strait. Seasonally, ITF strengthens in boreal summer and weakens in early winter, opposite to eddy activity, while interannually, ITF transport is enhanced (reduced) during La Niña (El Niño), resulting in suppressed (enhanced) eddy energy. The findings highlight a two-way interaction between mesoscale eddies and the ITF, emphasizing the critical role of local eddy dynamics in regulating ITF pathways at this Indo-Pacific gateway.

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海洋环流模式模拟中尺度涡旋对苏拉威西海印度尼西亚通流动力学的影响

苏拉威西海是印度尼西亚通流（ITF）的关键入口，连接西太平洋和印度尼西亚海。中尺度涡旋在半封闭盆地中频繁出现；然而，他们与ITF的互动在很大程度上仍未被探索。利用1993-2020年期间的高分辨率海洋再分析，本研究考察了苏拉威西海中尺度涡旋对ITF环流的分布、变率和影响。盆地环流以太平洋向望加锡海峡的ITF为特征，有苏拉威西-苏拉威西海流入（SSI）和苏拉威西-马鲁古海交换流（SME）两条次要通道。我们发现了三个准持续的中尺度涡旋：盆地北部（NSAE）的一个反气旋涡旋和西南（WSCE）和东南（ESCE）地区的两个气旋涡旋。WSCE的持续时间最长（60%），而ESCE的平均长度尺度最大（约118 km）。气旋涡旋在ITF减弱和SSI和SME增强期间增强，而反气旋变率与强ITF流入密切相关。综合分析和滞后分析表明，气旋涡旋使一部分ITF水再循环并转向马鲁古海，从而减少了通往望加锡海峡的有效通流。季节上，与涡旋活动相反，夏季北部ITF增强，初冬减弱，而年际上，La Niña （El Niño）期间ITF输送增强（减少），导致涡旋能量被抑制（增强）。研究结果强调了中尺度涡旋和ITF之间的双向相互作用，强调了当地涡旋动力学在调节印度-太平洋门户的ITF路径方面的关键作用。

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来源期刊

Progress in Oceanography 地学-海洋学

CiteScore

7.20

自引率

4.90%

发文量

138

审稿时长

3 months

期刊介绍： Progress in Oceanography publishes the longer, more comprehensive papers that most oceanographers feel are necessary, on occasion, to do justice to their work. Contributions are generally either a review of an aspect of oceanography or a treatise on an expanding oceanographic subject. The articles cover the entire spectrum of disciplines within the science of oceanography. Occasionally volumes are devoted to collections of papers and conference proceedings of exceptional interest. Essential reading for all oceanographers.