State Key Laboratory of Marine Environmental Science, and Department of Physical Oceanography, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.
Agency for Marine and Fisheries Research and Development, Ministry of Marine Affairs and Fisheries, Jakarta, Indonesia.
Sci Rep. 2019 May 14;9(1):7364. doi: 10.1038/s41598-019-43841-z.
The Earth has experienced a global surface warming slowdown (GSWS) or so-called "global warming hiatus" since the end of the 20 century. The GSWS was marked by a La Niña-like decadal cooling in the Pacific Ocean that subsequently generated an increase in the transfer of Pacific waters into the Indian Ocean via the Indonesian Throughflow (ITF). How the Pacific water spreads through the interior of the Indian Ocean and the impact of these decadal ITF transport changes on the Indian Ocean water mass transformation and circulation remain largely unknown. Here, we analyze the thermohaline structures and current systems at different depths in the Indian Ocean prior to and during the GSWS period. Our study shows that the GSWS involved extensive changes to the Indo-Pacific ocean teleconnection system, characterized by subsurface warming and freshening in the Indian Ocean. A hitherto unknown Indian Ocean pathway of the ITF was discovered off Sumatra associated with prolonged northwestward flow within the South Java Current. Our analysis uncovers a direct linkage of enhanced ITF waters with the Agulhas Current in the Mozambique Channel from thermocline depths down to intermediate depths, that freshened the Indian Ocean. These changes in the Indian Ocean circulation and water mass characteristics impact climate variability through changing the sea surface temperature (SST) and precipitation patterns that can subsequently affect regional economies.
自 20 世纪末以来，地球经历了全球地表变暖减缓（GSWS）或所谓的“全球变暖停顿”。GSWS 的特点是太平洋出现类似拉尼娜的十年期冷却，随后通过印度尼西亚贯穿流（ITF）增加了太平洋水向印度洋的转移。太平洋水如何在印度洋内部传播，以及这些年代际 ITF 输送变化对印度洋水团转化和环流的影响在很大程度上仍然未知。在这里，我们分析了 GSWS 前后印度洋不同深度的热盐结构和海流系统。我们的研究表明，GSWS 涉及到印度洋-太平洋海洋遥相关系统的广泛变化，其特征是印度洋次表层变暖变咸。在苏门答腊附近发现了一个迄今为止未知的 ITF 印度洋途径，与南爪哇流内的西北向流延长有关。我们的分析揭示了增强的 ITF 水与莫桑比克海峡的亚速尔群岛流之间的直接联系，从温跃层深度到中层深度，使印度洋变咸。这些印度洋环流和水团特征的变化通过改变海面温度（SST）和降水模式来影响气候变率，从而随后影响区域经济。
