Effect of an Open Central American Seaway on Ocean Circulation and the Oxygen Minimum Zone in the Tropical Pacific From Model Simulations
Effect of an Open Central American Seaway on Ocean Circulation and the Oxygen Minimum Zone in the Tropical Pacific From Model Simulations
复制标题
DOI：
10.1029/2023gl103728
复制
发表时间：
2023-10
影响因子：
5.2
通讯作者：
V. Khon;B. Hoogakker;B. Schneider;J. Segschneider;W. Park
中科院分区：
文献类型：
--
作者：
V. Khon;B. Hoogakker;B. Schneider;J. Segschneider;W. Park
中新世中期至上新世中期（∼16-3 Ma BP）期间中美洲海道（CAS）的构造闭合被认为是当今热带太平洋氧气最低区（OMZ）开始的关键时期。在这项研究中，我们研究了开放的 CAS 对热带太平洋海洋环流和 OMZ 的影响。我们使用基尔气候模型进行了一系列敏感性实验，其中我们将 CAS 窗台深度从浅到深变化。我们发现，在开放 CAS 期间，东部热带太平洋 OMZ 发育程度较低。这主要是由于向东的地下洋流增强，促进了西热带太平洋的氧气供应增加。此外，海洋初级生产力净值小幅下降以及随后颗粒有机碳出口减弱导致赤道东太平洋地下氧消耗量减少。
The tectonic closure of the Central American Seaway (CAS) during the mid‐Miocene to mid‐Pliocene (∼16–3 Ma BP) is thought of as a key interval for the onset of the present‐day tropical Pacific oxygen minimum zone (OMZ). In this study we investigate the impact of an open CAS on the ocean circulation and the OMZ in the tropical Pacific. We perform a series of sensitivity experiments with the Kiel Climate Model, where we vary the CAS sill depth from shallow to deep. We find that the eastern tropical Pacific OMZ was less developed during the period of an open CAS. This is driven mainly by an enhanced eastward subsurface current that facilitated an increased oxygen supply from the western tropical Pacific. In addition, a small decrease in net marine primary production and subsequent weaker export of particulate organic carbon induced less subsurface oxygen consumption in the Eastern Equatorial Pacific.