Mindanao Dome variability over the last 160 kyr: Episodic glacial cooling of the West Pacific Warm Pool
Mindanao Dome variability over the last 160 kyr: Episodic glacial cooling of the West Pacific Warm Pool
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DOI：
10.1029/2010pa001966
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发表时间：
2011-02-26
期刊：
影响因子：
--
通讯作者：
Garbe-Schoenberg, Dieter
中科院分区：
文献类型：
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作者：
Bolliet, Timothe;Holbourn, Ann;Garbe-Schoenberg, Dieter
我们目前的海平面，上层温跃层，和底栖三角洲O-18数据，以及温度和古生产力代理数据，从国际海洋全球变化研究计划（IECHO）核心MD 06 -3067（6度31' N，126度30' E，1575米水深），位于西赤道太平洋棉兰老海流的流动路径内。我们的记录揭示了相当大的冰川间冰期和亚轨道的变化在棉兰老岛圆顶上升流在过去的160 kyr。冰穹活动普遍加强在冰期导致较冷的温跃层沃茨，而它大幅下降，特别是在全新世早期和早期海洋氧同位素阶段（MIS）5e，当上升流沃茨没有达到温跃层。在MIS 3和MIS 2，增强的表面生产力，以及显着的低SST和低上层海洋热对比度提供证据，情节冰川上升流到表面，而短暂的表面变暖标志着定期崩溃的棉兰老岛穹上升在海因里希事件。我们将MIS 3和MIS 2期间的高变率归因于影响北方冬季季风风和上层海洋环流的厄尔尼诺-南方涛动状态的变化。冰川上升流加强时，一个强大的气旋环流成为建立，而厄尔尼诺现象的条件下，在海因里希事件往往会抑制气旋环流，减少埃克曼运输。因此，我们的研究结果表明，棉兰老岛穹上升流的变化与热带对流的位置和强度密切相关，也反映了高纬度地区的远场影响。
We present sea surface, upper thermocline, and benthic delta O-18 data, as well as temperature and paleoproductivity proxy data, from the International Marine Global Change Study Program (IMAGES) Core MD06-3067 (6 degrees 31' N, 126 degrees 30' E, 1575 m water depth), located in the western equatorial Pacific Ocean within the flow path of the Mindanao Current. Our records reveal considerable glacial-interglacial and suborbital variability in the Mindanao Dome upwelling over the last 160 kyr. Dome activity generally intensified during glacial intervals resulting in cooler thermocline waters, whereas it substantially declined during interglacials, in particular in the early Holocene and early marine oxygen isotope stage (MIS) 5e, when upwelling waters did not reach the thermocline. During MIS 3 and MIS 2, enhanced surface productivity together with remarkably low SST and low upper ocean thermal contrast provide evidence for episodic glacial upwelling to the surface, whereas transient surface warming marks periodic collapses of the Mindanao Dome upwelling during Heinrich events. We attribute the high variability during MIS 3 and MIS 2 to changes in the El Nino-Southern Oscillation state that affected boreal winter monsoonal winds and upper ocean circulation. Glacial upwelling intensified when a strong cyclonic gyre became established, whereas El Nino-like conditions during Heinrich events tended to suppress the cyclonic circulation, reducing Ekman transport. Thus, our findings demonstrate that variations in the Mindanao Dome upwelling are closely linked to the position and intensity of the tropical convection and also reflect far-field influences from the high latitudes.