...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Paleoceanography >Exploring Globorotalia truncatulinoides coiling ratios as a proxy for subtropical gyre dynamics in the northwestern Atlantic Ocean during late Pleistocene Ice Ages
【24h】

Exploring Globorotalia truncatulinoides coiling ratios as a proxy for subtropical gyre dynamics in the northwestern Atlantic Ocean during late Pleistocene Ice Ages

机译：探索晚更新世冰期末西北大西洋副热带回旋动力学的球果总纲卷曲比

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We explore the use of the coiling direction of planktic foraminifer Globorotalia truncatulinoides in sediment cores from the northwestern subtropical Atlantic Ocean as a proxy for variations in the intensity of the western boundary of the subtropical gyre over the past 280kyr. Core-top sediments from the study region are dominated by the left coiling variety consistent with the deep permanent thermocline at the study sites (KNR140-37PC and Ocean Drilling Program Site 1059). Downcore G. truncatulinoides (sinistral) maxima occur in conjunction with 14 out of the 25 (Northern and Southern Hemisphere) precession maxima contained in the study interval. The agreement between the dominance of left coiling tests and the precession index of the Southern Hemisphere, in particular, supports a link between a deep thermocline in the northwestern subtropical Atlantic and northward flow of equatorially sourced warm surface currents, a situation analogous to the Late Holocene. Interglacial marine oxygen isotope stage (MIS) 5 lacks G. truncatulinoides (s) minima attesting to the relative stability of the western boundary during an interval of prolonged global warmth. G. truncatulinoides (s) disappear during the glacial extremes of MIS 2, 6, and 8 implying a weaker western boundary current at these times. Our results support that the coiling direction of this species is sensitive to variations in hydrography of the western boundary of the subtropical gyre. Because of the association between G. truncatulinoides (s) and precession maxima in both hemispheres, results support the importance of oceanic heat transport in half-precession climate variability in the North Atlantic.
机译：我们探索了西北亚热带大西洋沉积岩芯中板状有孔虫Globorotalia truncatulinoides的卷曲方向的使用，以作为过去280kyr副热带涡旋西边界强度变化的代表。来自研究区域的岩心顶部沉积物主要由左盘旋形式主导，这与研究地点（KNR140-37PC和Ocean Drilling Program Site 1059）上的深部永久性高温跃层一致。在研究区间包含的25个（北半球和南半球）岁差最大值中，有14个发生了下限G. truncatulinoides（正弦）最大值。左旋试验的优势与南半球的进动指数之间的一致性，尤其支持西北亚热带大西洋的深层热跃层与赤道源热表面流向北流动之间的联系，这种情况类似于晚全新世。 。冰川间海洋氧同位素阶段（MIS）5缺乏最小化的G. truncatulinoides（s），证明了在长期全球变暖的间隔内，西部边界的相对稳定性。在MIS 2、6和8的冰河极端期间，G。truncatulinoides消失了，这意味着此时的西部边界流减弱。我们的结果支持该物种的盘旋方向对亚热带回旋区西边界水文学的变化敏感。由于两个半球中的截齿丁香球菌和最大进动之间存在关联，因此，结果支持了海洋热量运输对北大西洋半进动气候变异的重要性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号