Ventilation changes in intermediate water on millennial time scales in the SE Nordic seas, 65‐14 kyr BP
Ventilation changes in intermediate water on millennial time scales in the SE Nordic seas, 65‐14 kyr BP
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北欧东南海中层水在千年时间尺度上的通风变化，65-14 kyr BP
DOI：
10.1029/2008gl036563
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发表时间：
2009
影响因子：
5.2
通讯作者：
E. Thomsen
中科院分区：
文献类型：
--
作者：
T. L. Rasmussen;E. Thomsen
北欧东南部773m水深的冰川底栖生物δ13C记录显示，∼65,000−14,000年前的通风发生了温和但明显的变化。末次最大冰期、温暖的冰期间期和较短的冰期以高的δ13C值为特征，表明北欧海域的中间水团通风良好。在寒冷的海因里希事件期间，δ13C值的下降意味着中间水通气量的减少。我们将这种减少归因于盐跃层的发展，导致对流停止，并从北欧海域流出。通风良好的流出水被更温暖的大西洋水取代，由于层结作用，大西洋水与大气隔绝。其最初较高的δ13C值因“老化”而降低。我们认为，由于与海因里希事件相比，这些事件的地理范围较小，因此在体育场期间，次表层大西洋水缺乏反应。
A glacial epibenthic δ13C record from 773 m water depth in the SE Nordic seas reveals moderate, but distinct changes in the ventilation ∼65,000−14,000 years ago. The Last Glacial Maximum, the warm interstadials, and the shorter stadials are characterized by high δ13C values indicating well‐ventilated intermediate water masses in the Nordic seas. Decreasing δ13C values during the cold Heinrich events signify a reduction in intermediate water ventilation. We attribute the reduction to the development of a halocline causing a stop in convection and outflow from the Nordic seas. The well‐ventilated outflow water is replaced by warmer Atlantic water, which due to the stratification is isolated from the atmosphere. Its initial high δ13C values are reduced due to 'ageing'. We ascribe the lack of response in the subsurface Atlantic Water during the stadials to the smaller geographical extent of these events as compared to the Heinrich events.