The last five glacial-interglacial transitions: A high-resolution 450,000-year record from the subantarctic Atlantic
The last five glacial-interglacial transitions: A high-resolution 450,000-year record from the subantarctic Atlantic
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DOI：
10.1029/2007pa001457
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发表时间：
2007-10-19
期刊：
影响因子：
--
通讯作者：
Gersonde, R.
中科院分区：
文献类型：
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作者：
Cortese, G.;Abelmann, A.;Gersonde, R.
基于放射虫的亚千年分辨率夏季海面温度记录记录了南大西洋副热带锋区最近5次冰期到间冰期的转变。在冰期和间冰期都有快速的波动，而在冰期结束时的突然降温事件是反复发生的。来自同一地核的地表水文和全球冰量代用数据表明，夏季海温在终止前的增加导致全球冰量减少4.7 +/- 3.7 ka（偏心带）、6.9 +/- 2.5 ka（倾角）和2.7 +/- 0.9 ka（岁差）。海温与底栖三角洲C-13的比较表明，亚南极北部表层、中层和深水团对北大西洋冷事件的响应存在解耦。我们的海温记录与MD97-2120（西南太平洋）地核海温记录的匹配特征表明，气候事件的超区域表达在很大程度上受单一气候因子的影响：副热带锋、气候变化转移的放大器和载体。Vostok的δ t站点变暖与ODP站点1089的海温变暖之间的直接相关性表明，变暖的海洋/大气条件意味着锋面系统更向南放置，梯度更弱，因此阿古拉斯向大西洋的输入更强。
A submillennial resolution, radiolarian-based record of summer sea surface temperature (SST) documents the last five glacial to interglacial transitions at the subtropical front, southern Atlantic Ocean. Rapid fluctuations occur both during glacial and interglacial intervals, and sudden cooling episodes at glacial terminations are recurrent. Surface hydrography and global ice volume proxies from the same core suggest that summer SST increases prior to terminations lead global ice- volume decreases by 4.7 +/- 3.7 ka (in the eccentricity band), 6.9 +/- 2.5 ka (obliquity), and 2.7 +/- 0.9 ka (precession). A comparison between SST and benthic delta C-13 suggests a decoupling in the response of northern subantarctic surface, intermediate, and deep water masses to cold events in the North Atlantic. The matching features between our SST record and the one from core MD97-2120 (southwest Pacific) suggests that the super-regional expression of climatic events is substantially affected by a single climatic agent: the Subtropical Front, amplifier and vehicle for the transfer of climatic change. The direct correlation between warmer Delta T-site at Vostok and warmer SST at ODP Site 1089 suggests that warmer oceanic/atmospheric conditions imply a more southward placed frontal system, weaker gradients, and therefore stronger Agulhas input to the Atlantic Ocean.