Increased reservoir ages and poorly ventilated deep waters inferred in the glacial Eastern Equatorial Pacific.
Increased reservoir ages and poorly ventilated deep waters inferred in the glacial Eastern Equatorial Pacific.
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DOI：
10.1038/ncomms8420
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发表时间：
2015-07-03
影响因子：
16.6
通讯作者：
Cacho I
中科院分区：
文献类型：
--
作者：
de la Fuente M;Skinner L;Calvo E;Pelejero C;Cacho I
长期以来，人们一直在寻找一致的证据，证明在最后一次冰消期，通风不良的太平洋深海可能将其放射性碳贫化的碳储存释放到大气中。这种证据仍然缺乏，部分原因是缺乏准确估计深海通风年龄所需的表层储层年龄重建。在这里，我们结合联合收割机新的放射性碳数据从东赤道太平洋（EEP）与年代地层日历年龄的限制，以估计浅层地下水库年龄的变化，从而提供深海通风年龄的估计。浅水和深水通气年龄下降，在最后一次冰消期，与类似的重建南太平洋和南大洋。所观察到的区域指纹连接南大洋和EEP是一致的一个占主导地位的南源EEP温跃层沃茨，并建议相对不变的海洋内部运输途径，但显着减少的空气-海洋气体交换在冰川南部高纬度地区。 精确的深太平洋通风年龄阻碍了穷人的表面水库年龄重建。在这里，作者产生了新的通风年龄为东赤道太平洋的深层沃茨，这表明减少海气交换在末次冰期。
Consistent evidence for a poorly ventilated deep Pacific Ocean that could have released its radiocarbon-depleted carbon stock to the atmosphere during the last deglaciation has long been sought. Such evidence remains lacking, in part due to a paucity of surface reservoir age reconstructions required for accurate deep-ocean ventilation age estimates. Here we combine new radiocarbon data from the Eastern Equatorial Pacific (EEP) with chronostratigraphic calendar age constraints to estimate shallow sub-surface reservoir age variability, and thus provide estimates of deep-ocean ventilation ages. Both shallow- and deep-water ventilation ages drop across the last deglaciation, consistent with similar reconstructions from the South Pacific and Southern Ocean. The observed regional fingerprint linking the Southern Ocean and the EEP is consistent with a dominant southern source for EEP thermocline waters and suggests relatively invariant ocean interior transport pathways but significantly reduced air–sea gas exchange in the glacial southern high latitudes. Accurate deep Pacific Ocean ventilation ages are hindered by poor surface reservoir age reconstructions. Here, the authors generate new ventilation ages for the deep waters of the Eastern Equatorial Pacific, which indicate reduced air-sea gas exchange during the last glacial.