Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination.
Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination.
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DOI：
10.1038/srep39979
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发表时间：
2017-01-05
影响因子：
4.6
通讯作者：
Cooper A
中科院分区：
文献类型：
--
作者：
Fogwill CJ;Turney CS;Golledge NR;Etheridge DM;Rubino M;Thornton DP;Baker A;Woodward J;Winter K;van Ommen TD;Moy AD;Curran MA;Davies SM;Weber ME;Bird MI;Munksgaard NC;Menviel L;Rootes CM;Ellis B;Millman H;Vohra J;Rivera A;Cooper A
重建南极冰盖对末次冰期（LGT; 18，000 - 11，650年前）变暖的动态响应使我们能够解开冰气候反馈，这是改善未来预测的关键。虽然这一时期的事件顺序是相当众所周知的，但相对较差的年代控制排除了冰，大气和海洋记录的精确对齐，使得难以评估南极冰盖（AIS）动态，气候变化和海平面之间的关系。在这里，我们提出了一个高分辨率的“水平冰芯”从威德尔海湾，记录千年尺度的AIS动态在这个广泛的地区的结果。与直觉相反，我们发现AIS在整个南极寒冷时期（ACR; 14，600 - 12，700年前）的质量损失，在随后的数千年大气变暖期间稳定下来。地球系统和冰盖模型表明，这些对比鲜明的趋势可能是全舌状的，由环极深水输送到大陆架放大的反馈维持。考虑到LGT的半球间气候趋势之间的反相位关系，我们的研究结果表明，南大洋AIS反馈是由全球大气遥相关控制的。随着南大洋层结的增加和今天中纬度西风的加强，这种遥相关可能会放大AIS的质量损失并加速全球海平面上升。
Reconstructing the dynamic response of the Antarctic ice sheets to warming during the Last Glacial Termination (LGT; 18,000–11,650 yrs ago) allows us to disentangle ice-climate feedbacks that are key to improving future projections. Whilst the sequence of events during this period is reasonably well-known, relatively poor chronological control has precluded precise alignment of ice, atmospheric and marine records, making it difficult to assess relationships between Antarctic ice-sheet (AIS) dynamics, climate change and sea level. Here we present results from a highly-resolved ‘horizontal ice core’ from the Weddell Sea Embayment, which records millennial-scale AIS dynamics across this extensive region. Counterintuitively, we find AIS mass-loss across the full duration of the Antarctic Cold Reversal (ACR; 14,600–12,700 yrs ago), with stabilisation during the subsequent millennia of atmospheric warming. Earth-system and ice-sheet modelling suggests these contrasting trends were likely Antarctic-wide, sustained by feedbacks amplified by the delivery of Circumpolar Deep Water onto the continental shelf. Given the anti-phase relationship between inter-hemispheric climate trends across the LGT our findings demonstrate that Southern Ocean-AIS feedbacks were controlled by global atmospheric teleconnections. With increasing stratification of the Southern Ocean and intensification of mid-latitude westerly winds today, such teleconnections could amplify AIS mass loss and accelerate global sea-level rise.
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影响因子：
4.6
作者：
Fogwill CJ;Turney CS;Golledge NR;Etheridge DM;Rubino M;Thornton DP;Baker A;Woodward J;Winter K;van Ommen TD;Moy AD;Curran MA;Davies SM;Weber ME;Bird MI;Munksgaard NC;Menviel L;Rootes CM;Ellis B;Millman H;Vohra J;Rivera A;Cooper A
通讯作者：
Cooper A
影响因子：
64.8
作者：
Luethi, Dieter;Le Floch, Martine;Stocker, Thomas F.
通讯作者：
Stocker, Thomas F.
影响因子：
64.8
作者：
Blunier, T;Chappellaz, J;Johnsen, SJ
通讯作者：
Johnsen, SJ
影响因子：
18.3
作者：
Jacobs, Stanley S.;Jenkins, Adrian;Dutrieux, Pierre
通讯作者：
Dutrieux, Pierre
影响因子：
4
作者：
Menviel, L.;Timmermann, A.;Mouchet, A.
通讯作者：
Mouchet, A.