Oceanographic dynamics and the end of the last interglacial in the subpolar North Atlantic

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Mokeddem, Zohra, McManus, Jerry F., Oppo, Delia W.
• Format: Text
• Language: English
• Published: National Academy of Sciences 2014
• Subjects: Physical Sciences; Arctic; Climate change; North Atlantic
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4128163; http://www.ncbi.nlm.nih.gov/pubmed/25049405; https://doi.org/10.1073/pnas.1322103111

The last interglacial, ∼125,000 y ago, was the last extended warm period the earth has known before our Common Era of the past 11,000 y. Its end came after ∼15,000 y, paced by the decline in northern summer insolation, and followed by a glacial age lasting 100,000 y. Yet the ocean dynamics contributing to this glacial initiation and its global propagation are not fully understood, nor are their general role in climate evolution understood. This study assesses the role of the ocean’s gyre systems and fronts as dynamical components in large-scale climate change. Using microfossils, we document progressive southward advances of Arctic and polar hydrographic fronts into the subpolar North Atlantic Ocean, which trigger regional coolings and accelerate the transition into the glacial age.