Coupled Impacts of Atmospheric Circulation and Sea-Ice on Late Pleistocene Terrigenous Sediment Dynamics in the Subarctic Pacific Ocean

• Published in: Geophysical Research Letters
• Main Authors: Zhong, Yi, Liu, Yanguang, Gong, Xun, Wilson, David J., Lu, Zhengyao, Liu, Jiabo, Song, Tengfei, Gorbarenko, Sergey A., Shi, Xuefa, Yang, Xiaoqiang, Liu, Qingsong
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union (AGU) 2021
• Subjects: Geology; Climate Research; Bering Sea; Pacific; aleutian low; Sea ice; Subarctic
• Online Access: https://lup.lub.lu.se/record/10173fd4-e987-4934-9c4c-80107fc5fe95; https://doi.org/10.1029/2021GL095312

Processes controlling environmental change in the subarctic Pacific Ocean on millennial to orbital timescales are not well understood. Here we use a 230-kyr sedimentary record from the northwest Pacific Ocean to assess the response of late Pleistocene sediment dynamics to orbital forcing. Combining a source-to-sink perspective based on sedimentological records with climate model reanalysis, we reveal that fluctuations in sediment provenance were closely linked to obliquity-forced changes in atmospheric circulation modes. Specifically, the position of the Aleutian Low controlled sediment transport from the Bering Sea and Aleutian Arc sources. Furthermore, a distinct shift in North Pacific ocean circulation during the Last Glacial Maximum may have been related to a strengthened Siberian High. The coincidence of atmospheric mode switches with changes in sea-ice extent and North Pacific Intermediate Water formation in the marginal seas suggests that this coupled ocean-atmosphere system may have acted as a regional amplifier of global climate variability.