Orbital Controls on North Pacific Dust Flux During the Late Quaternary

• Published in: Geophysical Research Letters
• Main Authors: Zhong, Yi, Liu, Yanguang, Yang, Hu, Yin, Qiuzhen, Wilson, David J., Lu, Zhengyao, Jaccard, Samuel L., Struve, Torben, Clift, Peter D., Kaboth-Bahr, Stefanie, Larrasoaña, Juan C., Bahr, André, Gong, Xun, Zhao, Debo, Zhang, Yanan, Xia, Wenyue, Liu, Qingsong
• Other Authors: National Natural Science Foundation of China, Tongji University, Shanghai Sheshan National Geophysical Observatory (China), Shenzhen Science and Technology Innovation Commission, Natural Environment Research Council (UK), Louisiana State University
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2024
• Subjects: Pacific; Subarctic
• Online Access: http://hdl.handle.net/10261/366328; https://doi.org/10.1029/2023GL106631; https://api.elsevier.com/content/abstract/scopus_id/85185269172

[EN] Airborne mineral dust is sensitive to climatic changes, but its response to orbital forcing is still not fully understood. Here, we present a reconstruction of dust input to the Subarctic Pacific Ocean covering the past 190 kyr. The dust composition record is indicative of source moisture conditions, which were dominated by precessional variations. In contrast, the dust flux record is dominated by obliquity variations and displays an out-of-phase relationship with a dust record from the mid-latitude North Pacific Ocean. Climate model simulations suggest precession likely drove changes in the aridity and extent of dust source regions. Additionally, the obliquity variations in dust flux can be explained by meridional shifts in the North Pacific westerly jet, driven by changes in the meridional atmospheric temperature gradient. Overall, our findings suggest that North Pacific dust input was primarily modulated by orbital-controlled source aridity and the strength and position of the westerly winds. This work was supported financially by the National Natural Science Foundation of China (Grant 42274094, 92158208, 42176245, 42261144739, 41976065, 42176066), the State Key Laboratory of Marine Geology, Tongji University (No. MGK202209), the opening foundation (SSKP202101) of the Shanghai Sheshan National Geophysical Observatory (Shanghai, China), the State Key Laboratory of Marine Geology, and Shenzhen Science and Technology Program (KQTD20170810111725321). DJW was supported by a NERC independent research fellowship (NE/T011440/1). PDC was supported by the Charles T. McCord Jr Chair in Petroleum Geology at LSU. Peer reviewed