Cover Image

Wind and buoyancy controls on productivity and bottom current in the Pacific Antarctic seasonal sea-ice zone since 300 ka

Whether upwelling-driven surface productivity and bottom current strength respond coherently to climatic forcing remains unclear, limiting geological constraints on Southern Ocean surface-deep linkage across glacial-interglacial cycles. Here, we reconstructed ∼300 kyr of productivity and bottom curr...

Full description

Saved in:
Bibliographic Details
Main Authors: Wang, Jiakai (Author) , Guo, Jingteng (Author) , Xiao, Wenshen (Author) , Tang, Zheng (Author) , Qin, Bingbin (Author) , Lippold, Jörg (Author) , Xiong, Zhifang (Author) , Li, Tiegang (Author)
Format: Article (Journal)
Language:English
Published: July 2026
In: Global and planetary change
Year: 2026, Volume: 262, Pages: 1-17
ISSN:1872-6364
DOI:10.1016/j.gloplacha.2026.105468
Online Access:Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1016/j.gloplacha.2026.105468
Verlag, lizenzpflichtig, Volltext: https://www.sciencedirect.com/science/article/pii/S092181812600189X
Get full text
Author Notes:Jiakai Wang, Jingteng Guo, Wenshen Xiao, Zheng Tang, Bingbin Qin, Jörg Lippold, Zhifang Xiong, Tiegang Li
Description
Summary:Whether upwelling-driven surface productivity and bottom current strength respond coherently to climatic forcing remains unclear, limiting geological constraints on Southern Ocean surface-deep linkage across glacial-interglacial cycles. Here, we reconstructed ∼300 kyr of productivity and bottom current strength in the Pacific Antarctic seasonal sea-ice zone (SIZ), based on multi-proxy data from core ANT36/A3-08, using a chronology constrained by core-top radiocarbon, tephrostratigraphy, and orbital-scale geochemical correlation. Through glacial-interglacial cycles, productivity and bottom current strength covary, with higher values during interglacials and lower during glacials. This pattern is consistent with large-scale vertically coupled responses to meridional shifts of Southern Hemisphere Westerly Winds (SWW), which modulate surface upwelling and bottom currents along the Pacific Antarctic margin. Superimposed on this orbital-scale pattern are transient anomalies driven by buoyancy and atmospheric forcing. At the MIS 6/5 transition, meltwater-induced stratification counteracted the expected SWW-driven intensification, producing muted increases in productivity and bottom current strength, despite a pronounced poleward shift of SWW. During MIS 2, both records intensified briefly, coinciding with heightened variability in the Amundsen Sea Low (ASL). Stronger ASL variability likely enhanced sea-ice divergence and intermittent polynya formation, thereby strengthening brine rejection. Together, these paired productivity and bottom current signals are interpreted to reflect changes in upper-limb upwelling and lower-limb deep renewal at the Pacific Antarctic margin, providing a site-scale imprint of broader Southern Ocean overturning adjustments and highlighting sensitivity to future SWW shifts and increasing Antarctic meltwater input.
Item Description:Online verfügbar: 3. April 2026, Artikelversion: 10. April 2026
Gesehen am 11.06.2026
Physical Description:Online Resource
ISSN:1872-6364
DOI:10.1016/j.gloplacha.2026.105468

Similar Items