Coupling of the Intertropical Convergence Zone and Southern Hemisphere mid-latitude climate during the early to mid-Holocene

Mariani, Michela; Fletcher, Michael-Shawn; Drysdale, Russell N.; Saunders, Krystyna M.; Heijnis, Henk; Jacobsen, Geraldine; Zawadzki, Atun

Abstract

Conceptual models predict a tight coupling between the Intertropical Convergence Zone (ITCZ) and the Southern Westerly Winds (SWW) in response to glacial-interglacial transitions, yet little is known about this relationship under Holocene boundary conditions. Here we present a synthesis of Holocene pollen data from the southwest Pacific mid-latitudes that tracks changes in the SWW. Comparison of our SWW paleoclimate records with data tracking the ITCZ, oceanic circulation, and insolation reveals clearly synchronous and in-phase ITCZ-SWW dynamics between 12 and 5 ka, indicating a tight coupling between the tropics and southern mid-latitudes in response to ocean circulation and insolation. An apparent decoupling of the SWW and ITCZ in the Pacific region after 5 ka is attributable to the overriding influence of the El Niño–Southern Oscillation (ENSO) over the proxy data.

Citation

Mariani, M., Fletcher, M.-S., Drysdale, R. N., Saunders, K. M., Heijnis, H., Jacobsen, G., & Zawadzki, A. (2017). Coupling of the Intertropical Convergence Zone and Southern Hemisphere mid-latitude climate during the early to mid-Holocene. Geology, 45(12), 1083-1086. https://doi.org/10.1130/G39705.1

• Journal Article Type: Article
• Acceptance Date: Sep 14, 2017
• Online Publication Date: Oct 27, 2017
• Publication Date: Dec 20, 2017
• Deposit Date: Feb 20, 2019
• Publicly Available Date: Feb 21, 2019
• Journal: Geology
• Print ISSN: 0091-7613
• Electronic ISSN: 1943-2682
• Publisher: Geological Society of America
• Peer Reviewed: Peer Reviewed
• Volume: 45
• Issue: 12
• Pages: 1083-1086
• DOI: https://doi.org/10.1130/G39705.1
• Public URL: https://nottingham-repository.worktribe.com/output/1573965
• Publisher URL: https://pubs.geoscienceworld.org/gsa/geology/article/45/12/1083/519762/coupling-of-the-intertropical-convergence-zone-and
• Contract Date: Feb 20, 2019