DOI: 10.1016/j.epsl.2018.07.035
Scopus记录号: 2-s2.0-85051110638
论文题名: The amplifying effect of Indonesian Throughflow heat transport on Late Pliocene Southern Hemisphere climate cooling
作者: De Vleeschouwer D. ; Auer G. ; Smith R. ; Bogus K. ; Christensen B. ; Groeneveld J. ; Petrick B. ; Henderiks J. ; Castañeda I.S. ; O'Brien E. ; Ellinghausen M. ; Gallagher S.J. ; Fulthorpe C.S. ; Pälike H.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 500 起始页码: 15
结束页码: 27
语种: 英语
英文关键词: astronomical forcing
; Indonesian Throughflow
; Leeuwin Current
; M2 event
; Pliocene
; West Pacific Warm Pool
Scopus关键词: Glacial geology
; Lakes
; Sea level
; Astronomical forcing
; Indonesian throughflow
; Leeuwin current
; M2 event
; Pliocene
; West pacific
; Heat transfer
; cooling
; glaciation
; global climate
; heat flow
; heat transfer
; Pliocene
; sea surface temperature
; Southern Hemisphere
; thermohaline structure
; throughflow
; warm pool
; Indian Ocean
; Pacific Ocean
; Foraminifera
; Globigerinoides sacculifer
英文摘要: An unusually short glaciation interrupted the warm Pliocene around 3.3 Ma (Marine Isotope Stage (MIS) M2). Different hypotheses exist to explain why this glaciation event was so pronounced, and why the global climate system returned to warm Pliocene conditions relatively quickly afterwards. One of these proposed mechanisms is a reduced equator-to-pole heat transfer, in response to a tectonically reduced Indonesian Throughflow (ITF). The ITF is a critical part of the global thermohaline ocean circulation, transporting heat from the Indo-Pacific Warm Pool to the Indian Ocean. When ITF connectivity is reduced, the water and heat supply for the Leeuwin Current, flowing poleward along Australia's west coast, is also diminished. To assess the possible relationship between mid-Pliocene glaciations and latitudinal heat transport through the Indonesian Throughflow, we constructed a multi-proxy orbital-scale record for the 3.7–2.8 Ma interval from International Ocean Discovery Program (IODP) Site U1463, off northwest Australia. The comparison of the Site U1463 record with paleoclimate records from nearby Site 763 and West Pacific Warm Pool Site 806 allows for a detailed regional reconstruction of Pliocene paleoceanography and thus for testing the proposed hypothesis. An astronomically-paced decrease in potassium content characterizes the late Pliocene interval of U1463. This record documents the increasing aridity of northwest Australia, periodically alleviated by reinforced summer monsoon precipitation under summer insolation maxima. The δ18O record of the planktonic foraminifer Globigerinoides sacculifer correlates exceptionally well with the sea surface temperature (SST) record from Site 806 in the West Pacific Warm Pool, even during MIS M2. Hence, Site U1463 preserves an uninterrupted ITF signal even during Pliocene glaciations. However, the U1463 δ18OG.sacculifer record exhibits a 0.5‰ offset with the nearby Site 763A record around MIS M2. This implies that Site 763A, about 500 km west of U1463, more closely tracks Indian Ocean SST records across MIS M2. The U1463 data reveal that heat-transport through the Indonesian Throughflow did not shut down completely during MIS M2, but rather its intensity decreased prior to and during MIS M2, causing Site 763A to temporarily reflect an Indian Ocean, rather than an ITF signal. We conclude that ITF variability significantly influenced latitudinal heat transport by means of the Leeuwin Current and hence contributed to the relative intensity of MIS M2. We propose the ITF valve between the Pacific and Indian Ocean as a positive feedback mechanism, in which an initial sea level lowering reduces ITF heat transport, in turn amplifying global cooling by advancing the thermal isolation of Antarctica. © 2018 Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109700
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
There are no files associated with this item.
作者单位: MARUM-Center for Marine and Environmental Sciences, University of Bremen, Klagenfurterstraße 2-4, Bremen, 28359, Germany; Department of Biogeochemistry, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Kanagawa, 237-0061, Japan; Department of Geosciences, University of Massachusetts at Amherst, Amherst, MA 01003, United States; International Ocean Discovery Program, Texas A&M University, College Station, 77845-9547, United States; Environmental Studies Program, Adelphi University, Garden City, NY 11530, United States; Max-Planck-Institut für Chemie, Mainz, 55128, Germany; Department of Earth Sciences, Uppsala University, Uppsala, 75236, Sweden; Department of Geology and Geophysics, Texas A&M University, College Station, TX 77843, United States; School of Earth Sciences, University of Melbourne, Melbourne, 3010, Australia; Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, 78758-4445, United States
Recommended Citation:
De Vleeschouwer D.,Auer G.,Smith R.,et al. The amplifying effect of Indonesian Throughflow heat transport on Late Pliocene Southern Hemisphere climate cooling[J]. Earth and Planetary Science Letters,2018-01-01,500