1
|
Le Houedec S, Tremblin M, Champion A, Samankassou E. Modulation of the northward penetration of Antarctica intermediate waters into the eastern equatorial Indian Ocean under glacial and interglacial conditions. Sci Rep 2024; 14:6673. [PMID: 38509205 PMCID: PMC11349886 DOI: 10.1038/s41598-024-57411-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 03/18/2024] [Indexed: 03/22/2024] Open
Abstract
The Indo-Pacific warm pool is the warmest and most dynamic ocean-atmosphere-climate system on Earth and was subject to significant climate changes during the Pleistocene glacial-interglacial transitions. This has been shown to significantly affected the strength of surface waters that redistribute heat from the tropics to the southern part of the Indian Ocean. Here we investigate the response of the oceanic circulation at intermediate depth (1200 m) of the eastern equatorial Indian Ocean (EEIO) with neodymium (Nd) isotopes in the context of the climatic oscillation of the last 500 ka. The most striking feature of our new dataset is the seesaw Nd record that mimics glacial-interglacial cycles. While the interglacial periods are characterized by a higher contribution of the less radiogenic neodymium (~ - 7εNd) Antarctic Intermediate Water (AAIW), the glacial periods are characterized by more radiogenic water mass of Pacific origin (~ - 5εNd). To explain the increase in the εNd signature toward a more radiogenic signature as the Indo-Pacific connection is reduced under the low sea level of the glacial periods, we show that under global cooling, the AAIW advances northward into the tropics, which is a consequence of the general slowdown of the thermohaline circulation. Therefore, oceanic mixing at intermediate depth in the eastern tropical Indian intermediate water is modulated by the production rate of the AAIW in the Southern Ocean. Our study provides new evidence for the role that changes in the deep oceanic conditions play in amplifying externally forced climate changes that ultimately lead to drier/moister atmospheric conditions and weaker/stronger monsoons during glacial/interglacial periods over eastern tropical Indian Ocean.
Collapse
Affiliation(s)
- Sandrine Le Houedec
- Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205, Geneva, Switzerland.
| | - Maxime Tremblin
- Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205, Geneva, Switzerland
| | - Amaury Champion
- Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205, Geneva, Switzerland
| | - Elias Samankassou
- Department of Earth Sciences, University of Geneva, Rue des Maraîchers 13, 1205, Geneva, Switzerland
| |
Collapse
|
2
|
Gong L, Holbourn A, Kuhnt W, Opdyke B, Zhang Y, Ravelo AC, Zhang P, Xu J, Matsuzaki K, Aiello I, Beil S, Andersen N. Middle Pleistocene re-organization of Australian Monsoon. Nat Commun 2023; 14:2002. [PMID: 37037802 PMCID: PMC10086051 DOI: 10.1038/s41467-023-37639-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 03/24/2023] [Indexed: 04/12/2023] Open
Abstract
The sensitivity of the Australian Monsoon to changing climate boundary conditions remains controversial due to limited understanding of forcing processes and past variability. Here, we reconstruct austral summer monsoonal discharge and wind-driven winter productivity across the Middle Pleistocene Transition (MPT) in a sediment sequence drilled off NW Australia. We show that monsoonal precipitation and runoff primarily responded to precessional insolation forcing until ~0.95 Ma, but exhibited heightened sensitivity to ice volume and pCO2 related feedbacks following intensification of glacial-interglacial cycles. Our records further suggest that summer monsoon variability at the precessional band was closely tied to the thermal evolution of the Indo-Pacific Warm Pool and strength of the Walker circulation over the past ~1.6 Myr. By contrast, productivity proxy records consistently tracked glacial-interglacial variability, reflecting changing rhythms in polar ice fluctuations and Hadley circulation strength. We conclude that the Australian Monsoon underwent a major re-organization across the MPT and that extratropical feedbacks were instrumental in driving short- and long-term variability.
Collapse
Affiliation(s)
- Li Gong
- Institute of Geosciences, Christian-Albrechts-University, D-24118, Kiel, Germany
| | - Ann Holbourn
- Institute of Geosciences, Christian-Albrechts-University, D-24118, Kiel, Germany.
| | - Wolfgang Kuhnt
- Institute of Geosciences, Christian-Albrechts-University, D-24118, Kiel, Germany
| | - Bradley Opdyke
- Research School of Earth Sciences, Australian National University, Mills Road, Acton, ACT, 2601, Australia
| | - Yan Zhang
- Ocean Sciences Department, University of California, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Ana Christina Ravelo
- Ocean Sciences Department, University of California, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Peng Zhang
- Institute of Cenozoic Geology and Environment, State Key Laboratory of Continental Dynamics and Department of Geology, Northwest University, 710069, Xi'an, China
| | - Jian Xu
- Institute of Cenozoic Geology and Environment, State Key Laboratory of Continental Dynamics and Department of Geology, Northwest University, 710069, Xi'an, China
| | - Kenji Matsuzaki
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba, 277-8564, Japan
- Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Ivano Aiello
- Department of Geological Oceanography, Moss Landing Marine Laboratories, San Jose State University, Moss Landing, CA, 95039, USA
| | - Sebastian Beil
- Institute of Geosciences, Christian-Albrechts-University, D-24118, Kiel, Germany
| | - Nils Andersen
- Leibniz Laboratory for Radiometric Dating and Stable Isotope Research, Christian-Albrechts-University Kiel, D-24118, Kiel, Germany
| |
Collapse
|
3
|
Antiphase response of the Indonesian-Australian monsoon to millennial-scale events of the last glacial period. Sci Rep 2022; 12:20214. [PMID: 36424387 PMCID: PMC9691635 DOI: 10.1038/s41598-022-21843-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 10/04/2022] [Indexed: 11/27/2022] Open
Abstract
Antiphase behaviour of monsoon systems in alternate hemispheres is well established at yearly and orbital scales in response to alternating sensible heating of continental landmasses. At intermediate timescales without a sensible heating mechanism both in-phase and antiphase behaviours of northern and southern hemisphere monsoon systems are recorded at different places and timescales. At present, there is no continuous, high resolution, precisely dated record of millennial-scale variability of the Indonesian-Australian monsoon during the last glacial period with which to test theories of paleomonsoon behaviour. Here, we present an extension of the Liang Luar, Flores, speleothem δ18O record of past changes in southern hemisphere summer monsoon intensity back to 55.7 kyr BP. Negative δ18O excursions (stronger monsoon) occur during Heinrich events whereas positive excursions (weaker monsoon) occur during Dansgaard-Oeschger interstadials-a first order antiphase relationship with northern hemisphere summer monsoon records. An association of negative δ18O excursions with speleothem growth phases in Liang Luar suggests that these stronger monsoons are related to higher rainfall amounts. However, the response to millennial-scale variability is inconsistent, including a particularly weak response to Heinrich event 3. We suggest that additional drivers such as underlying orbital-scale variability and drip hydrology influence the δ18O response.
Collapse
|
4
|
Hapsari KA, Jennerjahn T, Nugroho SH, Yulianto E, Behling H. Sea level rise and climate change acting as interactive stressors on development and dynamics of tropical peatlands in coastal Sumatra and South Borneo since the Last Glacial Maximum. GLOBAL CHANGE BIOLOGY 2022; 28:3459-3479. [PMID: 35312144 DOI: 10.1111/gcb.16131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 12/15/2021] [Accepted: 01/18/2022] [Indexed: 06/14/2023]
Abstract
Southeast Asian peatlands, along with their various important ecosystem services, are mainly distributed in the coastal areas of Sumatra and Borneo. These ecosystems are threatened by coastal development, global warming and sea level rise (SLR). Despite receiving growing attention for their biodiversity and as massive carbon stores, there is still a lack of knowledge on how they initiated and evolved over time, and how they responded to past environmental change, that is, precipitation, sea level and early anthropogenic activities. To improve our understanding thereof, we conducted multi-proxy paleoecological studies in the Kampar Peninsula and Katingan peatlands in the coastal area of Riau and Central Kalimantan, Indonesia. The results indicate that the initiation timing and environment of both peatlands are very distinct, suggesting that peat could form under various vegetation as soon as there is sufficient moisture to limit organic matter decomposition. The past dynamics of both peatlands were mainly attributable to natural drivers, while anthropogenic activities were hardly relevant. Changes in precipitation and sea level led to shifts in peat swamp forest vegetation, peat accumulation rates and fire regimes at both sites. We infer that the simultaneous occurrence of El Niño-Southern Oscillation (ENSO) events and SLR resulted in synergistic effects which led to the occurrence of severe fires in a pristine coastal peatland ecosystem; however, it did not interrupt peat accretion. In the future, SLR, combined with the projected increase in frequency and intensity of ENSO, can potentially amplify the negative effects of anthropogenic peatland fires. This prospectively stimulates massive carbon release, thus could, in turn, contribute to worsening the global climate crisis especially once an as yet unknown threshold is crossed and peat accretion is halted, that is, peatlands lose their carbon sink function. Given the current rapid SLR, coastal peatland managements should start develop fire risk reduction or mitigation strategies.
Collapse
Affiliation(s)
- K Anggi Hapsari
- Department of Palynology and Climate Dynamics, University of Goettingen, Goettingen, Germany
| | - Tim Jennerjahn
- Department of Biogeochemistry and Geology, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
- Faculty of Geoscience, University of Bremen, Bremen, Germany
| | - Septriono Hari Nugroho
- Research Center for Geotechnology, National Research and Innovation Agency (BRIN), Bandung, Indonesia
| | - Eko Yulianto
- Research Center for Geotechnology, National Research and Innovation Agency (BRIN), Bandung, Indonesia
| | - Hermann Behling
- Department of Palynology and Climate Dynamics, University of Goettingen, Goettingen, Germany
| |
Collapse
|
5
|
Increased fluvial runoff terminated inorganic aragonite precipitation on the Northwest Shelf of Australia during the early Holocene. Sci Rep 2019; 9:18356. [PMID: 31797994 PMCID: PMC6892919 DOI: 10.1038/s41598-019-54981-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 11/07/2019] [Indexed: 11/20/2022] Open
Abstract
Inorganic precipitation of aragonite is a common process within tropical carbonate environments. Across the Northwest Shelf of Australia (NWS) such precipitates were abundant in the late Pleistocene, whereas present-day sedimentation is dominated by calcitic bioclasts. This study presents sedimentological and geochemical analyses of core data retrieved from the upper 13 meters of IODP Site U1461 that provide a high-resolution sedimentary record of the last ~15 thousand years. Sediments that formed from 15 to 10.1 ka BP are aragonitic and characterised by small needles (<5 µm) and ooids. XRF elemental proxy data indicate that these sediments developed under arid conditions in which high marine alkalinity favoured carbonate precipitation. A pronounced change of XRF-proxy values around 10.1 ka BP indicates a transition to a more humid climate and elevated fluvial runoff. This climatic change coincides with a shelf-wide cessation of inorganic aragonite production and a switch to carbonate sedimentation dominated by skeletal calcite. High ocean water alkalinity due to an arid climate and low fluvial runoff therefore seems to be a prerequisite for the formation of shallow water aragonite-rich sediments on the NWS. These conditions are not necessarily synchronous to interglacial periods, but are linked to the regional hydrological cycle.
Collapse
|
6
|
DiNezio PN, Tierney JE, Otto-Bliesner BL, Timmermann A, Bhattacharya T, Rosenbloom N, Brady E. Glacial changes in tropical climate amplified by the Indian Ocean. SCIENCE ADVANCES 2018; 4:eaat9658. [PMID: 30547084 PMCID: PMC6291310 DOI: 10.1126/sciadv.aat9658] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 11/14/2018] [Indexed: 05/26/2023]
Abstract
The mechanisms driving glacial-interglacial changes in the climate of the Indo-Pacific warm pool are poorly understood. Here, we address this question by combining paleoclimate proxies with model simulations of the Last Glacial Maximum climate. We find evidence of two mechanisms explaining key patterns of ocean cooling and rainfall change interpreted from proxy data. Exposure of the Sahul shelf excites a positive ocean-atmosphere feedback involving a stronger surface temperature gradient along the equatorial Indian Ocean and a weaker Walker circulation-a response explaining the drier/wetter dipole across the basin. Northern Hemisphere cooling by ice sheet albedo drives a monsoonal retreat across Africa and the Arabian Peninsula-a response that triggers a weakening of the Indian monsoon via cooling of the Arabian Sea and associated reductions in moisture supply. These results demonstrate the importance of air-sea interactions in the Indian Ocean, amplifying externally forced climate changes over a large part of the tropics.
Collapse
Affiliation(s)
- Pedro N. DiNezio
- Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, J.J. Pickle Research Campus, Building 196 10100 Burnet Road (R2200), Austin, TX 78758, USA
| | - Jessica E. Tierney
- Department of Geosciences, The University of Arizona, 1040 E 4th Street, Tucson, AZ 85721, USA
| | - Bette L. Otto-Bliesner
- National Center for Atmospheric Research, Climate and Global Dynamics Laboratory, 1850 Table Mesa Drive, Boulder, CO 80305, USA
| | - Axel Timmermann
- Center for Climate Physics, Institute for Basic Science, Busandaehak-ro 63beon-gil 2, Geumjeong-gu, Busan 46241, South Korea
- Pusan National University, Busandaehak-ro 63beon-gil 2, Geumjeong-gu, Busan 46241, South Korea
| | - Tripti Bhattacharya
- Department of Earth Science, Syracuse University, 204 Heroy Geology Laboratory, Syracuse, NY 13244-1070, USA
| | - Nan Rosenbloom
- National Center for Atmospheric Research, Climate and Global Dynamics Laboratory, 1850 Table Mesa Drive, Boulder, CO 80305, USA
| | - Esther Brady
- National Center for Atmospheric Research, Climate and Global Dynamics Laboratory, 1850 Table Mesa Drive, Boulder, CO 80305, USA
| |
Collapse
|
7
|
Groeneveld J, Henderiks J, Renema W, McHugh CM, De Vleeschouwer D, Christensen BA, Fulthorpe CS, Reuning L, Gallagher SJ, Bogus K, Auer G, Ishiwa T. Australian shelf sediments reveal shifts in Miocene Southern Hemisphere westerlies. SCIENCE ADVANCES 2017; 3:e1602567. [PMID: 28508066 PMCID: PMC5425240 DOI: 10.1126/sciadv.1602567] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 03/09/2017] [Indexed: 05/10/2023]
Abstract
Global climate underwent a major reorganization when the Antarctic ice sheet expanded ~14 million years ago (Ma) (1). This event affected global atmospheric circulation, including the strength and position of the westerlies and the Intertropical Convergence Zone (ITCZ), and, therefore, precipitation patterns (2-5). We present new shallow-marine sediment records from the continental shelf of Australia (International Ocean Discovery Program Sites U1459 and U1464) providing the first empirical evidence linking high-latitude cooling around Antarctica to climate change in the (sub)tropics during the Miocene. We show that Western Australia was arid during most of the Middle Miocene. Southwest Australia became wetter during the Late Miocene, creating a climate gradient with the arid interior, whereas northwest Australia remained arid throughout. Precipitation and river runoff in southwest Australia gradually increased from 12 to 8 Ma, which we relate to a northward migration or intensification of the westerlies possibly due to increased sea ice in the Southern Ocean (5). Abrupt aridification indicates that the westerlies shifted back to a position south of Australia after 8 Ma. Our midlatitude Southern Hemisphere data are consistent with the inference that expansion of sea ice around Antarctica resulted in a northward movement of the westerlies. In turn, this may have pushed tropical atmospheric circulation and the ITCZ northward, shifting the main precipitation belt over large parts of Southeast Asia (4).
Collapse
Affiliation(s)
- Jeroen Groeneveld
- MARUM–Center for Marine and Environmental Sciences, Department of Geosciences, University of Bremen, 28359 Bremen, Germany
- Corresponding author.
| | - Jorijntje Henderiks
- Department of Earth Sciences, Uppsala University, Villavägen 16, 75236 Uppsala, Sweden
| | - Willem Renema
- Naturalis Biodiversity Center, PO Box 9517, 2300 RA Leiden, Netherlands
| | - Cecilia M. McHugh
- School of Earth and Environmental Sciences, Queens College (City University of New York), 65-30 Kissena Boulevard, Flushing, NY 11367, USA
| | - David De Vleeschouwer
- MARUM–Center for Marine and Environmental Sciences, Department of Geosciences, University of Bremen, 28359 Bremen, Germany
| | - Beth A. Christensen
- Environmental Studies, Adelphi University, 1 South Avenue SCB 201, Garden City, NY 11530, USA
| | - Craig S. Fulthorpe
- Institute for Geophysics, University of Texas at Austin, 10100 Burnet Road (R2200), Austin, TX 78758–4445, USA
| | - Lars Reuning
- Energy and Mineral Resources Group (EMR), Geological Institute Rheinisch-Westfälische Technische Hochschule (RWTH), Aachen University, Wuellnerstrasse, Aachen 52056, Germany
| | - Stephen J. Gallagher
- School of Earth Sciences, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Kara Bogus
- International Ocean Discovery Program, Texas A&M University, 1000 Discovery Drive, College Station, TX 77845–9547, USA
| | - Gerald Auer
- Institute of Earth Sciences, University of Graz, Heinrichstrasse 26, Graz 8010, Austria
| | - Takeshige Ishiwa
- Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8564, Japan
| | | |
Collapse
|
8
|
Extensive wet episodes in Late Glacial Australia resulting from high-latitude forcings. Sci Rep 2017; 7:44054. [PMID: 31004127 PMCID: PMC5341032 DOI: 10.1038/srep44054] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 02/03/2017] [Indexed: 11/08/2022] Open
Abstract
Millennial-scale cooling events termed Heinrich Stadials punctuated Northern Hemisphere climate during the last glacial period. Latitudinal shifts of the intertropical convergence zone (ITCZ) are thought to have rapidly propagated these abrupt climatic signals southward, influencing the evolution of Southern Hemisphere climates and contributing to major reorganisation of the global ocean-atmosphere system. Here, we use neodymium isotopes from a marine sediment core to reconstruct the hydroclimatic evolution of subtropical Australia between 90 to 20 thousand years ago. We find a strong correlation between our sediment provenance proxy data and records for western Pacific tropical precipitations and Australian palaeolakes, which indicates that Northern Hemisphere cooling phases were accompanied by pronounced excursions of the ITCZ and associated rainfall as far south as about 32°S. Comparatively, however, each of these humid periods lasted substantially longer than the mean duration of Heinrich Stadials, overlapping with subsequent warming phases of the southern high-latitudes recorded in Antarctic ice cores. In addition to ITCZ-driven hydroclimate forcing, we infer that changes in Southern Ocean climate also played an important role in regulating late glacial atmospheric patterns of the Southern Hemisphere subtropical regions.
Collapse
|