1
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Zhou Y, McManus JF. Heinrich event ice discharge and the fate of the Atlantic Meridional Overturning Circulation. Science 2024; 384:983-986. [PMID: 38815028 DOI: 10.1126/science.adh8369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 04/30/2024] [Indexed: 06/01/2024]
Abstract
During Heinrich events, great armadas of icebergs episodically flooded the North Atlantic Ocean and weakened overturning circulation. The ice discharges of these episodes constrain the sensitivity of overturning circulation to iceberg melting. We reconstructed these ice discharges to be as high as 0.13 sverdrup (Sv) (1 Sv = 1 million cubic meters per second) during Heinrich event 4 and to average 0.029 Sv over all episodes. The present-day Greenland Ice Sheet calving of icebergs is comparable to that of a mid-range Heinrich event. As the future Greenland Ice Sheet recedes from marine-terminating outlets, its iceberg calving likely will not persist long enough for icebergs alone to cause catastrophic disruption to the Atlantic overturning circulation, although the accelerating Greenland runoff and continued global warming remain threats to the circulation stability.
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Affiliation(s)
- Yuxin Zhou
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, USA
| | - Jerry F McManus
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, USA
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2
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Fastovich D, Radeloff VC, Zuckerberg B, Williams JW. Legacies of millennial-scale climate oscillations in contemporary biodiversity in eastern North America. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230012. [PMID: 38583476 PMCID: PMC10999273 DOI: 10.1098/rstb.2023.0012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 01/22/2024] [Indexed: 04/09/2024] Open
Abstract
The Atlantic meridional overturning circulation (AMOC) has caused significant climate changes over the past 90 000 years. Prior work has hypothesized that these millennial-scale climate variations effected past and contemporary biodiversity, but the effects are understudied. Moreover, few biogeographic models have accounted for uncertainties in palaeoclimatic simulations of millennial-scale variability. We examine whether refuges from millennial-scale climate oscillations have left detectable legacies in the patterns of contemporary species richness in eastern North America. We analyse 13 palaeoclimate estimates from climate simulations and proxy-based reconstructions as predictors for the contemporary richness of amphibians, passerine birds, mammals, reptiles and trees. Results suggest that past climate changes owing to AMOC variations have left weak but detectable imprints on the contemporary richness of mammals and trees. High temperature stability, precipitation increase, and an apparent climate fulcrum in the southeastern United States across millennial-scale climate oscillations aligns with high biodiversity in the region. These findings support the hypothesis that the southeastern United States may have acted as a biodiversity refuge. However, for some taxa, the strength and direction of palaeoclimate-richness relationships varies among different palaeoclimate estimates, pointing to the importance of palaeoclimatic ensembles and the need for caution when basing biogeographic interpretations on individual palaeoclimate simulations. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.
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Affiliation(s)
- David Fastovich
- Department of Geography, University of Wisconsin–Madison, 550 North Park Street, Madison, WI 53706, USA
- Department of Earth and Environmental Sciences, Syracuse University, 141 Crouse Drive, Syracuse, NY 13210, USA
| | - Volker C. Radeloff
- SILVIS Laboratory, Department of Forest and Wildlife Ecology, University of Wisconsin–Madison, 1630 Linden Drive, Madison, WI 53706, USA
| | - Benjamin Zuckerberg
- Department of Forest and Wildlife Ecology, University of Wisconsin–Madison, 1630 Linden Drive, Madison, WI 53706, USA
| | - John W. Williams
- Department of Geography, University of Wisconsin–Madison, 550 North Park Street, Madison, WI 53706, USA
- Center for Climatic Research, University of Wisconsin–Madison, 550 North Park Street, Madison, WI 53706, USA
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3
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Tan L, Cheng H, Li D, Orozbaev R, Li Y, Xu H, Edwards RL, Song Y, Ma L, Lin F, Sinha A, An Z. Hydroclimatic changes on multiple timescales since 7800 y BP in the winter precipitation-dominated Central Asia. Proc Natl Acad Sci U S A 2024; 121:e2321645121. [PMID: 38527201 PMCID: PMC10998633 DOI: 10.1073/pnas.2321645121] [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: 12/08/2023] [Accepted: 02/22/2024] [Indexed: 03/27/2024] Open
Abstract
Central Asia (CA) is one of the world's most significant arid regions, which is markedly impacted by global warming. A better understanding of the dynamical processes governing its Holocene climate variability is critical for a better understanding of possible future impacts of climate change in the region. To date, most of the existing CA paleoclimate records are from the summer precipitation-dominated eastern CA (ECA), with few records from the winter precipitation-dominated western CA (WCA). Here, we present a precisely dated (~6‰) and highly resolved (<4-y) record of hydroclimatic variations from the WCA covering the period between 7,774 and 656 y BP. Utilizing multiple proxies (δ18O, δ13C, and Sr/Ca) derived from a stalagmite from the Fergana Valley, Kyrgyzstan, we reveal a long-term drying trend in WCA, which is in contrast with the wetting trend in ECA. We propose that different responses of winter and summer westerly jets to seasonal solar insolation over the past 8,000 y may have resulted in an antiphased precipitation relationship between the WCA and ECA. Our data contain dominant quasiperiodicities of 1,400, 50 to 70, and 20 to 30 y, indicating close connections between the WCA climate and the North Atlantic. We further identified a series of droughts and pluvials on centennial-to-decadal timescales, which may have influenced regional societies and trans-Eurasian culture exchanges during historical and prehistorical times.
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Affiliation(s)
- Liangcheng Tan
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
- Institute of Global Environmental Change, Xi’an Jiaotong University, Xi’an710054, China
| | - Hai Cheng
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
- Institute of Global Environmental Change, Xi’an Jiaotong University, Xi’an710054, China
| | - Dong Li
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
- Library of Chang’an University, Xi’an710064, China
| | - Rustam Orozbaev
- Research Center for Ecology and Environment of Central Asia (Bishkek), Chinese Academy of Sciences, Bishkek720040, Kyrgyzstan
- Institute of Geology, National Academy of Sciences of Kyrgyz Republic, Bishkek720040, Kyrgyzstan
| | - Yanzhen Li
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
| | - Hai Xu
- Institute of Surface-Earth System Science, Tianjin University, Tianjin300072, China
| | - R. Lawrence Edwards
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN55455
| | - Yougui Song
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
| | - Le Ma
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
| | - Fangyuan Lin
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
| | - Ashish Sinha
- Department of Earth Science, California State University, Dominguez Hills, Carson, CA90747
| | - Zhisheng An
- State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an710061, China
- Interdisciplinary Research Center of Earth Science Frontier, Beijing Normal University, Beijing100875, China
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4
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Fan B, Lu H, Li Y, Shen C, Xu Q, Zhang J, Huan X, Wang Y, Wang N, Xu D, Dong Y, Cui A, Wu N. A novel approach for quantitatively distinguishing between anthropogenic and natural effects on paleovegetation. PNAS NEXUS 2024; 3:pgae135. [PMID: 38617585 PMCID: PMC11010655 DOI: 10.1093/pnasnexus/pgae135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 03/21/2024] [Indexed: 04/16/2024]
Abstract
How to distinguish and quantify past human impacts on vegetation is a significant challenge in paleoecology. Here, we propose a novel method, the error inflection point-discriminant technique. It finds out the inflection points (IPs) of the regression errors of pollen-climate transfer functions using modern pollen spectra from vegetation with different values of the Human Influence Index (HII), which represent the HII threshold values of native/secondary and secondary/artificial vegetation systems. Our results show that the HII value at the native/secondary vegetation IPs is approximately 22 and globally uniform, whereas it varies regionally for the secondary/artificial vegetation IPs. In a case study of the Liangzhu archaeological site in the lower Yangtze River, discriminant functions for pollen spectra from three vegetation types and pollen-climate transfer functions of the native vegetation were established to reconstruct paleovegetation and paleoclimate over the past 6,600 years. Our study demonstrates this method's feasibility for quantitatively distinguishing human impacts on paleovegetation and assessing quantitative paleoclimate reconstructions using pollen data.
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Affiliation(s)
- Baoshuo Fan
- Hebei Key Laboratory of Environmental Change and Ecological Construction, College of Geographical Sciences, Hebei Normal University, Shijiazhuang 050024, PR China
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
| | - Houyuan Lu
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
- University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yuecong Li
- Hebei Key Laboratory of Environmental Change and Ecological Construction, College of Geographical Sciences, Hebei Normal University, Shijiazhuang 050024, PR China
| | - Caiming Shen
- Yunnan Key Laboratory of Plateau Geographical Processes and Environmental Changes, Faculty of Geography, Yunnan Normal University, Kunming 650500, PR China
| | - Qinghai Xu
- Hebei Key Laboratory of Environmental Change and Ecological Construction, College of Geographical Sciences, Hebei Normal University, Shijiazhuang 050024, PR China
| | - Jianping Zhang
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
| | - Xiujia Huan
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
- Shandong Provincial Key Laboratory of Soil Conservation and Environmental Protection, School of Resources and Environment, Linyi University, Linyi 276000, PR China
| | - Yonglei Wang
- Zhejiang Provincial Institute of Relics and Archaeology, Hangzhou 310014, PR China
| | - Ningyuan Wang
- Zhejiang Provincial Institute of Relics and Archaeology, Hangzhou 310014, PR China
| | - Deke Xu
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
| | - Yajie Dong
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
| | - Anning Cui
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
| | - Naiqin Wu
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, PR China
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5
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Chen F, Mao S, Li G, Tian Y, Miao L, Xu W, Zhu X, Yan W. Anthropogenic multipollutant input to the offshore South China Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170228. [PMID: 38272085 DOI: 10.1016/j.scitotenv.2024.170228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/27/2024]
Abstract
The remote region of the South China Sea (SCS), situated far from urban mainland areas, is commonly perceived to experience minimal pollution. However, this may evolve into a considerably polluted region owing to increasing anthropogenic pollutants. In this study, we employ a multidisciplinary approach to analyze the surface sediments collected from the offshore area of the southern SCS. Our aim is to explore potential anthropogenic pollutants, their interactions, and the related controlling factors. This research endeavors to enhance our understanding of the current pollution status in the SCS and help making relevant policy management decisions. Comparison with previous reports reveals that now, the area is more extensively and increasingly contaminated by petroleum hydrocarbons and heavy metals (Cd and As) than before. For the first time, we report the recognition of coprostanol and long-chain alkyl mid-chain ketones, unveiling the noticeable incorporation of sewage fecal matter and biomass burning into offshore sediments. Moreover, sedimentary multipollutants (except ketones) exhibit strong correlations with terrestrial elements and fine-sized particles, displaying a roughly high-west/low-east spatial variability in pollutant accumulation or enrichment. These signatures evidently demonstrate the major impact of river discharges (e.g., the Mekong River to the west and the Pearl and Red Rivers to the north) on the SCS. They have hydrodynamic effects on the subsequent basin-wide dispersal of pollutants, driven by monsoon-induced large- and regional-scale currents. The different behavior of burning-related ketones may be partly due to their aerosol form, leading to atmospheric transportation. Because anthropogenic multipollutants pose compounded threats, exacerbating oceanic warming and acidification to marine ecosystems such as the widespread coral reefs in the southern SCS, scientific management of urban emissions is required to mitigate ecosystem degradation in the Anthropocene era.
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Affiliation(s)
- Fen Chen
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shengyi Mao
- Key Laboratory of Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Gang Li
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Yuhang Tian
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Li Miao
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Weihai Xu
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Xiaowei Zhu
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
| | - Wen Yan
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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6
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Dawson RR, Burns SJ, Tiger BH, McGee D, Faina P, Scroxton N, Godfrey LR, Ranivoharimanana L. Zonal control on Holocene precipitation in northwestern Madagascar based on a stalagmite from Anjohibe. Sci Rep 2024; 14:5496. [PMID: 38448499 PMCID: PMC10917758 DOI: 10.1038/s41598-024-55909-6] [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: 08/02/2023] [Accepted: 02/28/2024] [Indexed: 03/08/2024] Open
Abstract
The Malagasy Summer Monsoon is an important part of the larger Indian Ocean and tropical monsoon region. As the effects of global warming play out, changes to precipitation in Madagascar will have important ramifications for the Malagasy people. To help understand how precipitation responds to climate changes we present a long-term Holocene speleothem record from Anjohibe, part of the Andranoboka cave system in northwestern Madagascar. To date, it is the most complete Holocene record from this region and sheds light on the nature of millennial and centennial precipitation changes in this region. We find that over the Holocene, precipitation in northwestern Madagascar is actually in phase with the Northern Hemisphere Asian monsoon on multi-millennial scales, but that during some shorter centennial-scale events such as the 8.2 ka event, Anjohibe exhibits an antiphase precipitation signal to the Northern Hemisphere. The ultimate driver of precipitation changes across the Holocene does not appear to be the meridional migration of the monsoon. Instead, zonal sea surface temperature gradients in the Indian Ocean seem to play a primary role in precipitation changes in northwestern Madagascar.
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Affiliation(s)
- Robin R Dawson
- Department of Earth, Geographic and Climate Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA.
| | - Stephen J Burns
- Department of Earth, Geographic and Climate Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Benjamin H Tiger
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - David McGee
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Peterson Faina
- The Climate School, Columbia University, New York, NY, 10025, USA
| | - Nick Scroxton
- Irish Climate Analysis and Research Units, Department of Geography, Maynooth University, Maynooth, Ireland
| | - Laurie R Godfrey
- Department of Anthropology, University of Massachusetts, Amherst, MA, 01003, USA
| | - Lovasoa Ranivoharimanana
- Mention Bassins Sédimentaires, Evolution, Conservation, Faculté des Sciences, Université D'Antananarivo, Antananarivo, Madagascar
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7
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Guo J, Ziegler M, Wanders N, Vreeken M, Yin Q, Lu H, Fuchs L, Dong J, Sun Y, Peterse F. Robust land surface temperature record for north China over the past 21,000 years. SCIENCE ADVANCES 2024; 10:eadj4800. [PMID: 38381815 PMCID: PMC10881045 DOI: 10.1126/sciadv.adj4800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 01/17/2024] [Indexed: 02/23/2024]
Abstract
Numerous proxy reconstructions have provided general insight into late Quaternary East Asian Monsoon variability. However, challenges persist in precisely assessing absolute temperature impacts on proxy variations. Here, we use two independent paleothermometers, based on bacterial membrane lipids and clumped isotopes of snail shells, in the same section of the western Chinese Loess Plateau to establish a robust land surface temperature record spanning the past approximately 21,000 years. Our independent temperature records consistently reveal (i) similar land surface temperatures between the Last Glacial Maximum and late Holocene and (ii) a gradual cooling Holocene, which contrasts with the climate model predictions. We propose that changes in soil moisture availability over the deglaciation modulates the land surface temperature recorded by the proxies. A land surface energy partitioning model confirms this mechanism, suggesting that effects of soil moisture availability should be properly considered when comparing proxy records with climate model outputs.
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Affiliation(s)
- Jingjing Guo
- Department of Earth Sciences, Utrecht University, 3584 CB Utrecht, Netherlands
| | - Martin Ziegler
- Department of Earth Sciences, Utrecht University, 3584 CB Utrecht, Netherlands
| | - Niko Wanders
- Department of Physical Geography, Utrecht University, 3584 CB Utrecht, Netherlands
| | - Mike Vreeken
- Department of Earth Sciences, Utrecht University, 3584 CB Utrecht, Netherlands
| | - Qiuzhen Yin
- Earth and Climate Research Center, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Hao Lu
- Department of Earth Sciences, Utrecht University, 3584 CB Utrecht, Netherlands
| | - Louise Fuchs
- Department of Earth Sciences, Utrecht University, 3584 CB Utrecht, Netherlands
| | - Jibao Dong
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
| | - Youbin Sun
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
| | - Francien Peterse
- Department of Earth Sciences, Utrecht University, 3584 CB Utrecht, Netherlands
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8
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Held F, Cheng H, Edwards RL, Tüysüz O, Koç K, Fleitmann D. Dansgaard-Oeschger cycles of the penultimate and last glacial period recorded in stalagmites from Türkiye. Nat Commun 2024; 15:1183. [PMID: 38331936 PMCID: PMC10853552 DOI: 10.1038/s41467-024-45507-5] [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: 05/23/2023] [Accepted: 01/19/2024] [Indexed: 02/10/2024] Open
Abstract
The last glacial period is characterized by abrupt climate oscillations, also known as Dansgaard-Oeschger (D-O) cycles. However, D-O cycles remain poorly documented in climate proxy records covering the penultimate glacial period. Here we present highly resolved and precisely dated speleothem time series from Sofular Cave in northern Türkiye to provide clear evidence for D-O cycles during Marine Isotope Stage (MIS) 6 as well as MIS 2-4. D-O cycles are most clearly expressed in the Sofular carbon isotope time series, which correlate inversely with regional sea surface temperature (SST) records from the Black Sea. The pacing of D-O cycles is almost twice as long during MIS 6 compared to MIS 2-4, and could be related to a weaker Atlantic Meridional Overturning Circulation (AMOC) and a different mean climate during MIS 6 compared to MIS 2-4, leading most likely to a higher threshold for the occurrence of D-O cycles.
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Affiliation(s)
- F Held
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland.
| | - H Cheng
- Institute of Global Environmental Change, Xi'an Jiaotong University, 710054, Xi'an, China
| | - R L Edwards
- Department of Earth and Environmental Sciences, University of Minnesota, 55455, Minneapolis, USA
| | - O Tüysüz
- Eurasia Institute of Earth Sciences, Istanbul Technical University, 34469, Istanbul, Türkiye
| | - K Koç
- Department of Geological Engineering, Akdeniz University, 07058, Antalya, Türkiye
| | - D Fleitmann
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland.
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9
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Liu Z, Bao Y, Thompson LG, Mosley-Thompson E, Tabor C, Zhang GJ, Yan M, Lofverstrom M, Montanez I, Oster J. Tropical mountain ice core δ 18O: A Goldilocks indicator for global temperature change. SCIENCE ADVANCES 2023; 9:eadi6725. [PMID: 37939192 PMCID: PMC10631737 DOI: 10.1126/sciadv.adi6725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 10/12/2023] [Indexed: 11/10/2023]
Abstract
Very high tropical alpine ice cores provide a distinct paleoclimate record for climate changes in the middle and upper troposphere. However, the climatic interpretation of a key proxy, the stable water oxygen isotopic ratio in ice cores (δ18Oice), remains an outstanding problem. Here, combining proxy records with climate models, modern satellite measurements, and radiative-convective equilibrium theory, we show that the tropical δ18Oice is an indicator of the temperature of the middle and upper troposphere, with a glacial cooling of -7.35° ± 1.1°C (66% CI). Moreover, it severs as a "Goldilocks-type" indicator of global mean surface temperature change, providing the first estimate of glacial stage cooling that is independent of marine proxies as -5.9° ± 1.2°C. Combined with all estimations available gives the maximum likelihood estimate of glacial cooling as -5.85° ± 0.51°C.
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Affiliation(s)
- Zhengyu Liu
- Department of Geography, Ohio State University, Columbus, OH, USA
- School of Geography Science, Nanjing Normal University, Nanjing, China
- Byrd Polar and Climate Research Center, Ohio State University, Columbus, OH, USA
| | - Yuntao Bao
- Department of Geography, Ohio State University, Columbus, OH, USA
| | - Lonnie G. Thompson
- Byrd Polar and Climate Research Center, Ohio State University, Columbus, OH, USA
- School of Earth Sciences, Ohio State University, Columbus, OH, USA
| | - Ellen Mosley-Thompson
- Department of Geography, Ohio State University, Columbus, OH, USA
- Byrd Polar and Climate Research Center, Ohio State University, Columbus, OH, USA
| | - Clay Tabor
- Department of Earth Sciences, University of Connecticut, Storrs, CT, USA
| | - Guang J. Zhang
- Scripps Institute of Oceanography, University of California, San Diego, San Diego, CA, USA
| | - Mi Yan
- School of Geography Science, Nanjing Normal University, Nanjing, China
| | | | - Isabel Montanez
- Department of Earth and Planetary Sciences, University of California–Davis, Davis, CA, USA
| | - Jessica Oster
- Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN, USA
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10
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Martin KC, Buizert C, Edwards JS, Kalk ML, Riddell-Young B, Brook EJ, Beaudette R, Severinghaus JP, Sowers TA. Bipolar impact and phasing of Heinrich-type climate variability. Nature 2023; 617:100-104. [PMID: 37095266 DOI: 10.1038/s41586-023-05875-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 02/09/2023] [Indexed: 04/26/2023]
Abstract
During the last ice age, the Laurentide Ice Sheet exhibited extreme iceberg discharge events that are recorded in North Atlantic sediments1. These Heinrich events have far-reaching climate impacts, including widespread disruptions to hydrological and biogeochemical cycles2-4. They occurred during Heinrich stadials-cold periods with strongly weakened Atlantic overturning circulation5-7. Heinrich-type variability is not distinctive in Greenland water isotope ratios, a well-dated site temperature proxy8, complicating efforts to assess their regional climate impact and phasing against Antarctic climate change. Here we show that Heinrich events have no detectable temperature impact on Greenland and cooling occurs at the onset of several Heinrich stadials, and that both types of Heinrich variability have a distinct imprint on Antarctic climate. Antarctic ice cores show accelerated warming that is synchronous with increases in methane during Heinrich events, suggesting an atmospheric teleconnection9, despite the absence of a Greenland climate signal. Greenland ice-core nitrogen stable isotope ratios, a sensitive temperature proxy, indicate an abrupt cooling of about three degrees Celsius at the onset of Heinrich Stadial 1 (17.8 thousand years before present, where present is defined as 1950). Antarctic warming lags this cooling by 133 ± 93 years, consistent with an oceanic teleconnection. Paradoxically, proximal sites are less affected by Heinrich events than remote sites, suggesting spatially complex event dynamics.
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Affiliation(s)
- Kaden C Martin
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA.
| | - Christo Buizert
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
| | - Jon S Edwards
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
| | - Michael L Kalk
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
| | - Ben Riddell-Young
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
| | - Edward J Brook
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
| | - Ross Beaudette
- Scripps Institution of Oceanography, University of California, San Diego, CA, USA
| | | | - Todd A Sowers
- Department of Geosciences, Pennsylvania State University, State College, PA, USA
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11
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Bagniewski W, Rousseau DD, Ghil M. The PaleoJump database for abrupt transitions in past climates. Sci Rep 2023; 13:4472. [PMID: 36934110 PMCID: PMC10024733 DOI: 10.1038/s41598-023-30592-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 02/27/2023] [Indexed: 03/20/2023] Open
Abstract
Tipping points (TPs) in Earth's climate system have been the subject of increasing interest and concern in recent years, given the risk that anthropogenic forcing could cause abrupt, potentially irreversible, climate transitions. Paleoclimate records are essential for identifying past TPs and for gaining a thorough understanding of the underlying nonlinearities and bifurcation mechanisms. However, the quality, resolution, and reliability of these records can vary, making it important to carefully select the ones that provide the most accurate representation of past climates. Moreover, as paleoclimate time series vary in their origin, time spans, and periodicities, an objective, automated methodology is crucial for identifying and comparing TPs. To address these challenges, we introduce the open-source PaleoJump database, which contains a collection of carefully selected, high-resolution records originating in ice cores, marine sediments, speleothems, terrestrial records, and lake sediments. These records describe climate variability on centennial, millennial and longer time scales and cover all the continents and ocean basins. We provide an overview of their spatial distribution and discuss the gaps in coverage. Our statistical methodology includes an augmented Kolmogorov-Smirnov test and Recurrence Quantification Analysis; it is applied here, for illustration purposes, to selected records in which abrupt transitions are automatically detected and the presence of potential tipping elements is investigated. These transitions are shown in the PaleoJump database along with other essential information about the records, including location, temporal scale and resolution, as well as temporal plots. This open-source database represents, therefore, a valuable resource for researchers investigating TPs in past climates.
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Affiliation(s)
- Witold Bagniewski
- Department of Geosciences and Laboratoire de Météorologie Dynamique (CNRS and IPSL), École Normale Supérieure, PSL University, Paris, France.
| | - Denis-Didier Rousseau
- Geosciences Montpellier, CNRS, University of Montpellier, Montpellier, France
- Institute of Physics - CSE, Division of Geochronology and Environmental Isotopes, Silesian University of Technology, Gliwice, Poland
- Lamont-Doherty Earth Observatory, Columbia University, New York, USA
| | - Michael Ghil
- Department of Geosciences and Laboratoire de Météorologie Dynamique (CNRS and IPSL), École Normale Supérieure, PSL University, Paris, France
- Department of Atmospheric and Oceanic Sciences, University of California at Los Angeles, Los Angeles, USA
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12
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Zhang X, Zheng Z, Huang K, Cheng J, Cheddadi R, Zhao Y, Liang C, Yang X, Wan Q, Tang Y, Chen C, Li J. Quantification of Asian monsoon variability from 68 ka BP through pollen-based climate reconstruction. Sci Bull (Beijing) 2023; 68:713-722. [PMID: 36934013 DOI: 10.1016/j.scib.2023.03.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/18/2023]
Abstract
The glacial-interglacial variability of precipitation and its driving mechanism in monsoonal regions has long been a subject of debate. However, there are few records of quantitative climate reconstruction dating to the last glacial cycle in areas dominated by the Asian summer monsoon. Here, using a pollen-based quantitative climate reconstruction based on three sites in areas exposed to the Asian summer monsoon, we demonstrate that climate has undergone great variability over the past 68 ka. The differences between the last glacial and the Holocene optimum could have been as much as 35%-51% for precipitation, and 5-7 °C for mean annual temperature. Our findings also reveal regional heterogeneity during the abrupt climate events of Heinrich Event 1 and Younger Dryas, that drove drier conditions in southwestern China dominated by the Indian summer monsoon, and a wetter climate in central eastern China. The pattern of variation in reconstructed precipitation, exhibiting strong glacial-interglacial variability, is broadly consistent with the stalagmite δ18O records from Southwest China and South Asia. Our results of reconstruction quantify the sensitivity of the MIS3 precipitation to orbital insolation changes, and highlight the prominent influence of interhemispheric temperature gradients on Asian monsoon variability. Comparison with transient simulations and major climate forcings has shown that the mode of precipitation variability during the transition from the last glacial maximum to the Holocene has been significantly modulated by weak or collapsed Atlantic meridional overturning circulation events in addition to insolation forcing.
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Affiliation(s)
- Xiao Zhang
- Guangdong Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China
| | - Zhuo Zheng
- Guangdong Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China.
| | - Kangyou Huang
- Guangdong Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China.
| | - Jun Cheng
- Center for Ocean-Atmosphere Interaction Research, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Rachid Cheddadi
- Institute of Evolutionary Sciences of Montpellier, University of Montpellier, Montpellier 34095, France
| | - Yan Zhao
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chen Liang
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Department of Land Resource and Urban Planning, Hebei GEO University, Shijiazhuang 050031, China
| | - Xiaoqiang Yang
- Guangdong Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China
| | - Qiuchi Wan
- Guangdong Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China
| | - Yongjie Tang
- Guangdong Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China
| | - Cong Chen
- Guangdong Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China
| | - Jie Li
- Qingdao Institute of Marine Geology, China Geological Survey, Qingdao 266071, China
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13
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Xu D, Lu H, Chu G, Shen C, Sun Q, Wu J, Li F, Song B, Cui A, Li H, Wu N. Fast response of vegetation in East Asia to abrupt climatic events during the last deglaciation. PNAS NEXUS 2023; 2:pgad061. [PMID: 37007712 PMCID: PMC10062325 DOI: 10.1093/pnasnexus/pgad061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 01/04/2023] [Accepted: 02/14/2023] [Indexed: 04/03/2023]
Abstract
Climate changes had major impacts on the vegetation of East Asia during the last deglaciation. However, the rate and pattern of vegetation succession in response to large-scale climatic events during this interval are controversial. Here, we present well-dated decadal-resolution pollen records from annually laminated Maar Lake Xiaolongwan during the last deglaciation. The vegetation changes were rapid and near-synchronous with millennial-scale climatic events, including Greenland Stadial 2.1a (GS-2.1a), Greenland Interstadial 1 (GI-1), Greenland Stadial 1 (GS-1), and the early Holocene (EH). The vegetation responded in different ways to the different rates of climate change. Vegetation change was gradual [∼1 thousand years (kyr) response time] during the transition between GS-2.1a and GI-1, but it was faster (∼0.4 kyr response time) during the transitions between GI-1, GS-1, and the EH, resulting in different patterns of vegetation succession. Additionally, the amplitude and pattern of vegetation changes resembled those in the records of regional climate change based on long-chain n-alkanes δ13C and stalagmite δ18O, as well as in the mid-latitude Northern Hemisphere temperature record and the Greenland ice core δ18O record. Therefore, the rate and pattern of vegetation succession in the Changbai Mountain of Northeast Asia during the last deglaciation were sensitive to the characteristics of changes in the regional hydrothermal conditions and mid-latitude Northern Hemisphere temperature, which were linked to both high- and low-latitude atmospheric-oceanic dynamics. Overall, our findings reveal a close relationship between ecosystem succession and hydrothermal changes during these millennial-scale climatic events in East Asia during the last deglaciation.
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Affiliation(s)
- Deke Xu
- To whom correspondence should be addressed: ;
| | - Houyuan Lu
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- Innovation Academy for Earth Science, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, No.1 Yanqihu East Rd, Huairou District, Beijing 101408, China
| | - Guoqiang Chu
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- CAS Center for Excellence in Life and Paleoenvironment, No. 142 Xizhimenwai Str, Xicheng District, Beijing 100044, China
| | | | - Qing Sun
- Geoanalysis Center, Chinese Academy of Geological Sciences, No. 26 Baiwanzhuang Str, Xicheng District, Beijing 100037, China
| | - Jing Wu
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- Innovation Academy for Earth Science, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
| | - Fengjiang Li
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- Innovation Academy for Earth Science, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
| | - Bing Song
- Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, No. 73 East Beijing Rd, Xuanwu District, Nanjing 210008, China
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- Innovation Academy for Earth Science, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
| | - Anning Cui
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- Innovation Academy for Earth Science, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
| | - Hao Li
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, No. 19, Beitucheng Western Road, Chaoyang District, Beijing 100029, China
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, No.1 Yanqihu East Rd, Huairou District, Beijing 101408, China
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14
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Du X, Russell JM, Liu Z, Otto-Bliesner BL, Oppo DW, Mohtadi M, Zhu C, Galy VV, Schefuß E, Yan Y, Rosenthal Y, Dubois N, Arbuszewski J, Gao Y. North Atlantic cooling triggered a zonal mode over the Indian Ocean during Heinrich Stadial 1. SCIENCE ADVANCES 2023; 9:eadd4909. [PMID: 36598985 PMCID: PMC9812376 DOI: 10.1126/sciadv.add4909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
Abrupt changes in the Atlantic meridional overturning circulation (AMOC) are thought to affect tropical hydroclimate through adjustment of the latitudinal position of the intertropical convergence zone (ITCZ). Heinrich Stadial 1 (HS1) involves the largest AMOC reduction in recent geological time; however, over the tropical Indian Ocean (IO), proxy records suggest zonal anomalies featuring intense, widespread drought in tropical East Africa versus generally wet but heterogeneous conditions in the Maritime Continent. Here, we synthesize proxy data and an isotope-enabled transient deglacial simulation and show that the southward ITCZ shift over the eastern IO during HS1 strengthens IO Walker circulation, triggering an east-west precipitation dipole across the basin. This dipole reverses the zonal precipitation anomalies caused by the exposed Sunda and Sahul shelves due to glacial lower sea level. Our study illustrates how zonal modes of atmosphere-ocean circulation can amplify or reverse global climate anomalies, highlighting their importance for future climate change.
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Affiliation(s)
- Xiaojing Du
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI, USA
- Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
| | - James M. Russell
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI, USA
- Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
| | - Zhengyu Liu
- Atmospheric Science Program, Department of Geography, The Ohio State University, Columbus, OH, USA
| | - Bette L. Otto-Bliesner
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - Delia W. Oppo
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Mahyar Mohtadi
- MARUM-Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Chenyu Zhu
- Frontier Science Center for Deep Ocean Multispheres and Earth System (FDOMES) and Physical Oceanography Laboratory, Ocean University of China, Qingdao, China
| | - Valier V. Galy
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Enno Schefuß
- MARUM-Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Yan Yan
- State Key Laboratory of Isotope Geochemistry, CAS Center for Excellence in Deep Earth Science, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
| | - Yair Rosenthal
- Department of Marine and Coastal Sciences and Department of Earth and Planetary Sciences, Rutgers, State University of New Jersey, New Brunswick, NJ, USA
| | - Nathalie Dubois
- Department of Surface Waters Research and Management, Eawag, Dübendorf, Switzerland
- Department of Earth Sciences, ETH Zürich, Zürich, Switzerland
| | - Jennifer Arbuszewski
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Yu Gao
- Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China
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15
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Schimmenti D, Marcantonio F, Hayes CT, Hertzberg J, Schmidt M, Sarao J. Insights into the deglacial variability of phytoplankton community structure in the eastern equatorial Pacific Ocean using [ 231Pa/ 230Th]xs and opal-carbonate fluxes. Sci Rep 2022; 12:22258. [PMID: 36564500 PMCID: PMC9789155 DOI: 10.1038/s41598-022-26593-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
Fully and accurately reconstructing changes in oceanic productivity and carbon export and their controls is critical to determining the efficiency of the biological pump and its role in the global carbon cycle through time, particularly in modern CO2 source regions like the eastern equatorial Pacific (EEP). Here we present new high-resolution records of sedimentary 230Th-normalized opal and nannofossil carbonate fluxes and [231Pa/230Th]xs ratios from site MV1014-02-17JC in the Panama Basin. We find that, across the last deglaciation, phytoplankton community structure is driven by changing patterns of nutrient (nitrate, iron, and silica) availability which, in turn, are caused by variability in the position of the Intertropical Convergence Zone (ITCZ) and associated changes in biogeochemical cycling and circulation in the Southern Ocean. Our multi-proxy work suggests greater scrutiny is required in the interpretation of common geochemical proxies of productivity and carbon export in the EEP.
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Affiliation(s)
- Danielle Schimmenti
- grid.264756.40000 0004 4687 2082Department of Geology and Geophysics, Texas A&M University, College Station, TX USA
| | - Franco Marcantonio
- grid.264756.40000 0004 4687 2082Department of Geology and Geophysics, Texas A&M University, College Station, TX USA
| | - Christopher T. Hayes
- grid.267193.80000 0001 2295 628XSchool of Ocean Science and Engineering, University of Southern Mississippi, Stennis Space Center, MS USA
| | | | - Matthew Schmidt
- grid.261368.80000 0001 2164 3177Department of Ocean and Earth Sciences, Old Dominion University, Norfolk, VA USA
| | - John Sarao
- grid.264756.40000 0004 4687 2082Department of Geology and Geophysics, Texas A&M University, College Station, TX USA
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16
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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.
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17
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Huang M, Deng Y, Peng H, Wen Z, Shang G, Guan H, Ma C. Hydroclimatic changes since the Last Glacial Maximum recorded in mountain peat deposit on the southwestern margin of the Sichuan Basin, China. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.1050429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Knowledge of the hydroclimatic changes in Southwest China since the Last Glacial Maximum (LGM) is crucial for disentangling the long-term evolution of the Asia Monsoon and predicting the future fate of the mountain peat deposit in the Asia Monsoon region. In this study, we obtained a 530-cm-long peat core from the Ganchi wetland in Southwest China and analyzed its geochemical indices, including total nitrogen (TN), total organic carbon (TOC), stable carbon isotope composition of organics (δ13Corg), and the concentration of several major elements, to investigate the sedimentary and hydroclimate evolution since the LGM. We found that the peat strata in the Ganchi wetland have developed gradually from 13.7 cal kyr BP, which is likely ascribed to the warm climate during the Bølling-Allerød (B/A) period. TOC, δ13Corg, K/Ti, and Fe/Mn records showed notable paleoclimate shifts since the last deglaciation. The first warming period after the LGM was observed starting at 18.2 cal kyr BP, which is consistent with other records from Southwest China. The reconstruction results show that the western margin of the Sichuan Basin during the last deglaciation was most affected by the East Asia summer monsoon (EASM), and less affected by the Indian summer monsoon (ISM). The climate of the early Holocene (11.2–7.5 cal kyr BP) was affected by both the ISM and EASM, resulting in more complex local climatic features. The Holocene Megathermal period observed from 7.5 to 3.5 cal kyr BP, is consistent with the timing detected in other records of Southwest China.
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Zhao C, Wang Y, Walden JP. Diachronic shifts in lithic technological transmission between the eastern Eurasian Steppe and northern China in the Late Pleistocene. PLoS One 2022; 17:e0275162. [PMID: 36327263 PMCID: PMC9632798 DOI: 10.1371/journal.pone.0275162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 09/12/2022] [Indexed: 11/06/2022] Open
Abstract
The successful occupation of the eastern Eurasian Steppe in the Late Pleistocene improved cultural connections between western Eurasia and East Asia. We document multiple waves of lithic technological transmission between the eastern Eurasian Steppe and northern China during 50-11 cal. ka BP. These waves are apparent in the sequential appearance of three techno-complexes in northern China: (1) the Mousterian techno-complex, (2) the blade techno-complex mixed with Mousterian elements, (3) and the microlithized blade techno-complex. These lithic techno-complexes were transmitted under different paleoenvironmental conditions along different pathways through the eastern Eurasian Steppe. The Mousterian techno-complex and the blade techno-complex mixed with Mousterian elements were only dispersed in the north and west peripheries of northern China (50-33 cal. ka BP). We argue that these techno-complexes failed to penetrate into the hinterland of northern China because they were not well suited to local geographical conditions. In contrast, the microlithized blade technology which diffused from the eastern Eurasian Steppe was locally modified into a Microblade techno-complex which was highly suited to local environmental conditions, and proliferated across the hinterland of northern China (28/27-11 cal. ka BP). The subsequent spread of microblade technology over vast regions of Mongolia and Siberia indicates that the Pleistocene inhabitants of northern China not only adopted and modified technologies from their neighbors in the Eurasian Steppe, but these modified variants were subsequently transmitted back into the Eurasian Steppe. These episodes of technological transmission indicate complicated patterns of population dispersal and technological interaction across northern China and the eastern Eurasian Steppe.
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Affiliation(s)
- Chao Zhao
- School of History and Civilization, Shaanxi Normal University, Xi’an, China
- * E-mail:
| | - Youping Wang
- School of Archaeology and Museology, Peking University, Beijing, China
| | - John P. Walden
- Department of Anthropology, Harvard University, Boston, Massachusetts, United States of America
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19
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Edwards GH, Blackburn T, Piccione G, Tulaczyk S, Miller GH, Sikes C. Terrestrial evidence for ocean forcing of Heinrich events and subglacial hydrologic connectivity of the Laurentide Ice Sheet. SCIENCE ADVANCES 2022; 8:eabp9329. [PMID: 36260662 PMCID: PMC9581489 DOI: 10.1126/sciadv.abp9329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 08/31/2022] [Indexed: 06/16/2023]
Abstract
During the last glacial period, the Laurentide Ice Sheet (LIS) underwent episodes of rapid iceberg discharge, recorded in ocean sediments as "Heinrich events" (HEs). Two competing models attempt to describe the stimulus for HEs via either internal ice sheet oscillations or external ocean-climate system forcing. We present a terrestrial record of HEs from the northeastern LIS that strongly supports ocean-climate forcing. Subglacial carbonate precipitates from Baffin Island record episodes of subglacial melting coincident with the three most recent HEs, resulting from acceleration of nearby marine-terminating ice streams. Synchronized ice stream acceleration over Baffin Island and Hudson Strait is inconsistent with internal ice sheet oscillations alone and indicates a shared ocean-climate stimulus to coordinate these different glaciological systems. Isotopic compositions of these precipitates record widespread subglacial groundwater connectivity beneath the LIS. Extensive basal melting and flushing of these aquifers during the last HE may have been a harbinger for terminal deglaciation.
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Affiliation(s)
- Graham H. Edwards
- Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, USA
| | - Terrence Blackburn
- Department of Earth and Planetary Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Gavin Piccione
- Department of Earth and Planetary Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Slawek Tulaczyk
- Department of Earth and Planetary Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Gifford H. Miller
- Institute of Arctic and Alpine Research and the Department of Geological Sciences, University of Colorado, Boulder, CO 80309, USA
| | - Cosmo Sikes
- Department of Geology, University of Maryland, College Park, MD 20742, USA
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20
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After the blades: The late MIS3 flake-based technology at Shuidonggou Locality 2, North China. PLoS One 2022; 17:e0274777. [PMID: 36223341 PMCID: PMC9555678 DOI: 10.1371/journal.pone.0274777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 09/05/2022] [Indexed: 11/07/2022] Open
Abstract
Contrasting with the predominance of blade-based assemblages in the Eurasian Upper Paleolithic, the large-scale persistence of a core-and-flake technology remains one of the defining features of Late Pleistocene lithic technology in East Asia. In North China, Shuidonggou is an exceptional site where both technologies are documented, therefore, it is an important archaeological sequence to understand regional technological evolution during the Marine Isotopic Stage 3. Blade technology first occurred at Shuidonggou Locality 1 and 2 around 41 ka cal BP while core-and-flake assemblages were widespread in North China. However, systematic technological studies on assemblages postdating 34 ka cal BP have not been conducted to examine whether the blade technology appeared and disappeared over a short yet abrupt episode, or persists and integrates into other forms in the region. Here, we conducted qualitative and quantitative analyses to reconstruct lithic productions on the assemblages at Shuidonggou Locality 2, dated after 34 ka cal BP. Our results show that there is a total absence of laminar elements in stone artifacts dated to 34–28 ka cal BP at Shuidonggou. Instead, we observe a dominance of an expedient production of flakes in the younger assemblages, illustrating a rapid return to flake-based technology after a relatively brief episode of stone blade production. Combining archaeological, environmental, and genetic evidence, we suggest that this technological ‘reversal’ from blades back to core and flake technology reflect population dynamics and adaptive strategies at an ecological interface between East Asian winter and summer monsoon.
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21
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Decoupled Asian monsoon intensity and precipitation during glacial-interglacial transitions on the Chinese Loess Plateau. Nat Commun 2022; 13:5397. [PMID: 36104341 PMCID: PMC9474459 DOI: 10.1038/s41467-022-33105-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/30/2022] [Indexed: 11/08/2022] Open
Abstract
AbstractThe discrepancies among the variations in global ice volume, cave stalagmite δ18O and rainfall reconstructed by cosmogenic 10Be tremendously restrain our understanding of the evolution of the East Asian summer monsoon (EASM). Here, we present a 430-ka EASM mean annual precipitation record on the Chinese Loess Plateau obtained using branched glycerol dialkyl glycerol tetraethers based on a deep learning neural network; this rainfall record corresponds well with cave-derived δ18O data from southern China but differs from precipitation reconstructed by 10Be. Both branched tetraether membrane lipids and cave δ18O may be affected by soil moisture and atmospheric temperature when glacial and interglacial conditions alternated and were thus decoupled from atmospheric precipitation; instead, they represent variations in the intensity of the EASM. Furthermore, we demonstrate that the brGDGT-DLNN method can significantly extend the temporal scale record of the EASM and is not restricted by geographic location compared with stalagmite records.
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22
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Evidence for massive methane hydrate destabilization during the penultimate interglacial warming. Proc Natl Acad Sci U S A 2022; 119:e2201871119. [PMID: 35994649 PMCID: PMC9436375 DOI: 10.1073/pnas.2201871119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Our results identify an exceptionally large warming of the equatorial Atlantic intermediate waters and strong evidence of methane release and oxidation almost certainly due to massive methane hydrate destabilization during the early part of the penultimate warm episode (126,000 to 125,000 y ago). This major warming was caused by reduced advection of cold water from high latitudes and enhanced downward heat diffusion in response to a brief episode of meltwater-induced weakening of the Atlantic meridional overturning circulation and amplified by a warm mean climate. Our results highlight climatic feedback processes associated with the penultimate climate warming that can serve as a paleoanalog for modern ongoing warming. The stability of widespread methane hydrates in shallow subsurface sediments of the marine continental margins is sensitive to temperature increases experienced by upper intermediate waters. Destabilization of methane hydrates and ensuing release of methane would produce climatic feedbacks amplifying and accelerating global warming. Hence, improved assessment of ongoing intermediate water warming is crucially important, especially that resulting from a weakening of Atlantic meridional overturning circulation (AMOC). Our study provides an independent paleoclimatic perspective by reconstructing the thermal structure and imprint of methane oxidation throughout a water column of 1,300 m. We studied a sediment sequence from the eastern equatorial Atlantic (Gulf of Guinea), a region containing abundant shallow subsurface methane hydrates. We focused on the early part of the penultimate interglacial and present a hitherto undocumented and remarkably large intermediate water warming of 6.8 °C in response to a brief episode of meltwater-induced, modest AMOC weakening centered at 126,000 to 125,000 y ago. The warming of intermediate waters to 14 °C significantly exceeds the stability field of methane hydrates. In conjunction with this warming, our study reveals an anomalously low δ13C spike throughout the entire water column, recorded as primary signatures in single and pooled shells of multitaxa foraminifers. This extremely negative δ13C excursion was almost certainly the result of massive destabilization of methane hydrates. This study documents and connects a sequence of climatic events and climatic feedback processes associated with and triggered by the penultimate climate warming that can serve as a paleoanalog for modern ongoing warming.
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23
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Cristea G, Voica C, Feher I, Puscas R, Magdas DA. Isotopic and elemental characterization of Romanian pork meat in corroboration with advanced chemometric methods: A first exploratory study. Meat Sci 2022; 189:108825. [PMID: 35461107 DOI: 10.1016/j.meatsci.2022.108825] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 04/03/2022] [Accepted: 04/06/2022] [Indexed: 11/23/2022]
Abstract
In this study 93 pork meat samples (tenderloin) were analyzed via isotope ratios mass spectrometry (δ2H, δ18O, δ13C) and inductively coupled plasma - Mass spectrometry (55 elements). The meat samples are coming from Romania and abroad. Those from Romania are originating from conventional farms and yard rearing system. The analytical results in conjunction with linear discriminant analysis (LDA) and artificial neural networks (ANNs) were used to assess: The geographical origin, and animal diet. The most powerful markers which could differentiate pork meat samples concerning the geographical origin were δ18O, terbium, and tin. The results of chemometric models showed that, along with 13C signature, rubidium concentration, and a few rare earth-elements (lanthanum, and cerium) were efficient to discriminate animal diet in a percent of 97.8% (initial classification) and 94.6% (cross-validation), respectively. Some of predictors for feeding regime differentiation by using LDA were identified also to be the best markers to distinguish corn-based diet by using ANNs (δ13C, Rb, La).
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Affiliation(s)
- Gabriela Cristea
- National Institute for Research, Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
| | - Cezara Voica
- National Institute for Research, Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania.
| | - Ioana Feher
- National Institute for Research, Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania.
| | - Romulus Puscas
- National Institute for Research, Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
| | - Dana Alina Magdas
- National Institute for Research, Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
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24
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The timing, duration and magnitude of the 8.2 ka event in global speleothem records. Sci Rep 2022; 12:10542. [PMID: 35732793 PMCID: PMC9217811 DOI: 10.1038/s41598-022-14684-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/06/2022] [Indexed: 11/09/2022] Open
Abstract
Abrupt events are a feature of many palaeoclimate records during the Holocene. The best example is the 8.2 ka event, which was triggered by a release of meltwater into the Labrador Sea and resulted in a weakening of poleward heat transport in the North Atlantic. We use an objective method to identify rapid climate events in globally distributed speleothem oxygen isotope records during the Holocene. We show that the 8.2 ka event can be identified in >70% of the speleothem records and is the most coherent signal of abrupt climate change during the last 12,000 years. The isotopic changes during the event are regionally homogenous: positive oxygen isotope anomalies are observed across Asia and negative anomalies are seen across Europe, the Mediterranean, South America and southern Africa. The magnitude of the isotopic excursions in Europe and Asia are statistically indistinguishable. There is no significant difference in the duration and timing of the 8.2 ka event between regions, or between the speleothem records and Greenland ice core records. Our study supports a rapid and global climate response to the 8.2 ka freshwater pulse into the North Atlantic, likely transmitted globally via atmospheric teleconnections.
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25
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Southern hemisphere forced millennial scale Indian summer monsoon variability during the late Pleistocene. Sci Rep 2022; 12:10136. [PMID: 35710914 PMCID: PMC9203564 DOI: 10.1038/s41598-022-14010-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 05/31/2022] [Indexed: 11/22/2022] Open
Abstract
Peninsular India hosts the initial rain-down of the Indian Summer Monsoon (ISM) after which winds travel further east inwards into Asia. Stalagmite oxygen isotope composition from this region, such as those from Belum Cave, preserve the vital signals of the past ISM variability. These archives experience a single wet season with a single dominant moisture source annually. Here we present high-resolution δ18O, δ13C and trace element (Mg/Ca, Sr/Ca, Ba/Ca, Mn/Ca) time series from a Belum Cave stalagmite spanning glacial MIS-6 (from ~ 183 to ~ 175 kyr) and interglacial substages MIS-5c-5a (~ 104 kyr to ~ 82 kyr). With most paleomonsoon reconstructions reporting coherent evolution of northern hemisphere summer insolation and ISM variability on orbital timescale, we focus on understanding the mechanisms behind millennial scale variability. Finding that the two are decoupled over millennial timescales, we address the role of the Southern Hemisphere processes in modulating monsoon strength as a part of the Hadley circulation. We identify several strong and weak episodes of ISM intensity during 104–82 kyr. Some of the weak episodes correspond to warming in the southern hemisphere associated with weak cross-equatorial winds. We show that during the MIS-5 substages, ISM strength gradually declined with millennial scale variability linked to Southern Hemisphere temperature changes which in turn modulate the strength of the Mascarene High.
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26
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Records of Organic Carbon Isotopic Composition and Its Paleoenvironmental Implications in Shengshan Island Loess Deposition in the East China Sea during the Last Glacial Period. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12115724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Organic carbon isotopic composition (δ13Corg) in loess deposits is an important indicator of terrestrial paleovegetation, and it has been widely used for paleoenvironmental reconstruction in aeolian sediments around the world. However, little research has been done on the variation and paleoenvironmental implication of δ13Corg from loess deposits on Shengshan Island, East China Sea, during the last glacial period (LG). In this research, we present optically stimulated luminescence (OSL) ages, total organic carbon (TOC) data and δ13Corg records of the loess section at Chenqianshan (CQS) on Shengshan Island. Additionally, to study the effectiveness of δ13Corg in documenting paleoenvironmental changes, magnetic susceptibilities and diffuse reflectance spectra were surveyed. TOC concentration for the CQS loess section ranged from 0.11% to 0.47%, and the δ13Corg composition of the CQS loess section varied between −20.80‰ and −24.56‰ during the LG. The average value of C4 abundance was 21.31%. TOC, δ13Corg, χfd, and Hm/(Hm + Gt) curves for the CQS loess section showed similar patterns. The results of our study indicated that the vegetation of the CQS loess deposit was mainly C3/C4 mixed vegetation, and C3 vegetation was the most important vegetation. The comparison between the δ13Corg curve for the CQS section and other existing δ13Corg records of the loess sections from central and northern China showed similar trends and their vegetation succession exhibited synchronous change during the LG. Based on a comparison of the δ13Corg record, C4 abundance and χfd of the CQS section and other global geological records, it was concluded that the mutual effects of precipitation and temperature caused the change of paleovegetation in loess deposits on islands in the East China Sea during the LG.
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27
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Álvarez-Fernández E, Aura Tortosa JE, Jordá Pardo JF, Palomero-Jiménez I, Aparicio MT, Cabello-Ligero L, Cantalejo P, Vadillo Conesa M, Marco YC, Espejo MDM, Fernández-Gómez MJ, García-Ibaibarriaga N, Maestro A, Marlasca R, Martín-Vallejo FJ, Murelaga X, Pérez-Ripoll M. Maritime-oriented foragers during the Late Pleistocene on the eastern costa del sol (Southeast Iberia): Cueva Victoria (Málaga, Spain). Heliyon 2022; 8:e09548. [PMID: 35669540 PMCID: PMC9163520 DOI: 10.1016/j.heliyon.2022.e09548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/11/2021] [Accepted: 05/20/2022] [Indexed: 11/30/2022] Open
Abstract
The Mediterranean coast of Spain is marked by several clusters of Palaeolithic sites: to the south of the Pyrenees, in the area around the Ebro River, in the central part, and on the south coast, one of the southernmost regions in Europe. The number of sites is small compared with northern Iberia, but like that region, the Palaeolithic occupations are accompanied by several rock art ensembles. The archaeological material (both biotic and abiotic resources) and radiocarbon dates presented here were obtained during archaeological fieldwork of professor J. Fortea in the Late Pleistocene deposits in Cueva Victoria, located near the modern coastline and about 150 km north of the Strait of Gibraltar. In the three occupation phases, marine resources were acquired by shell-fishing (focusing almost exclusively on the clam Ruditapes decussatus), fishing, and the use of beached marine mammals. This contrasts with the limited data about the exploitation of terrestrial resources by hunting and gathering animals and plants. The study is completed by the study of artefacts (lithic and bone industry and objects of adornment) that help to understand the subsistence strategies of the cave occupants and enable a comparison with other groups inhabiting the Mediterranean coasts of the Iberian Peninsula during Greenland Interstadial 1, between ca. 15.1 and 13.6 cal BP.
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Affiliation(s)
- Esteban Álvarez-Fernández
- Departamento de Prehistoria, Historia Antigua y Arqueología, Universidad de Salamanca, Calle Cerrada de Serranos s/n, 37002, Salamanca, Spain.,Grupo de Investigador Reconocido PREHUSAL, Universidad de Salamanca, Spain
| | - J Emili Aura Tortosa
- Departament de Prehistòria Arqueologia i Història Antiga-PREMEDOC, Universitat de València, Avda. Blasco Ibañez 28, E-46010, València, Spain
| | - Jesús F Jordá Pardo
- Laboratorio de Estudios Paleolíticos, Departamento de Prehistoria y Arqueología, Facultad de Geografía e Historia, Universidad Nacional de Educación a Distancia, Paseo Senda del Rey 7, 28040, Madrid, Spain.,Grupo de Investigador Reconocido PREHUSAL, Universidad de Salamanca, Spain
| | - Ismael Palomero-Jiménez
- Departamento de Prehistoria, Historia Antigua y Arqueología, Universidad de Salamanca, Calle Cerrada de Serranos s/n, 37002, Salamanca, Spain
| | - Mª Teresa Aparicio
- Museo Nacional de Ciencias Naturales, CSIC, C. José Gutiérrez Abascal, 2, 28006, Madrid, Spain
| | | | - Pedro Cantalejo
- Museo Municipal de la Historia y las Tradiciones de Ardales, Cueva de Ardales, Ayuntamiento de Ardales, Avda. de Málaga, 1, 29550, Ardales, Málaga, Spain
| | - Margarita Vadillo Conesa
- Departament de Prehistòria Arqueologia i Història Antiga-PREMEDOC, Universitat de València, Avda. Blasco Ibañez 28, E-46010, València, Spain
| | - Yolanda Carrión Marco
- Departament de Prehistòria Arqueologia i Història Antiga-PREMEDOC, Universitat de València, Avda. Blasco Ibañez 28, E-46010, València, Spain
| | - María Del Mar Espejo
- Museo Municipal de la Historia y las Tradiciones de Ardales, Cueva de Ardales, Ayuntamiento de Ardales, Avda. de Málaga, 1, 29550, Ardales, Málaga, Spain
| | - Mª José Fernández-Gómez
- Departamento de Estadística, Facultad de Medicina, Universidad de Salamanca, Campus Miguel de Unamuno, 37007, Salamanca, Spain.,Grupo de Investigador Reconocido PREHUSAL, Universidad de Salamanca, Spain
| | - Naroa García-Ibaibarriaga
- Departamento de Geografía, Prehistoria y Arqueología, Facultad de Letras, Universidad del País Vasco UPV/EHU, C. Tomás y Valiente s/n, 01006, Vitoria-Gasteiz, Spain
| | - Adolfo Maestro
- Department of Geoscientific Research and Prospective, IGME, Calle Calera 1., E-28760, Tres Cantos, Madrid, Spain
| | | | - F Javier Martín-Vallejo
- Departamento de Estadística, Facultad de Medicina, Universidad de Salamanca, Campus Miguel de Unamuno, 37007, Salamanca, Spain.,Grupo de Investigador Reconocido PREHUSAL, Universidad de Salamanca, Spain
| | - Xavier Murelaga
- Departamento de Geología, Facultad de Ciencia y Tecnología, Departamento de Estratigrafía y Paleontología, Universidad del País Vasco UPV/EHU, Apartado 644, 48080, Bilbao, Spain
| | - Manuel Pérez-Ripoll
- Departament de Prehistòria Arqueologia i Història Antiga-PREMEDOC, Universitat de València, Avda. Blasco Ibañez 28, E-46010, València, Spain
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28
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Zhang P, Zhang X, Zhang X, Gao X, Huerta-Sanchez E, Zwyns N. Denisovans and Homo sapiens on the Tibetan Plateau: dispersals and adaptations. Trends Ecol Evol 2022; 37:257-267. [PMID: 34863581 PMCID: PMC9140327 DOI: 10.1016/j.tree.2021.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/31/2021] [Accepted: 11/01/2021] [Indexed: 10/19/2022]
Abstract
Recent archaeological discoveries suggest that both archaic Denisovans and Homo sapiens occupied the Tibetan Plateau earlier than expected. Genetic studies show that a pulse of Denisovan introgression was involved in the adaptation of Tibetan populations to high-altitude hypoxia. These findings challenge the traditional view that the plateau was one of the last places on earth colonized by H. sapiens and warrant a reappraisal of the population history of this highland. Here, we integrate archaeological and genomic evidence relevant to human dispersal, settlement, and adaptation in the region. We propose two testable models to address the peopling of the plateau in the broader context of H. sapiens dispersal and their encounters with Denisovans in Asia.
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Affiliation(s)
- Peiqi Zhang
- Department of Anthropology, University of California, Davis, CA 95616, USA.
| | - Xinjun Zhang
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA
| | - Xiaoling Zhang
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China; CAS Center for Excellence in Life and Paleoenvironment, Beijing 10044, China
| | - Xing Gao
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China; CAS Center for Excellence in Life and Paleoenvironment, Beijing 10044, China
| | - Emilia Huerta-Sanchez
- Department of Ecology and Evolutionary Biology and Center for Computational Molecular Biology, Brown University, Providence, RI 02912, USA
| | - Nicolas Zwyns
- Department of Anthropology, University of California, Davis, CA 95616, USA; Department of Human Evolution, Max Planck Insititute for Evolutionary Anthropology, Leipzig 04103, Germany
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29
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Domínguez-Villar D, Krklec K, Boomer I, Fairchild IJ. ISODRIP, a model to transfer the δ 18O signal of precipitation to drip water - Implementation of the model for Eagle Cave (central Spain). THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 797:149188. [PMID: 34346358 DOI: 10.1016/j.scitotenv.2021.149188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 07/13/2021] [Accepted: 07/17/2021] [Indexed: 06/13/2023]
Abstract
The isotope signature of cave waters provides an excellent opportunity to better understand the recharge in karst regions and the complexity of drainage systems in the vadose zone. We have developed a cave isotope hydrological model (ISODRIP) that requires entering basic hydrometeorological information and a precipitation δ18O record to simulate the discharge and δ18O signals of different drip sites. The model includes four different modules to simulate various flow route regimes: continuous and discontinuous drips under diffuse or preferential flows. We use precipitation and cave water δ18O records that were obtained in Eagle Cave (central Spain) during a 5-year period to test our model and to better understand the dynamics of karst aquifers. Eagle Cave waters do not record evaporation. The δ18O signals do not have seasonality, although they record intra-annual and inter-annual variability. Additionally, cave water δ18O signal falls within the range of the annual average weighted isotope composition of precipitation. Well-mixed cave waters, that characterize diffuse flows, record 1‰ δ18O variability, whereas partially-mixed waters, that flow along preferential drainage routes, have up to 3‰ δ18O variability. The results suggest that precipitation takes on average 15 months to reach the cave through the diffuse flow network, whereas under preferential flow the transit time is highly variable depending on the previous condition of the system. ISODRIP includes a soil layer above the vadose zone that controls large recharge events, together with direct recharge components that bypass the soil layer enabling at least some recharge all year round. Thus, the simulations reproduce the observed lack of seasonal bias in the cave water δ18O composition in relation to the average weighted isotope composition of precipitation. This research highlights the importance of understanding recharge dynamics and the configuration of particular drips sites to properly interpret speleothem δ18O records.
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Affiliation(s)
- David Domínguez-Villar
- Department of Soil Science, Faculty of Agriculture, University of Zagreb, Svetošimunska 25, 10000 Zagreb, Croatia.
| | - Kristina Krklec
- Department of Soil Science, Faculty of Agriculture, University of Zagreb, Svetošimunska 25, 10000 Zagreb, Croatia
| | - Ian Boomer
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Ian J Fairchild
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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30
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Mid-Late Holocene Stalagmite δ18O and δ13C Records in Naduo Cave, Guizhou Province, China. J CHEM-NY 2021. [DOI: 10.1155/2021/7624833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Global warming and climate anomalies have attracted worldwide attention. The study of global climate change has received increasing attention from all countries and fields worldwide. Paleoclimate research is an important way to understand past global change and environmental evolution and to simulate and predict future climate development. A stalagmite ND3 collected in Naduo Cave was used to reconstruct the history of local climate and environmental changes from 0.55 to 5.07 ka BP based on the data of 13 230Th ages and 642 groups of oxygen and carbon stable isotopes. First, according to correlation analysis, δ18O and δ13C were significantly correlated (correlation coefficient r = 0.308, n = 318,
) during the 5.07–2.00 ka BP period. However, during the period of 2–0.55 ka BP, there was no significant correlation
. The δ18O and δ13C data indicate that the climatic environment changed asynchronously during the period of 2.00–0.55 ka BP. During the period of 5.07–2.00 ka BP, the influence of human activities was weak, and δ18O and δ13C indicate similar climatic and environmental conditions, both of which changed in the same direction (positive correlation). In other words, when δ18O was positive, it indicated weak summer monsoons and lower precipitation, which led to declines in vegetation, weakened biological activity, and decreased soil CO2 and positive δ13C. The reverse patterns were also true. Since 2.0 ka BP, the intensity of human activities and the transformation and influence of surface vegetation have increased, and native vegetation has been destroyed in large quantities. Therefore, the climatic and environmental significance indicated by δ13C and δ18O has been well demonstrated. Second, the δ18O records showed that stalagmite ND3 responded to the weak monsoon drought events of 4.2 ka BP and 2.8 ka BP in the Holocene in a discontinuous deposition manner, which brings up new directions for future research.
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31
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Asami R, Hondo R, Uemura R, Fujita M, Yamasaki S, Shen CC, Wu CC, Jiang X, Takayanagi H, Shinjo R, Kano A, Iryu Y. Last glacial temperature reconstructions using coupled isotopic analyses of fossil snails and stalagmites from archaeological caves in Okinawa, Japan. Sci Rep 2021; 11:21922. [PMID: 34754040 PMCID: PMC8578419 DOI: 10.1038/s41598-021-01484-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 10/28/2021] [Indexed: 11/09/2022] Open
Abstract
We applied a new geoarchaeological method with two carbonate archives, which are fossil snails from Sakitari Cave and stalagmites from Gyokusen Cave, on Okinawa Island, Japan, to reconstruct surface air temperature changes over the northwestern Pacific since the last glacial period. Oxygen isotope ratios (δ18O) of modern and fossil freshwater snail shells were determined to infer seasonal temperature variations. The observational and analytical data confirm that δ18O values of fluid inclusion waters in the stalagmite can be regarded as those of spring waters at the sites where snails lived. Our results indicate that the annual mean, summer, and winter air temperatures were lower by 6–7 °C at ca. 23 thousand years ago (ka) and 4–5 °C at ca. 16–13 ka than those of the present day. Our reconstruction implies that surface air cooling was possibly two times greater than that of seawater around the Ryukyu Islands during the Last Glacial Maximum, which potentially enhanced the development of the East Asian summer monsoon during the last deglaciation. Considering the potential uncertainties in the temperature estimations, the climatic interpretations of this study are not necessarily definitive due to the limited number of samples. Nevertheless, our new geoarchaeological approach using coupled δ18O determinations of fossil snails and stalagmite fluid inclusion waters will be useful for reconstructing snapshots of seasonally resolved time series of air temperatures during the Quaternary.
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Affiliation(s)
- Ryuji Asami
- Institute of Geology and Paleontology, Graduate School of Science, Tohoku University, Aobayama, Sendai, 980-8578, Japan.
| | - Rikuto Hondo
- Institute of Geology and Paleontology, Graduate School of Science, Tohoku University, Aobayama, Sendai, 980-8578, Japan
| | - Ryu Uemura
- Department of Earth and Environmental Sciences, Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Masaki Fujita
- Department of Anthropology, National Museum of Nature and Science, Tsukuba, Ibaraki, 305-0005, Japan
| | - Shinji Yamasaki
- Okinawa Prefectural Museum & Art Museum, Okinawa, 900-0006, Japan
| | - Chuan-Chou Shen
- High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC), Department of Geosciences, National Taiwan University, Taipei, 10617, Taiwan, ROC.,Research Center for Future Earth, National Taiwan University, Taipei, 10617, Taiwan, ROC
| | - Chung-Che Wu
- High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC), Department of Geosciences, National Taiwan University, Taipei, 10617, Taiwan, ROC.,Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093, Zurich, Switzerland
| | - Xiuyang Jiang
- Key Laboratory of Humid Subtropical Eco-Geographical Processes, College of Geography Science, Ministry of Education, Fujian Normal University, Fuzhou, 350007, China
| | - Hideko Takayanagi
- Institute of Geology and Paleontology, Graduate School of Science, Tohoku University, Aobayama, Sendai, 980-8578, Japan
| | - Ryuichi Shinjo
- Research Institute for Humanity and Nature (RIHN), Motoyama 457-4, Kamigamo, Kita-ku, Kyoto, 603-8047, Japan.,Department of Earth Science, Faculty of Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 903-0213, Japan
| | - Akihiro Kano
- Department of Earth and Planetary Science, Faculty of Science, The University of Tokyo, 7-3-1 Hongo, Tokyo, 113-0033, Japan
| | - Yasufumi Iryu
- Institute of Geology and Paleontology, Graduate School of Science, Tohoku University, Aobayama, Sendai, 980-8578, Japan
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32
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Bagniewski W, Ghil M, Rousseau DD. Automatic detection of abrupt transitions in paleoclimate records. CHAOS (WOODBURY, N.Y.) 2021; 31:113129. [PMID: 34881579 DOI: 10.1063/5.0062543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
Bifurcations and tipping points (TPs) are an important part of the Earth system's behavior. These critical points represent thresholds at which small changes in the system's parameters or in the forcing abruptly switch it from one state or type of behavior to another. Current concern with TPs is largely due to the potential of slow anthropogenic forcing to bring about abrupt, and possibly irreversible, change to the physical climate system and impacted ecosystems. Paleoclimate proxy records have been shown to contain abrupt transitions, or "jumps," which may represent former instances of such dramatic climate change events. These transitions can provide valuable information for identifying critical TPs in current and future climate evolution. Here, we present a robust methodology for detecting abrupt transitions in proxy records that is applied to ice core and speleothem records of the last climate cycle. This methodology is based on the nonparametric Kolmogorov-Smirnov (KS) test for the equality, or not, of the probability distributions associated with two samples drawn from a time series, before and after any potential jump. To improve the detection of abrupt transitions in proxy records, the KS test is augmented by several other criteria and it is compared with recurrence analysis. The augmented KS test results show substantial skill when compared with more subjective criteria for jump detection. This test can also usefully complement recurrence analysis and improve upon certain aspects of its results.
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Affiliation(s)
- W Bagniewski
- Department of Geosciences and Laboratoire de Météorologie Dynamique (CNRS and IPSL), École Normale Supérieure and PSL University, 75132 Paris Cedex 05, France
| | - M Ghil
- Department of Geosciences and Laboratoire de Météorologie Dynamique (CNRS and IPSL), École Normale Supérieure and PSL University, 75132 Paris Cedex 05, France
| | - D D Rousseau
- Geosciences Montpellier, University of Montpellier, CNRS, 34095 Montpellier, France
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Deglacial variability of South China hydroclimate heavily contributed by autumn rainfall. Nat Commun 2021; 12:5875. [PMID: 34620854 PMCID: PMC8497617 DOI: 10.1038/s41467-021-26106-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 09/17/2021] [Indexed: 02/08/2023] Open
Abstract
The deglacial hydroclimate in South China remains a long-standing topic of debate due to the lack of reliable moisture proxies and inconsistent model simulations. A recent hydroclimate proxy suggests that South China became wet in cold stadials during the last deglaciation, with the intensification proposed to be contributed mostly by the East Asian summer monsoon (EASM). Here, based on a deglacial simulation in a state-of-the-art climate model that well reproduces the evolution of EASM, winter monsoon (EAWM) and the associated water isotopes in East Asia, we propose that the intensified hydroclimate in South China is also contributed heavily by the rainfall in autumn, during the transition between EASM and EAWM. The excessive rainfall in autumn results from the convergence between anomalous northerly wind due to amplified land-sea thermal contrast and anomalous southerly wind associated with the anticyclone over Western North Pacific, both of which are, in turn, forced by the slowdown of the Atlantic thermohaline circulation. Regardless the rainfall change, however, the modeled δ18Op remains largely unchanged in autumn. Our results provide new insights to East Asia monsoon associated with climate change in the North Atlantic.
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Wang F, Guo Y, Xian Q, Li M, Rui X, Xie F. Luminescence chronology for the Paleolithic site of Xinmiaozhuang Locality 1 (XMZ1) in the Nihewan Basin, northern China, and its paleoenvironmental and archaeological implications. J Hum Evol 2021; 157:103033. [PMID: 34246050 DOI: 10.1016/j.jhevol.2021.103033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 06/02/2021] [Accepted: 06/02/2021] [Indexed: 10/20/2022]
Abstract
In contrast to the prevailing view that the Chinese Paleolithic has been dominated by the Mode 1 technology-with a slow and conservative development from the Early to the Late Pleistocene-recent discoveries indicate that the lithic technology might have developed into an 'advanced' phase in some parts of China, at least since the early Late Pleistocene. The Xinmiaozhuang Locality 1 (XMZ1), located on the southern edge of the Nihewan Basin in northern China, is one of the examples belonging to such an 'advanced' phase. Although the stone artifacts at this site still belong to the long-existing 'small-tool' industry (core-and-flake) in this basin, some 'advanced' traits, including discoidal cores, elongated flakes, and 'Mousterian-like' triangular points and scrapers, are present. We provide a dating of the XMZ1 using the multiple elevated temperatures (MET) post infrared (pIR) infrared stimulated luminescence (IRSL) procedure (MET-pIRIR) on both multigrained single aliquots and 'individual' grains of potassium-rich feldspars (K-feldspars). The consistency between the single-aliquot and single-grain K-feldspar equivalent dose results mutually confirmed the reliability of the obtained ages. Our chronology indicates that the cultural layer falls within the period of ca. 63-75 ka, corresponding to the early stage of the Marine Isotope Stage (MIS) 4. Based on the correlation of the cultural age to the environmental proxies of loess and stalagmites from China, we suggest that the site might have witnessed dramatic fluctuations of paleoclimate during the site formation. Additionally, based on the discoidal cores distribution, a potential corridor along the Xuefeng-Wu-Tainhang-Great Khingan Mountains for ancient humans migrating between South and North China is suggested. However, more archaeological and chronological studies are required to figure out the origin and the dispersal patterns of the discoidal core associated with lithic assemblage and the tool-makers in East Asia.
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Affiliation(s)
- Fagang Wang
- Hebei Provincial Institute of Cultural Relics and Archaeology, Shijiazhuang, 050031, China
| | - Yujie Guo
- Institute of Nihewan Archaeology, College of History and Culture, Hebei Normal University, Shijiazhuang, 050024, China.
| | - Qi Xian
- Institute of Nihewan Archaeology, College of History and Culture, Hebei Normal University, Shijiazhuang, 050024, China
| | - Manyue Li
- Institute of Nihewan Archaeology, College of History and Culture, Hebei Normal University, Shijiazhuang, 050024, China
| | - Xue Rui
- College of Earth Sciences, Jilin University, Changchun 130061, China
| | - Fei Xie
- Hebei Provincial Institute of Cultural Relics and Archaeology, Shijiazhuang, 050031, China
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35
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He C, Liu Z, Otto-Bliesner BL, Brady EC, Zhu C, Tomas R, Buizert C, Severinghaus JP. Abrupt Heinrich Stadial 1 cooling missing in Greenland oxygen isotopes. SCIENCE ADVANCES 2021; 7:7/25/eabh1007. [PMID: 34134984 PMCID: PMC8208719 DOI: 10.1126/sciadv.abh1007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/29/2021] [Indexed: 05/10/2023]
Abstract
Abrupt climate changes during the last deglaciation have been well preserved in proxy records across the globe. However, one long-standing puzzle is the apparent absence of the onset of the Heinrich Stadial 1 (HS1) cold event around 18 ka in Greenland ice core oxygen isotope δ18 O records, inconsistent with other proxies. Here, combining proxy records with an isotope-enabled transient deglacial simulation, we propose that a substantial HS1 cooling onset did indeed occur over the Arctic in winter. However, this cooling signal in the depleted oxygen isotopic composition is completely compensated by the enrichment because of the loss of winter precipitation in response to sea ice expansion associated with AMOC slowdown during extreme glacial climate. In contrast, the Arctic summer warmed during HS1 and YD because of increased insolation and greenhouse gases, consistent with snowline reconstructions. Our work suggests that Greenland δ18 O may substantially underestimate temperature variability during cold glacial conditions.
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Affiliation(s)
- Chengfei He
- College of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing, China
- Department of Geography, The Ohio State University, Columbus, OH 43210, USA
- Open Studio for Ocean-Climate-Isotope Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Zhengyu Liu
- Department of Geography, The Ohio State University, Columbus, OH 43210, USA.
- College of Geography Sciences, Nanjing Normal University, Nanjing, China
| | - Bette L Otto-Bliesner
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO 80305, USA
| | - Esther C Brady
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO 80305, USA
| | - Chenyu Zhu
- Open Studio for Ocean-Climate-Isotope Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
- Key Laboratory of Physical Oceanography, Ocean University of China, Qingdao, China
| | - Robert Tomas
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO 80305, USA
| | - Christo Buizert
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA
| | - Jeffrey P Severinghaus
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92037, USA
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36
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Li TY, Wu Y, Shen CC, Li JY, Chiang HW, Lin K, Tan LC, Jiang XY, Cheng H, Edwards RL. High precise dating on the variation of the Asian summer monsoon since 37 ka BP. Sci Rep 2021; 11:9375. [PMID: 33931675 PMCID: PMC8087833 DOI: 10.1038/s41598-021-88597-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 04/14/2021] [Indexed: 11/09/2022] Open
Abstract
Comprehensive comparison of paleoclimate change based on records constrained by precise chronology and high-resolution is essential to explore the correlation and interaction within earth climate systems. Here, we propose a new stalagmite-based multidecadal resolved Asian summer monsoon (ASM) record spanning the past thirty-seven thousand years (ka BP, before AD 1950) from Furong Cave, southwestern China. This record is consistent with the published Chinese stalagmite sequences and shows that the dominant controls of the ASM dynamics include not only insolation and solar activity but also suborbital-scale hydroclimate events in the high latitudes of the northern hemisphere, such as the Heinrich events, Bølling-Allerød (BA), and Younger Dryas (YD). Benefit from the unprecedented accurate chronology, the timings of these events are precisely dated, with uncertainties of, at most, 40 years (2σ). The onset of the weak ASM during the YD began at 12.92 ka BP and lasted for 430 years. The occurrence of the 200-yr Older Dryas during the BA period was dated from 13.87 to 14.06 ka BP. The durations of the three Heinrich (H) events, H1, H2, and H3, are 14.33-18.29, 23.77-24.48, and 28.98-30.46 ka BP, respectively. Furong record shows surprisingly variable onset transitions of 980, 210, and 40 years for the corresponding weak ASM events. These discrepancies suggest different influences of the H events on ASM dynamics. During the periods of H 1-3, the obvious difference between our Furong record and NGRIP δ18O record indicated the decoupling correlation between the mid-low latitudes and high latitudes. On the other hand, synchronous climate change in high and low latitudes suggests another possibility which different to the dominant role of Northern high latitudes in triggering global climate change. Our high quality records also indicate a plausible different correlation between the high and mid-low latitudes under glacial and inter-glacial background, especially for the ASM regimes.
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Affiliation(s)
- Ting-Yong Li
- Yunnan Key Laboratory of Plateau Geographical Processes and Environmental Change, Faculty of Geography, Yunnan Normal University, Kunming, 650500, China.
| | - Yao Wu
- Chongqing Key Laboratory of Karst Environment, School of Geographical Sciences, Southwest University, Chongqing, 400715, China
| | - Chuan-Chou Shen
- High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC), Department of Geosciences, National Taiwan University, Taipei, 10617, Taiwan.
| | - Jun-Yun Li
- Chongqing Key Laboratory of Karst Environment, School of Geographical Sciences, Southwest University, Chongqing, 400715, China
| | - Hong-Wei Chiang
- Department of Geosciences, National Taiwan University, Taipei, 10617, Taiwan, ROC
| | - Ke Lin
- High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC), Department of Geosciences, National Taiwan University, Taipei, 10617, Taiwan.,Earth Observatory of Singapore, Nanyang Technological University, Singapore, 639798, Singapore
| | - Liang-Cheng Tan
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710075, China
| | - Xiu-Yang Jiang
- College of Geographical Science, Fujian Normal University, Fuzhou, 350007, China
| | - Hai Cheng
- Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an, 710049, China.,Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN, 55455, USA
| | - R Lawrence Edwards
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN, 55455, USA
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37
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StalGrowth—A Program to Estimate Speleothem Growth Rates and Seasonal Growth Variations. GEOSCIENCES 2021. [DOI: 10.3390/geosciences11050187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Speleothems are one of the few archives which allow us to reconstruct the terrestrial paleoclimate and help us to understand the important climate dynamics in inhabited regions of our planet. Their time of growth can be precisely dated by radiometric techniques, but unfortunately seasonal radiometric dating resolution is so far not feasible. Numerous cave environmental monitoring studies show evidence for significant seasonal variations in parameters influencing carbonate deposition (calcium-ion concentration, cave air pCO2, drip rate and temperature). Variations in speleothem deposition rates need to be known in order to correctly decipher the climate signal stored in the speleothem archive. StalGrowth is the first software to quantify growth rates based on cave monitoring results, detect growth seasonality and estimate the seasonal growth bias. It quickly plots the predicted speleothem growth rate together with the influencing cave environmental parameters to identify which parameter(s) cause changes in speleothem growth rate, and it can also identify periods of no growth. This new program has been applied to multiannual cave monitoring studies in Austria, Gibraltar, Puerto Rico and Texas, and it has identified two cases of seasonal varying speleothem growth.
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38
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Abstract
Data availability and temporal resolution make it challenging to unravel the anatomy (duration and temporal phasing) of the Last Glacial abrupt climate changes. Here, we address these limitations by investigating the anatomy of abrupt changes using sub-decadal-scale records from Greenland ice cores. We highlight the absence of a systematic pattern in the anatomy of abrupt changes as recorded in different ice parameters. This diversity in the sequence of changes seen in ice-core data is also observed in climate parameters derived from numerical simulations which exhibit self-sustained abrupt variability arising from internal atmosphere-ice-ocean interactions. Our analysis of two ice cores shows that the diversity of abrupt warming transitions represents variability inherent to the climate system and not archive-specific noise. Our results hint that during these abrupt events, it may not be possible to infer statistically-robust leads and lags between the different components of the climate system because of their tight coupling.
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39
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Risi C, Muller C, Blossey P. Rain Evaporation, Snow Melt, and Entrainment at the Heart of Water Vapor Isotopic Variations in the Tropical Troposphere, According to Large-Eddy Simulations and a Two-Column Model. JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS 2021; 13:e2020MS002381. [PMID: 33868576 PMCID: PMC8047889 DOI: 10.1029/2020ms002381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 02/08/2021] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
We aim at developing a simple model as an interpretative framework for the water vapor isotopic variations in the tropical troposphere over the ocean. We use large-eddy simulations of disorganized convection in radiative-convective equilibrium to justify the underlying assumptions of this simple model, to constrain its input parameters and to evaluate its results. We also aim at interpreting the depletion of the water vapor isotopic composition in the lower and midtroposphere as precipitation increases, which is a salient feature in tropical oceanic observations. This feature constitutes a stringent test on the relevance of our interpretative framework. Previous studies, based on observations or on models with parameterized convection, have highlighted the roles of deep convective and mesoscale downdrafts, rain evaporation, rain-vapor diffusive exchanges, and mixing processes. The interpretative framework that we develop, valid in case of disorganized convection, is a two-column model representing the net ascent in clouds and the net descent in the environment. We show that the mechanisms for depleting the troposphere as the precipitation rate increases all stem from the higher tropospheric relative humidity. First, when the relative humidity is larger, less snow sublimates before melting and a smaller fraction of rain evaporates. Both effects lead to more depleted rain evaporation and eventually more depleted water vapor. This mechanism dominates in regimes of large-scale ascent. Second, the entrainment of dry air into clouds reduces the vertical isotopic gradient and limits the depletion of tropospheric water vapor. This mechanism dominates in regimes of large-scale descent.
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Affiliation(s)
- Camille Risi
- Laboratoire de Meteorologie DynamiqueIPSLCNRSEcole Normale SuperieureSorbonne UniversitePSL Research UniversityParisFrance
| | - Caroline Muller
- Laboratoire de Meteorologie DynamiqueIPSLCNRSEcole Normale SuperieureSorbonne UniversitePSL Research UniversityParisFrance
| | - Peter Blossey
- Department of Atmospheric SciencesUniversity of WashingtonSeattleWAUSA
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40
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Peng W, Huang X, Storozum MJ, Fan Y, Zhang H. An updated chronology and paleoenvironmental background for the Paleolithic Loufangzi site, North China. J Hum Evol 2021; 152:102948. [PMID: 33529839 DOI: 10.1016/j.jhevol.2020.102948] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 12/27/2020] [Accepted: 12/27/2020] [Indexed: 10/22/2022]
Abstract
The relationship between the environment and human activities during Marine Isotope Stage (MIS) 4 is important for understanding the origins of modern humans (Homo sapiens) in East Asia, an area where various hypotheses of human origins have been vigorously debated over the past three decades. Unfortunately, only a handful of Paleolithic sites date to MIS 4 in East Asia, hampering our understanding of how environmental changes affected human activities during this time period. Here, we used stratigraphic correlation analysis and optically stimulated luminescence to date the Loufangzi site, an important Paleolithic site in North China that has had an unreliable chronology. Pollen analysis, grain size, and magnetic susceptibility were also used to reconstruct environmental conditions at the Loufangzi site area. Our results show that (1) the age of the upper culture layer of the Loufangzi site is bracketed between ∼70 ka and ∼60 ka and dates to MIS 4 and (2) the regional vegetation from MIS 5 to MIS 4 to MIS 3 was mainly dominated by forest steppe, desert steppe/desert, and steppe, respectively, indicating harsh environmental conditions during MIS 4. Combined with the discovery of Mousterian-like scrapers in the upper culture layer of MIS 4, our results challenge the view that the area was unsuitable for human survival during the Last Glacial period and instead suggest that humans used new technologies to increase their resilience to the cooling climate.
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Affiliation(s)
- Wei Peng
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming Yunnan, 650504, China; Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou Gansu, 730000, China
| | - Xiaozhong Huang
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou Gansu, 730000, China.
| | - Michael J Storozum
- Institute of Archaeological Science, Fudan University, 220 Handan Road, Yangpu District, Shanghai, 200433, China; Department of Cultural Heritage and Museology, Fudan University, 220 Handan Road, Yangpu District, Shanghai, 200433, China
| | - Yuxin Fan
- School of Earth Sciences & Key Laboratory of Mineral Resources in Western China (Gansu Province), Lanzhou University, Lanzhou 730000, China
| | - Hucai Zhang
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming Yunnan, 650504, China.
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41
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He C, Liu Z, Otto-Bliesner BL, Brady EC, Zhu C, Tomas R, Clark PU, Zhu J, Jahn A, Gu S, Zhang J, Nusbaumer J, Noone D, Cheng H, Wang Y, Yan M, Bao Y. Hydroclimate footprint of pan-Asian monsoon water isotope during the last deglaciation. SCIENCE ADVANCES 2021; 7:eabe2611. [PMID: 33523950 DOI: 10.1126/sciadv.abe2611] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/04/2020] [Indexed: 05/05/2023]
Abstract
Oxygen isotope speleothem records exhibit coherent variability over the pan-Asian summer monsoon (AM) region. The hydroclimatic representation of these oxygen isotope records for the AM, however, has remained poorly understood. Here, combining an isotope-enabled Earth system model in transient experiments with proxy records, we show that the widespread AM δ18Oc signal during the last deglaciation (20 to 11 thousand years ago) is accompanied by a continental-scale, coherent hydroclimate footprint, with spatially opposite signs in rainfall. This footprint is generated as a dynamically coherent response of the AM system primarily to meltwater forcing and secondarily to insolation forcing and is further reinforced by atmospheric teleconnection. Hence, widespread δ18Op depletion in the AM region is accompanied by a northward migration of the westerly jet and enhanced southwesterly monsoon wind, as well as increased rainfall from South Asia (India) to northern China but decreased rainfall in southeast China.
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Affiliation(s)
- C He
- College of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing, China
- Department of Geography, The Ohio State University, Columbus, OH, USA
- Open Studio for Ocean-Climate-Isotope Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Z Liu
- College of Geography Science, Nanjing Normal University, Nanjing, China.
- Department of Geography, The Ohio State University, Columbus, OH, USA
| | - B L Otto-Bliesner
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - E C Brady
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - C Zhu
- Open Studio for Ocean-Climate-Isotope Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
- Department of Geography, The Ohio State University, Columbus, OH, USA
| | - R Tomas
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - P U Clark
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
- School of Geography and Environmental Sciences, University of Ulster, Coleraine, Northern Ireland BT52 1SA, UK
| | - J Zhu
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - A Jahn
- Department for Atmospheric and Oceanic Sciences and Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA
| | - S Gu
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
- Department of Geography, The Ohio State University, Columbus, OH, USA
| | - J Zhang
- Cooperative Institute for Climate, Ocean, and Ecosystem Studies, University of Washington, Seattle, WA, USA
- NOAA/Pacific Marine Environmental Laboratory, Seattle, WA, USA
| | - J Nusbaumer
- College of Geography Science, Nanjing Normal University, Nanjing, China
| | - D Noone
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
| | - H Cheng
- Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an, China
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China
- Department of Earth Sciences, University of Minnesota, Minneapolis, MN, USA
| | - Y Wang
- College of Geography Science, Nanjing Normal University, Nanjing, China
| | - M Yan
- College of Geography Science, Nanjing Normal University, Nanjing, China
- Open Studio for Ocean-Climate-Isotope Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Y Bao
- Department of Geography, The Ohio State University, Columbus, OH, USA
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Simon MH, Ziegler M, Barker S, van der Meer MTJ, Schouten S, Hall IR. A late Pleistocene dataset of Agulhas Current variability. Sci Data 2020; 7:385. [PMID: 33177538 PMCID: PMC7659013 DOI: 10.1038/s41597-020-00689-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 09/23/2020] [Indexed: 11/09/2022] Open
Abstract
The interocean transfer of thermocline water between the Indian and the Atlantic Oceans known as 'Agulhas leakage' is of global significance as it influences the Atlantic Meridional Overturning Circulation (AMOC) on different time scales. Variability in the Agulhas Current regime is key in shaping hydroclimate on the adjacent coastal areas of the African continent today as well as during past climates. However, the lack of long, continuous records from the proximal Agulhas Current region dating beyond the last glacial cycle prevents elucidation of its role in regional and wider global climate changes. This is the first continuous record of hydrographic variability (SST; δ18Osw) from the Agulhas Current core region spanning the past 270,000 years. The data set is analytical sound and provides a solid age model. As such, it can be used by paleoclimate scientists, archaeologists, and climate modelers to evaluate, for example, linkages between the Agulhas Current system and AMOC dynamics, as well as connections between ocean heat transport and Southern African climate change in the past and its impact on human evolution.
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Affiliation(s)
- Margit H Simon
- NORCE Norwegian Research Centre, Bjerknes Centre for Climate Research, Jahnebakken 5, 5007, Bergen, Norway.
- Centre for Early Sapiens Behaviour (SapienCE), AHKR Institute, University of Bergen, Bergen, Norway.
| | - Martin Ziegler
- Department of Earth Sciences, Utrecht University, 3584, CD, Utrecht, Netherlands
| | - Stephen Barker
- School of Earth and Environmental Sciences, Cardiff University, Cardiff, CF10 3AT, United Kingdom
| | - Marcel T J van der Meer
- Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Den Burg, Netherlands
| | - Stefan Schouten
- Department of Earth Sciences, Utrecht University, 3584, CD, Utrecht, Netherlands
- Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Den Burg, Netherlands
| | - Ian R Hall
- School of Earth and Environmental Sciences, Cardiff University, Cardiff, CF10 3AT, United Kingdom
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Sánchez Goñi MF. Regional impacts of climate change and its relevance to human evolution. EVOLUTIONARY HUMAN SCIENCES 2020; 2:e55. [PMID: 37588361 PMCID: PMC10427484 DOI: 10.1017/ehs.2020.56] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The traditional concept of long and gradual, glacial-interglacial climate changes during the Quaternary has been challenged since the 1980s. High temporal resolution analysis of marine, terrestrial and ice geological archives has identified rapid, millennial- to centennial-scale, and large-amplitude climatic cycles throughout the last few million years. These changes were global but have had contrasting regional impacts on the terrestrial and marine ecosystems, with in some cases strong changes in the high latitudes of both hemispheres but muted changes elsewhere. Such a regionalization has produced environmental barriers and corridors that have probably triggered niche contractions/expansions of hominin populations living in Eurasia and Africa. This article reviews the long- and short-timescale ecosystem changes that have punctuated the last few million years, paying particular attention to the environments of the last 650,000 years, which have witnessed key events in the evolution of our lineage in Africa and Eurasia. This review highlights, for the first time, a contemporaneity between the split between Denisovan and Neanderthals, at ~650-400 ka, and the strong Eurasian ice-sheet expansion down to the Black Sea. This ice expansion could form an ice barrier between Europe and Asia that may have triggered the genetic drift between these two populations.
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44
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Badino F, Pini R, Bertuletti P, Ravazzi C, Delmonte B, Monegato G, Reimer P, Vallé F, Arrighi S, Bortolini E, Figus C, Lugli F, Maggi V, Marciani G, Margaritora D, Oxilia G, Romandini M, Silvestrini S, Benazzi S. The fast-acting "pulse" of Heinrich Stadial 3 in a mid-latitude boreal ecosystem. Sci Rep 2020; 10:18031. [PMID: 33093492 PMCID: PMC7581741 DOI: 10.1038/s41598-020-74905-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 09/29/2020] [Indexed: 11/10/2022] Open
Abstract
A 3800 year-long radiocarbon-dated and highly-resolved palaeoecological record from Lake Fimon (N-Italy) served to investigate the effects of potential teleconnections between North Atlantic and mid-to-low latitudes at the transition from Marine Isotope Stage (MIS) 3 to 2. Boreal ecosystems documented in the Fimon record reacted in a sensitive way to millennial and sub-millennial scale Northern Hemisphere atmospheric circulation patterns. The high median time-resolution of 58 years allows the identification of five abrupt event-boundaries (i.e., main forest expansion and decline excursions) synchronous with the sharp stadial/interstadial (GS/GI) transitions within dating uncertainties. During Heinrich Stadial 3 (HS 3) we reconstruct more open and dry conditions, compared to the other GS, with a dominant regional scale fire signal. Linkages between local fires and climate-driven fuel changes resulted in high-magnitude fire peaks close to GI/GS boundaries, even exacerbated by local peatland conditions. Finally, palaeoecological data from the HS 3 interval unveiled an internal variability suggesting a peak between 30,425 and 29,772 cal BP (2σ error) which matches more depleted δ18O values in alpine speleothems. We hypothesise that this signal, broadly resembling that of other mid-latitudes proxies, may be attributed to the southward shift of the Northern Hemisphere storm tracks and the associated delayed iceberg discharge events as documented during other HS.
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Affiliation(s)
- Federica Badino
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy. .,Research Group on Vegetation, Climate and Human Stratigraphy, Laboratory of Palynology and Palaeoecology, CNR-Institute of Environmental Geology and Geoengineering (IGAG), 20126, Milan, Italy.
| | - Roberta Pini
- Research Group on Vegetation, Climate and Human Stratigraphy, Laboratory of Palynology and Palaeoecology, CNR-Institute of Environmental Geology and Geoengineering (IGAG), 20126, Milan, Italy
| | - Paolo Bertuletti
- Research Group on Vegetation, Climate and Human Stratigraphy, Laboratory of Palynology and Palaeoecology, CNR-Institute of Environmental Geology and Geoengineering (IGAG), 20126, Milan, Italy.,Department of Environmental and Earth Sciences, University of Milano-Bicocca, 20126, Milan, Italy
| | - Cesare Ravazzi
- Research Group on Vegetation, Climate and Human Stratigraphy, Laboratory of Palynology and Palaeoecology, CNR-Institute of Environmental Geology and Geoengineering (IGAG), 20126, Milan, Italy
| | - Barbara Delmonte
- Department of Environmental and Earth Sciences, University of Milano-Bicocca, 20126, Milan, Italy
| | - Giovanni Monegato
- CNR-Institute of Geosciences and Earth Resources (IGG), 35131, Padua, Italy
| | - Paula Reimer
- School of Natural and Built Environment, Queen's University Belfast, Belfast, BT7 1NN, UK
| | - Francesca Vallé
- Department of Environmental and Earth Sciences, University of Milano-Bicocca, 20126, Milan, Italy
| | - Simona Arrighi
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy.,Dipartimento di Scienze Fisiche, della Terra e dell'Ambiente, Università di Siena, 53100, Siena, Italy
| | - Eugenio Bortolini
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy
| | - Carla Figus
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy
| | - Federico Lugli
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy.,Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, 41125, Modena, Italy
| | - Valter Maggi
- Department of Environmental and Earth Sciences, University of Milano-Bicocca, 20126, Milan, Italy
| | - Giulia Marciani
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy.,Dipartimento di Scienze Fisiche, della Terra e dell'Ambiente, Università di Siena, 53100, Siena, Italy
| | - Davide Margaritora
- Department of Environmental and Earth Sciences, University of Milano-Bicocca, 20126, Milan, Italy.,Dipartimento di Studi Umanistici, Sezione di Scienze Preistoriche e Antropologiche, Università di Ferrara, 44100, Ferrara, Italy
| | - Gregorio Oxilia
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy
| | - Matteo Romandini
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy.,Dipartimento di Studi Umanistici, Sezione di Scienze Preistoriche e Antropologiche, Università di Ferrara, 44100, Ferrara, Italy
| | - Sara Silvestrini
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy
| | - Stefano Benazzi
- Department of Cultural Heritage, University of Bologna, 48121, Ravenna, Italy.,Department of Human Evolution Max Planck Institute for Evolutionary Anthropology, 04103, Leipzig, Germany
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45
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Wolf A, Roberts WHG, Ersek V, Johnson KR, Griffiths ML. Rainwater isotopes in central Vietnam controlled by two oceanic moisture sources and rainout effects. Sci Rep 2020; 10:16482. [PMID: 33020586 PMCID: PMC7536182 DOI: 10.1038/s41598-020-73508-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 09/16/2020] [Indexed: 11/17/2022] Open
Abstract
The interpretation of palaeoclimate archives based on oxygen isotopes depends critically on a detailed understanding of processes controlling the isotopic composition of precipitation. In the summer monsoonal realm, like Southeast Asia, seasonally and interannually depleted oxygen isotope ratios in precipitation have been linked to the summer monsoon strength. However, in some regions, such as central Vietnam, the majority of precipitation falls outside the summer monsoon period. We investigate processes controlling stable isotopes in precipitation from central Vietnam by combining moisture uptake calculations with monthly stable isotope data observed over five years. We find that the isotopic seasonal cycle in this region is driven by a shift in moisture source from the Indian Ocean to the South China Sea. This shift is reflected in oxygen isotope ratios with low values (− 8 to − 10‰) during summer and high values during spring/winter (0 to − 3‰), while 70% of the annual rainfall occurs during autumn. Interannual changes in precipitation isotopes in central Vietnam are governed by the timing of the seasonal onset and withdrawal of the Intertropical Convergence Zone, which controls the amount of vapour contributed from each source.
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Affiliation(s)
- Annabel Wolf
- Department of Geography and Environmental Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK.
| | - William H G Roberts
- Department of Geography and Environmental Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK
| | - Vasile Ersek
- Department of Geography and Environmental Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK
| | - Kathleen R Johnson
- Department of Earth System Science, University of California, Irvine, CA, 92697, USA
| | - Michael L Griffiths
- Department of Environmental Science, William Paterson University, Wayne, NJ, 07470, USA
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46
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Abstract
Results of five climate model simulation studies on the Younger Dryas cold event (YD) are compared with a focus on temperature and precipitation. Relative to the Bølling-Allerød interstadial (BA), the simulations show consistent annual cooling in Europe, Greenland, Alaska, North Africa and over the North Atlantic Ocean and Nordic Seas with maximum reduction of temperatures being simulated over the oceans, ranging from −25 °C to −6 °C. Warmer conditions were simulated in the interior of North America. In two experiments, the mid-to-high latitudes of the Southern Hemisphere were also warmer, associated with a strong bi-polar seesaw mechanism in response to a collapse of the Atlantic meridional overturning circulation (AMOC). The modelled YD-BA temperature response was in general agreement with proxy-based evidence. The simulations reveal reduced YD-BA precipitation (up to 150 mm yr−1) over all regions with major cooling, and over the northern equatorial region. South of the equator, modelled precipitation seemed to increase due to a southward shift of the InterTropical Convergence Zone (ITCZ). The largest uncertainty in the YD is the high-latitude response, where the models show diverging results. This disagreement is partly related to uncertainties in the freshwater forcing. Most model studies assume an AMOC shutdown, but this is incompatible with proxy evidence.
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47
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Hao Q, Yang S, Song Z, Ran X, Yu C, Chen C, Van Zwieten L, Quine TA, Liu H, Wang Z, Wang H. Holocene carbon accumulation in lakes of the current east Asian monsoonal margin: Implications under a changing climate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 737:139723. [PMID: 32554037 DOI: 10.1016/j.scitotenv.2020.139723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 04/28/2020] [Accepted: 05/24/2020] [Indexed: 06/11/2023]
Abstract
Carbon (C) present in lake sediments is an important global sink for CO2; however, an in-depth understanding of the impact of climate variability and the associated changes in vegetation on sediment C dynamics is still lacking. A total of 13 lakes were studied to quantify the influence of climate and vegetation on the reconstructed Holocene C accumulation rate (CAR) in lake sediments of the modern East Asian monsoonal margin. The corresponding paleoclimate information was assessed, including the temperature (30-90°N in the Northern Hemisphere) and precipitation (indicated by the δ18O of the Sanbao, Dongge, and Hulu caves). The Holocene vegetation conditions were inferred by pollen records, including arboreal pollen/non-arboreal pollen and pollen percentages. The results showed that the peak CAR occurred during the mid-Holocene, coinciding with the strongest period of the East Asian summer monsoon and expansion of forests. Lakes in the temperate steppe (TS) regions had a mean CAR of 13.41 ± 0.88 g C m-2 yr-1, which was significantly greater than the CARs of temperate desert (TD) and highland meadow/steppe (HMS; 6.76 ± 0.29 and 7.39 ± 0.73 g C m-2 yr-1, respectively). The major influencing factor for the TS sub-region was vegetation dynamics, especially the proportion of arboreal vegetation, while temperature and vegetation coverage were more important for the HMS. These findings indicate that C accumulation in lake sediments is linked with climate and vegetation changes over long timescales; however, there was notable spatial heterogeneity in the CARs, such as opposing temporal changes and different major influencing factors among the three sub-regions during the mid-Holocene. Aridification and forest loss would decrease C storage. However, prediction of C accumulation remains difficult because of the spatial heterogeneity in CARs and the interaction between the CAR and various factors under future climate change conditions.
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Affiliation(s)
- Qian Hao
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China; School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Shilei Yang
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China; School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Zhaoliang Song
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China; School of Earth System Science, Tianjin University, Tianjin 300072, China.
| | - Xiangbin Ran
- Research Center for Marine Ecology, First Institute of Oceanography, State Oceanic Administration, Qingdao, Shandong 266061, China
| | - Changxun Yu
- Department of Biology and Environmental Science, Linnaeus University, SE-39182 Kalmar, Sweden
| | - Chunmei Chen
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China; School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Lukas Van Zwieten
- New South Wales Department of Primary Industries, 1243 Bruxner Highway, Wollongbar, NSW 2477, Australia
| | - Timothy A Quine
- Geography, Amory Building, University of Exeter, Rennes Drive, Exeter EX4 4RJ, United Kingdom
| | - Hongyan Liu
- College of Urban and Environmental Sciences, Peking University, Peking 100871, China
| | - Zhengang Wang
- School of Geography and Planning, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China
| | - Hailong Wang
- School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China; School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China
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48
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Dang H, Jian Z, Wang Y, Mohtadi M, Rosenthal Y, Ye L, Bassinot F, Kuhnt W. Pacific warm pool subsurface heat sequestration modulated Walker circulation and ENSO activity during the Holocene. SCIENCE ADVANCES 2020; 6:6/42/eabc0402. [PMID: 33055161 PMCID: PMC7556771 DOI: 10.1126/sciadv.abc0402] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 08/25/2020] [Indexed: 06/11/2023]
Abstract
Dynamics driving the El Niño-Southern Oscillation (ENSO) over longer-than-interannual time scales are poorly understood. Here, we compile thermocline temperature records of the Indo-Pacific warm pool over the past 25,000 years, which reveal a major warming in the Early Holocene and a secondary warming in the Middle Holocene. We suggest that the first thermocline warming corresponds to heat transport of southern Pacific shallow overturning circulation driven by June (austral winter) insolation maximum. The second thermocline warming follows equatorial September insolation maximum, which may have caused a steeper west-east upper-ocean thermal gradient and an intensified Walker circulation in the equatorial Pacific. We propose that the warm pool thermocline warming ultimately reduced the interannual ENSO activity in the Early to Middle Holocene. Thus, a substantially increased oceanic heat content of the warm pool, acting as a negative feedback for ENSO in the past, may play its role in the ongoing global warming.
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Affiliation(s)
- Haowen Dang
- State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China
| | - Zhimin Jian
- State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China.
| | - Yue Wang
- State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China
| | - Mahyar Mohtadi
- MARUM-Center for Marine Environmental Sciences, University of Bremen, 28359 Bremen, Germany
| | - Yair Rosenthal
- Department of Marine and Coastal Science and Department of Earth and Planetary Sciences, Rutgers University, New Brunswick, NJ 08901, USA
| | - Liming Ye
- Key Laboratory of Submarine Geosciences, Second Institute of Oceanography, Ministry of Natural Resources of China, Hangzhou 310012, China
| | - Franck Bassinot
- Laboratoire des Sciences du Climat et de l'Environnement/IPSL, CEA-CNRS-UVSQ, University Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Wolfgang Kuhnt
- Institute of Geosciences, Christian-Albrechts-University, D-24118 Kiel, Germany
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49
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Abstract
The Younger Dryas (YD), arguably the most widely studied millennial-scale extreme climate event, was characterized by diverse hydroclimate shifts globally and severe cooling at high northern latitudes that abruptly punctuated the warming trend from the last glacial to the present interglacial. To date, a precise understanding of its trigger, propagation, and termination remains elusive. Here, we present speleothem oxygen-isotope data that, in concert with other proxy records, allow us to quantify the timing of the YD onset and termination at an unprecedented subcentennial temporal precision across the North Atlantic, Asian Monsoon-Westerlies, and South American Monsoon regions. Our analysis suggests that the onsets of YD in the North Atlantic (12,870 ± 30 B.P.) and the Asian Monsoon-Westerlies region are essentially synchronous within a few decades and lead the onset in Antarctica, implying a north-to-south climate signal propagation via both atmospheric (decadal-time scale) and oceanic (centennial-time scale) processes, similar to the Dansgaard-Oeschger events during the last glacial period. In contrast, the YD termination may have started first in Antarctica at ∼11,900 B.P., or perhaps even earlier in the western tropical Pacific, followed by the North Atlantic between ∼11,700 ± 40 and 11,610 ± 40 B.P. These observations suggest that the initial YD termination might have originated in the Southern Hemisphere and/or the tropical Pacific, indicating a Southern Hemisphere/tropics to North Atlantic-Asian Monsoon-Westerlies directionality of climatic recovery.
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50
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Corrick EC, Drysdale RN, Hellstrom JC, Capron E, Rasmussen SO, Zhang X, Fleitmann D, Couchoud I, Wolff E. Synchronous timing of abrupt climate changes during the last glacial period. Science 2020; 369:963-969. [PMID: 32820122 DOI: 10.1126/science.aay5538] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 07/09/2020] [Indexed: 11/02/2022]
Abstract
Abrupt climate changes during the last glacial period have been detected in a global array of palaeoclimate records, but our understanding of their absolute timing and regional synchrony is incomplete. Our compilation of 63 published, independently dated speleothem records shows that abrupt warmings in Greenland were associated with synchronous climate changes across the Asian Monsoon, South American Monsoon, and European-Mediterranean regions that occurred within decades. Together with the demonstration of bipolar synchrony in atmospheric response, this provides independent evidence of synchronous high-latitude-to-tropical coupling of climate changes during these abrupt warmings. Our results provide a globally coherent framework with which to validate model simulations of abrupt climate change and to constrain ice-core chronologies.
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Affiliation(s)
- Ellen C Corrick
- School of Geography, The University of Melbourne, Melbourne, Victoria, Australia. .,EDYTEM, CNRS, Université Savoie Mont Blanc, Université Grenoble Alpes, Chambéry, France
| | - Russell N Drysdale
- School of Geography, The University of Melbourne, Melbourne, Victoria, Australia.,EDYTEM, CNRS, Université Savoie Mont Blanc, Université Grenoble Alpes, Chambéry, France
| | - John C Hellstrom
- School of Earth Science, The University of Melbourne, Melbourne, Victoria, Australia
| | - Emilie Capron
- British Antarctic Survey, Cambridge, UK.,Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Sune Olander Rasmussen
- Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Xu Zhang
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Center for Pan Third Pole Environment (Pan-TPE), Lanzhou University, Lanzhou, 730000, China.,Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, D-27570 Bremerhaven, Germany.,CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Dominik Fleitmann
- Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland
| | - Isabelle Couchoud
- EDYTEM, CNRS, Université Savoie Mont Blanc, Université Grenoble Alpes, Chambéry, France.,School of Geography, The University of Melbourne, Melbourne, Victoria, Australia
| | - Eric Wolff
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
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