.2023 Jan 31;120(5):e2214655120.

doi: 10.1073/pnas.2214655120. Epub 2023 Jan 23.

CO₂-forced Late Miocene cooling and ecosystem reorganizations in East Asia

Yixiong Wen^{1 2}, Laiming Zhang^{1 2}, Ann E Holbourn³, Chenguang Zhu⁴, Katharine W Huntington⁵, Tianjie Jin^{1 2}, Yalin Li^{1 2}, Chengshan Wang^{1 2}

Affiliations

¹ State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China.
² School of the Earth Science and Resources, China University of Geosciences, Beijing 100083, China.
³ Institute of Geosciences, Christian-Albrechts-University, Kiel D-24118, Germany.
⁴ School of Environmental Studies, China University of Geosciences, Wuhan 430074, China.
⁵ Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195, USA.

PMID:36689658
PMCID: PMC9945954
DOI: 10.1073/pnas.2214655120

CO₂-forced Late Miocene cooling and ecosystem reorganizations in East Asia

Yixiong Wen et al. Proc Natl Acad Sci U S A.2023.

.2023 Jan 31;120(5):e2214655120.

doi: 10.1073/pnas.2214655120. Epub 2023 Jan 23.

Authors

Yixiong Wen^{1 2}, Laiming Zhang^{1 2}, Ann E Holbourn³, Chenguang Zhu⁴, Katharine W Huntington⁵, Tianjie Jin^{1 2}, Yalin Li^{1 2}, Chengshan Wang^{1 2}

Affiliations

¹ State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China.
² School of the Earth Science and Resources, China University of Geosciences, Beijing 100083, China.
³ Institute of Geosciences, Christian-Albrechts-University, Kiel D-24118, Germany.
⁴ School of Environmental Studies, China University of Geosciences, Wuhan 430074, China.
⁵ Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195, USA.

PMID:36689658
PMCID: PMC9945954
DOI: 10.1073/pnas.2214655120

Abstract

In parallel with pronounced cooling in the oceans, vast areas of the continents experienced enhanced aridification and restructuring of vegetation and animal communities during the Late Miocene. Debate continues over whetherpCO₂-induced global cooling was the primary driver of this climate and ecosystem upheaval on land. Here we present an 8 to 5 Ma land surface temperatures (LST) record from East Asia derived from paleosol carbonate clumped isotopes and integrated with climate model simulations. The LST cooled by ~7 °C between 7.5 and 5.7 Ma, followed by rapid warming across the Miocene-Pliocene transition (5.5 to 5 Ma). These changes occurred synchronously with variations in alkenone and Mg/Ca-based sea surface temperatures and with hydroclimate and ecosystem shifts in East Asia, highlighting a global climate forcing mechanism. Our modeling experiments additionally demonstrate thatpCO₂-forced cooling would have altered moisture transfer and pathways and driven extensive aridification in East Asia. We, thus, conclude that the East Asian hydroclimate and ecosystem shift was primarily controlled bypCO₂-forced global cooling between 8 and 5 Ma.

Keywords: Chinese Loess Plateau; Late Miocene cooling; climate modeling; clumped isotope; land surface temperature.

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Conflict of interest statement

The authors declare no competing interest.

Figures

**Fig. 1.**
LST versus compiled SST, foraminiferal δ¹⁸O, δ¹³C andpCO₂ evolution between 8 and 5 Ma. (A) Location of the CLP (square) in East Asia. Colored circles indicate the locations of records used in the global comparison shown in Figs. 1 and 2. (B) Clumped isotope (Δ₄₇)-derived LST from the northern CLP, combined new data, and recalibrated published data from ref. (18), error bars = 1 SE. The dashed line marks the present MAST in the study area. (C) Standardized tropical (red circles in Fig. 1A), mid-latitude (30 to 50°N/S; orange circles), and high-latitude (>50°N; blue circles) SST composite records during the 8 to 5 interval (seeMethod inSupplemental note 2 andSI Appendix, Figs. S6 and S7). Source data are shown inDataset S2. (D) Evolution of planktic foraminiferal δ¹⁸O at ODP Site 1146 in the South China Sea (3). The TG22-TG12 events indicate peak glacial stages (19). (E) Gradient (Δδ¹³C) between benthic and planktic foraminiferal δ¹³C in ODP Site 1146 (3). (F) δ¹¹B (20, 21) and alkenone-based (22, 23)pCO₂ estimations. Smooth curve fitted in Fig. 1C using locally weighted least squared error (LOWESS) method. The blue bar indicates the development of transient Northern Hemisphere ice sheets (19, 24).

**Fig. 2.**
Comparison of terrestrial temperature evolution with hydrological and ecological changes between 8 and 5 Ma. (A) Clumped isotope (Δ₄₇)-derived LST from the northern CLP, combined new data, and recalibrated published data from ref. . (B) Eolian dust fluxes recorded in ODP Sites 885 (31), 1208 (32) and 1146 (33). Note: the dust fluxes in ODP Site 885 may require further revision following Abell et al. (36). (C) Hydrological evolution of EASM, recorded in the SCS indicated by chemical weathering intensity (CIA and Rb/Sr, 29), δ¹⁸O_seawater (37), and alkenone C₃₇ concentration (38). Note: the records of chemical weathering intensity may also potentially be impacted by the onset of the Taiwan Orogeny at ~5 Ma (38). (D) Evolution of mollusk species in the CLP (34), mammal species in Pakistan of Southeast Asia (updated from ref. 12), and disappearance time of hominoid lineages in South China (rhomb, 35). (E) Range of tooth enamel δ¹³C from North American below 37°N (shading, 10); δ¹³C of leaf wax C₃₁n-alkane in ODP Site 718 (30). (F) C₄ diet of ungulates from China (shading, 9); minimum C₄ grasses (%) estimation from CLP phytolith (17), and δ¹³C of C₃₁n-alkane from ODP Site 722 (39). Smooth curve fitted using ten-point LOWESS method.

**Fig. 3.**
Simulated changes in summer (June-July-August) precipitation and circulation over East Asia whenpCO₂ is decreased from 400 ppm to 284 ppm and then to 142 ppm. (A andB) changes in summer precipitation (shaded, unit: mm/d) and wind fields (vectors, unit: m/s) at 850 hPa. (C andD) changes in summer vertically integrated moisture transport (vectors, units: kg m⁻¹ s⁻¹) and vapor divergence (shaded, units: 10⁻⁵ kg m⁻² s⁻¹).

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References

1. Steinthorsdottir M., et al. , The Miocene: The future of the past. Paleoceanogr. Paleoclimatol. 36, e2020PA004037 (2021).
1. Herbert T. D., et al. , Late Miocene global cooling and the rise of modern ecosystems. Nat. Geosci. 9, 843–847 (2016).
1. Holbourn A. E., et al. , Late Miocene climate cooling and intensification of southeast Asian winter monsoon. Nat. Commun. 9, 1–13 (2018). - PMC - PubMed
1. LaRiviere J. P., et al. , Late Miocene decoupling of oceanic warmth and atmospheric carbon dioxide forcing. Nature 486, 97–100 (2012). - PubMed
1. Schuster M., et al. , The age of the Sahara Desert. Science 311, 821 (2006). - PubMed

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CO₂-forced Late Miocene cooling and ecosystem reorganizations in East Asia

Affiliations

CO₂-forced Late Miocene cooling and ecosystem reorganizations in East Asia

Authors

Affiliations

Abstract

Conflict of interest statement

Figures

References

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