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Nature Volume 599, Pages 239–244 (2021) Cite this article
The climate change of the past 24,000 years has provided key insights into the response of the Earth system to external forcing. Climate model simulations 1, 2 and proxy data 3, 4, 5, 6, 7, and 8 independently allow this critical interval to be studied; however, they sometimes come to very different conclusions. Here, we use paleoclimate data assimilation9,10 to use these two types of information to perform the first proxy-constrained full-field re-analysis of the surface temperature changes across the last glacial maximum, presented at a resolution of 200 years. We prove that the temperature changes in the past 24,000 years are related to two main climate mechanisms: the radiative forcing of ice sheets and greenhouse gases; and the superposition of ocean overturning circulation and seasonal changes in sunlight. Compared with the previous agent-based reconstruction6,7, our results show that since the early Holocene (about 9000 years ago), the global average temperature has increased slightly but steadily by about 0.5 °C. Compared with recent temperature changes11, our reanalysis shows that the speed and magnitude of modern warming are unusual compared to the changes in the past 24,000 years.
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All LGMR and related agency data are publicly available through the National Oceanic and Atmospheric Administration (NOAA) Paleoclimatology Data Archive (https://www.ncdc.noaa.gov/paleo/study/33112). This article provides source data.
The MATLAB code for reconstruction (DASH) is publicly available (https://github.com/JonKing93/DASH), and all accompanying Bayesian proxy forward models used in this study (BAYSPAR, BAYSPLINE, BAYFOX and BAYMAG ) Is the same (https://github.com/jesstierney). The iCESM1.2 model code can be obtained from https://github.com/NCAR/iCESM1.2.
Liu, Z. et al. Transient simulation of the last glacier melting using the new Bølling-Allerød warming mechanism. Science 325, 310–314 (2009).
ADS CAS PubMed PubMed Central Google Scholar
Liu, Z. et al. Holocene temperature problem. Process National Academy of Sciences. science. United States 111, E3501–E3505 (2014).
ADS CAS PubMed PubMed Central Google Scholar
Sha Kun, JD etc. Global warming before the increase in carbon dioxide concentration during the last deglacial period. Nature 484, 49–54 (2012).
ADS CAS PubMed PubMed Central Google Scholar
Snyder, CW The evolution of global temperature over the past 2 million years. Nature 538, 226–228 (2016).
ADS CAS PubMed PubMed Central Google Scholar
Bereiter, B., Shackleton, S., Baggenstos, D., Kawamura, K. & Severinghaus, J. Average global ocean temperature during the last glacier transition. Nature 553, 39–44 (2018).
ADS CAS PubMed PubMed Central Google Scholar
Marcott, SA, Shakun, JD, Clark, PU & Mix, AC Reconstruction of regional and global temperature over the past 11,300 years. Science 339, 1198–1201 (2013).
ADS CAS PubMed PubMed Central Google Scholar
Kaufman, D. et al. Holocene global average surface temperature, a multi-method reconstruction method. science. Data 7, 201 (2020).
CAS PubMed PubMed Central Google Scholar
Bova, S., Rosenthal, Y., Liu, Z., Godad, SP & Yan, M. The seasonal origin of the Holocene and last interglacial thermal criteria. Nature 589, 548–553 (2021).
ADS CAS PubMed PubMed Central Google Scholar
Hakim, GJ, etc. The last millennium climate reanalysis project: framework and preliminary results. J. Geophysics. Reservoir atmosphere. 121, 6745–6764 (2016).
Tierney, JE etc. Re-examine glacier cooling and climate sensitivity. Nature 584, 569–573 (2020).
ADS CAS PubMed PubMed Central Google Scholar
Morris, CP etc. An updated assessment of near-surface temperature changes since 1850: HadCRUT5 data set. J. Geophysics. Reservoir atmosphere. 126, e2019JD032361 (2020).
Marsicek, J., Shuman, BN, Bartlein, PJ, Shafer, SL & Brewer, S. Reconciling different trends in Holocene temperature and millennial changes. Nature 554, 92–96 (2018).
ADS CAS PubMed PubMed Central Google Scholar
Baggenstos, D. etc. The earth's radiation imbalance from the last ice age to the present. Process National Academy of Sciences. science. United States 116, 14881-14886 (2019).
ADS CAS PubMed PubMed Central Google Scholar
Kageyama, M. etc. PMIP4-CMIP6 Last Glacial Maximum Experiment: Preliminary Results and Comparison with PMIP3-CMIP5 Simulation. climate. The past 17 years, 1065-1089 (2021).
Brierley, CM, etc. PMIP4-CMIP6 Large-scale characteristics and evaluation of mid-Holocene simulations. climate. The past 16 years, from 1847 to 1872 (2020).
Park, H.-S., Kim, S.-J., Stewart, AL, Son, S.-W. & Seo, K.-H. Mid-Holocene northern hemisphere warming driven by Arctic amplification. science. Advanced 5. eaax8203 (2019).
ADS PubMed PubMed Central Google Scholar
Tardif, R. etc. Last Millennium Reanalysis with extended proxy database and seasonal proxy modeling. climate. The past 15 years, 1251-1273 (2019).
Bayesian spatial variation calibration model represented by Tierney, JE & Tingley, MP TEX86. Geochemistry. Cosmic chemistry. Journal 127, 83–106 (2014).
Tierney, JE & Tingley, MP BAYSPLINE: New calibration of enone ancient thermometer. Paleo-oceanography and paleo-climate. 33, 281–301 (2018).
Malevich, SB, Vetter, L. & Tierney, JE The global core top calibration of δ18o in planktonic foraminifera and sea surface temperature. Paleo-oceanography and paleo-climate. 34, 1292–1315 (2019).
Tierney, JE, Malevich, SB, Gray, W., Vetter, L. & Thirumalai, K. Bayesian calibration of magnesium/calcium ancient thermometers in planktonic foraminifera. Paleo-oceanography and paleo-climate. 34, 2005-2030 (2019).
Brady, E. etc. The connected isotope water cycle in version 1 of the community earth system model. J. Adv. Model. Earth System 11, 2547-2566 (2019).
Amrhein, DE, Hakim, GJ & Parsons, LA quantified the structural uncertainty in the assimilation of paleoclimate data and applied it for the past thousand years. Geophysics. Res. Wright. 47. e2020GL090485 (2020).
Köhler, P., Nehrbass-Ahles, C., Schmitt, J., Stocker, TF & Fischer, H. A 156 kyr smooths the history of atmospheric greenhouse gases CO2, CH4 and N2O and their radiative forcing. Earth system. science. Data 9, 363–387 (2017).
Braconnot, P. and Kageyama, M. Short-wave forcing and feedback in PMIP3 simulations of the Last Glacial Maximum and Mid-Holocene. Philos. Translated by R. Soc. A 373, 20140424 (2015).
Berger, A. Long-term changes in daily sunshine and quaternary climate change. J. Atmosphere. science. 35, 2362–2367 (1978).
Huybers, P. & Denton, G. Antarctic temperature on an orbital time scale controlled by the duration of the local summer. Nat. Earth Science. 1, 787–792 (2008).
Inbury, J. et al. Regarding the structure and origin of the main glacier cycles 1. Linear response to Milankovitch forcing. Paleooceanography 7, 701–738 (1992).
McManus, JF, Francois, R., Gherardi, J.-M., Keigwin, LD & Brown-Leger, S. The collapse and rapid recovery of the Atlantic meridional circulation associated with deglaciation climate change. Nature 428, 834–837 (2004).
ADS CAS PubMed PubMed Central Google Scholar
Böhm, E. etc. The strong and deep Atlantic meridional overturning circulation during the last glacial cycle. Nature 517, 73–76 (2015).
ADS PubMed PubMed Central Google Scholar
Lippold, J. et al. Constrain the variability of the Atlantic meridional overturning circulation during the Holocene. Geophysics. Res. Wright. 46, 11338–11346 (2019).
Shakun, JD & Carlson, AE A global perspective on climate change from the Last Glacial Maximum to the Holocene. Quaternary ammonium salt. science. Rev. 29, 1801–1816 (2010).
Clark, PU etc. The global climate evolution during the last deglacial period. Process National Academy of Sciences. science. United States 109, E1134–E1142 (2012).
CAS PubMed PubMed Central Google Scholar
Pedro, JB etc. Beyond the bipolar seesaw: understanding the process of coupling between hemispheres. Quaternary ammonium salt. science. Rev. 192, 27–46 (2018).
He, F. etc. The northern hemisphere’s forcing of the southern hemisphere’s climate during the last deglaciation. Nature 494, 81–85 (2013).
Ritz, SP, Stocker, TF, Grimalt, JO, Menviel, L. & Timmermann, A. Estimated intensity of the Atlantic overturning circulation during the last glacier retreat. Nat. Earth Science. 6, 208–212 (2013).
Praetorius, SK, etc. The role of the Northeast Pacific meltwater event in deglaciation climate change. science. Advanced 6. eaay2915 (2020).
ADS CAS PubMed PubMed Central Google Scholar
Gray, WR, etc. The wind-driven evolution of the North Pacific subpolar circulation during the last deglacial period. Geophysics. Reservoir Lett.47, e2019GL086328 (2020).
Remer, PJ and others. IntCal13 and Marine13 radiocarbon age calibration curve 0–50,000 years cal BP. Radiocarbon 55, 1869–1887 (2013).
Blaauw, M. & Christen, JA uses a flexible depth model of paleoclimatic age using autoregressive gamma process. Bayesian anal. 6, 457–474 (2011).
Lokanini, RA etc. The 2013 World Ocean Atlas. Volume 1, Temperature (NOAA, 2013).
Wang, KJ, etc. Group 2i Isochrysis produces characteristic ketenes that reflect the distribution of sea ice. Nat. Community. 12, 15 (2021).
ADS PubMed PubMed Central Google Scholar
Sachs, JP Cooling in the waters of the northwest Atlantic slope during the Holocene. Geophysics. Res. Wright. 34, L03609 (2007).
Tierney, JE, Haywood, AM, Feng, R., Bhattacharya, T. & Otto-Bliesner, BL Pliocene warming is consistent with greenhouse gas forcing. Geophysics. Res. Wright. 46, 9136-9144 (2019).
Reina, NA etc. Global analysis of sea surface temperature, sea ice and night ocean temperature since the late 19th century. J. Geophysics. Reservoir 108, 4407 (2003).
Gray, WR and Evans, D. The effect of non-thermal on Mg/Ca in planktonic foraminifera: A review of the cultivation research and application of the last glacial peak. Paleo-oceanography and paleo-climate. 34, 306–315 (2019).
Lambeck, K., Rouby, H., Purcell, A., Sun, Y. & Sambridge, M. Sea level and global ice volume from the last glacial maximum to the Holocene. Process National Academy of Sciences. science. United States 111, 15296–15303 (2014).
ADS CAS PubMed PubMed Central Google Scholar
Monnin, E. et al. The atmospheric CO2 concentration at the end of the last ice age. Science 291, 112–114 (2001).
ADS CAS PubMed PubMed Central Google Scholar
MacFarling Meure, C. etc. Law Dome CO2, CH4, and N2O ice core records have been extended to 2000 BP. Geophysics. Res. Wright. 33, L14810 (2006).
Rubino, M. etc. The revised 1000 year 13C-CO2 record of the Law Dome in Antarctica and Antarctica. J. Geophysics. Reservoir atmosphere. 118, 8482–8499 (2013).
Marcotte, SA etc. The hundred-year scale change of the global carbon cycle during the last deglaciation. Nature 514, 616–619 (2014).
ADS CAS PubMed PubMed Central Google Scholar
Ahn, J. & Brook, EJ Siple Dome Ice reveals two patterns of carbon dioxide changes in the millennium of the last ice age. Nat. Community. 5, 3723 (2014).
ADS CAS PubMed PubMed Central Google Scholar
Bereiter, B. etc. Before changing the EPICA Dome C CO2 record from 800 to 600 kyr. Geophysics. Res. Wright. 42, 542–549 (2015).
Olsen, A. et al. Global Ocean Data Analysis Project Version 2 (GLODAPv2)-a consistent data product within the world's oceans. Earth system. science. Data 8, 297–323 (2016).
Lisiecki, LE & Raymo, ME A stack of 57 globally distributed benthic δ18O records in the Pliocene-Pleistocene. Paleooceanography 20, PA1003 (2005).
Schrag, DP, Hampt, G. & Murray, DW Pore fluid limits the temperature and oxygen isotopic composition of the glacier ocean. Science 272, 1930–1932 (1996).
ADS CAS PubMed PubMed Central Google Scholar
LeGrande, AN & Schmidt, GA Global grid dataset of oxygen isotopes in seawater. Geophysics. Res. Wright. 33, L12604 (2006).
Zhu, J., Poulsen, CJ & Tierney, JE simulated extreme warmth and high climate sensitivity of the Eocene through cloud feedback. science. Advanced 5. eaax1874 (2019).
ADS CAS PubMed PubMed Central Google Scholar
Herrell, JW et al. Community Earth System Model: A collaborative research framework. bull. Yes. meteorological. society. 94, 1339–1360 (2013).
Meehl, GA etc. The impact of model resolution, physics and coupling on storm tracks in the Central and Southern Hemisphere of CESM1.3. Geophysics. Res. Wright. 46, 12408–12416 (2019).
Zhu, J. et al. An earth system model with isotope enabled shows reduced ENSO variability for LGM. Geophysics. Res. Wright. 44, 6984–6992 (2017).
Stevenson, S. et al. The characteristics of volcanic eruptions using isotopes in the last millennium. Paleo-oceanography and paleo-climate. 34, 1534–1552 (2019).
Lüthi, D. etc. High-resolution carbon dioxide concentration records from 650,000-800,000 years ago. Nature 453, 379–382 (2008).
ADS PubMed PubMed Central Google Scholar
Loulergue, L. et al. The orbit and millennium-scale characteristics of atmospheric CH4 in the past 800,000 years. Nature 453, 383–386 (2008).
ADS CAS PubMed PubMed Central Google Scholar
Schilt, A. et al. Nitrous oxide in the atmosphere for the past 140,000 years. Earth planet. science. Wright. 300, 33–43 (2010).
Peltier, WR, Argus, DF & Drummond, R. Spatial geodesy limits glacier melting at the end of the ice age: the global ICE-6G_C (VM5a) model. J. Geophysics. Reservoir Solid Earth 120, 450–487 (2015).
DiNezio, PN, etc. The Indian Ocean amplifies glacial changes in tropical climates. science. Advanced 4. eaat9658 (2018).
ADS PubMed PubMed Central Google Scholar
Duplessy, JC, Labeyrie, L. & Waelbroeck, C. Limitations on the enrichment of ocean oxygen isotopes between the Last Glacial Maximum and the Holocene: Paleooceanographic implications. Quaternary ammonium salt. science. Rev. 21, 315–330 (2002).
Kageyama, M. etc. The contribution of PMIP4 to CMIP6-Part 4: The scientific goals and experimental design of the PMIP4-CMIP6 last glacial maximum experiment and the PMIP4 sensitivity experiment. Earth Science. Model Development 10, 4035–4055 (2017).
Otto-Bliesner, BL etc. PMIP4's contribution to CMIP6-Part 2: Two interglacial periods, scientific goals and experimental design for Holocene and last interglacial simulations. Earth Science. Model development 10, 3979–4003 (2017).
Lawrence, DM etc. Parametric improvements and functional and structural improvements in the 4th edition of the community land model. J. Advanced model. Earth System 3, M03001 (2011).
Bartlein, PJ & Shafer, SL Time slice and paleocalendar effect adjustment in transient climate model simulation (PaleoCalAdjust v1.0): The influence and strategy of data analysis. Earth Science. Model Development 12, 3889–3913 (2019).
Whitaker, JS & Hamill, TM Integrated data assimilation for undisturbed observations. Monday Weather Rev. 130, 1913–1924 (2002).
Hamill, TM is used to verify the interpretation of the rank histogram for ensemble prediction. Monday Weather Rev. 129, 550–560 (2001).
Jones, TR etc. Diffusion of water isotopes in the WAIS Divide ice core during the Holocene and the last ice age. J. Geophysics. Reservoir on the surface of the earth 122, 290–309 (2017).
Sokratov, SA & Golubev, VN Snow isotope content changes due to sublimation. J. Glaciol. 55, 823–828 (2009).
Comas-Bru, L. etc. Use the global climate change comprehensive record assessment model output since the last glacier. climate. The past 15 years, 1557-1579 (2019).
Atsawawaranunt, K. etc. SISAL database: a global resource that records the oxygen and carbon isotope records of cave animals. Earth system. science. Data 10, 1687–1713 (2018).
Blunier, T. & Brook, EJ The time of millennial-scale climate change in Antarctica and Greenland during the last ice age. Science 291, 109–112 (2001).
ADS CAS PubMed PubMed Central Google Scholar
Steinney, B. et al. The expression of the bipolar seesaw in the Antarctic climate record during the last deglaciation. Nat. Earth Science. 4, 46–49 (2011).
Watanabe, O. etc. The uniform climate change in eastern Antarctica over the past three glacial cycles. Nature 422, 509–512 (2003).
ADS CAS PubMed PubMed Central Google Scholar
Brook, EJ, etc. The time of millennium-scale climate change in the Siple Dome in western Antarctica was in the last ice age. Quaternary ammonium salt. science. Rev. 24, 1333–1343 (2005).
Steinney, B. et al. Deuterium excess records of EPICA Dome C and Dronning Maud Land ice core (Eastern Antarctica). Quaternary ammonium salt. science. Rev. 29, 146–159 (2010).
Steiger, EJ, etc. Simultaneous climate change in Antarctica and the North Atlantic. Science 282, 92–95 (1998).
ADS CAS PubMed PubMed Central Google Scholar
Small, JR etc. The climate and atmospheric history of the Vostok ice core in Antarctica over the past 420,000 years. Nature 399, 429–436 (1999).
Markle, BR etc. Global atmospheric teleconnection during the Dansgaard-Oeschger event. Nat. Earth Science. 10, 36-40 (2017).
Vinther, BM, etc. Synchronize the ice cores of the Renland and Agassiz ice sheets to the Greenland ice core chronology. J. Geophysics. Reservoir atmosphere. 113, D08115 (2008).
Stuiver, M. & Grootes, PM GISP2 Oxygen isotope ratio. Quaternary ammonium salt. Reservoir 53, 277–284 (2000).
Johnson, SJ et al. The δ18O record along the deep ice core of the Greenland Ice Core Project and possible climate instability in Imia. J. Geophysics. Reservoir Ocean 102, 26397–26410 (1997).
Andersen, KK, etc. A high-resolution record of the northern hemisphere climate extending to the last interglacial period. Nature 431, 147–151 (2004).
ADS CAS PubMed PubMed Central Google Scholar
Holmgren, K. et al. The millennium-scale climate change that has continued in Southern Africa over the past 25,000 years. Quaternary ammonium salt. science. Rev. 22, 2311–2326 (2003).
Novello, VF, etc. The high-resolution history of the South American monsoon from the last glacial maximum to the Holocene. science. Representative 7, 44267 (2017).
ADS PubMed PubMed Central Google Scholar
Cheng, H. et al. Climate change in the northern Levant in the past 20,000 years. Geophysics. Res. Wright. 42, 8641–8650 (2015).
Dutt, S. etc. BP Geophys 33,800-5500 The sudden change in the intensity of the Indian summer monsoon. Res. Wright. 42, 5526–5532 (2015).
Alif, LK et al. During the last glacier retreat, the climate of the northern and southern hemispheres was quickly connected through the Australian monsoon. Nat. Community. 4, 2908 (2013).
ADS PubMed PubMed Central Google Scholar
Partin, JW, Cobb, KM, Adkins, JF, Clark, B. & Fernandez, DP Millennium-scale trends in the hydrology of the Western Pacific Warm Pool since the Last Glacial Maximum. Nature 449, 452–455 (2007).
ADS CAS PubMed PubMed Central Google Scholar
Cai, Y. etc. Inferred changes in Indian monsoon precipitation by stalagmites over the past 252,000 years. Process National Academy of Sciences. science. United States 112, 2954–2959 (2015).
ADS CAS PubMed PubMed Central Google Scholar
Fleitmann, D. et al. Temporal and climatic effects of the Greenland discontinuity recorded in stalagmites in northern Turkey. Geophysics. Res. Wright. 36, L19707 (2009).
Cruz, FW etc. Changes in atmospheric circulation driven by sunshine in tropical Brazil over the past 116,000 years. Nature 434, 63–66 (2005).
ADS CAS PubMed PubMed Central Google Scholar
Hellstrom, J., McCulloch, M. and Stone, J. Detailed 31,000-year climate and vegetation change records, from isotopic geochemistry of two New Zealand caves. Quaternary ammonium salt. Reservoir 50, 167–178 (1998).
Grant, KM etc. The rapid coupling between ice volume and polar temperature over the past 150,000 years. Nature 491, 744–747 (2012).
ADS CAS PubMed PubMed Central Google Scholar
Cheng, H. et al. Climate change patterns and biodiversity in the Amazon. Nat. Community. 4, 1411 (2013).
ADS PubMed PubMed Central Google Scholar
We thank B. Malevich for the early discussion and exploration of LGM to the current data assimilation, and thank M. Fox and N. Rapp for their help in compiling proxy data. We thank P. DiNezio for providing initial and boundary condition files for CESM simulations, and B. Markle for assisting in compiling and sharing ice core water isotope data. This research was supported by National Science Foundation (NSF) grant numbers AGS-1602301 and AGS-1602223 and Heising-Simons Foundation grant numbers 2016-012, 2016-014, and 2016-015. The CESM project is mainly supported by NSF. This material is based on work supported by the National Center for Atmospheric Research, which is the main facility sponsored by NSF under the Cooperation Agreement No. 1852977. Computing and data storage resources, including the Cheyenne Supercomputer (https://doi.org/ 10.5065/D6RX99HX), are provided by NCAR's Computing and Information Systems Laboratory (CISL).
Department of Earth Sciences, University of Arizona, Tucson, Arizona, USA
Matthew B. Osman, Jessica E. Tierney and Jonathan King
Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, Colorado, USA
Department of Atmospheric Sciences, University of Washington, Seattle, Washington, USA
Robert Tadif and Gregory J. Hakim
Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan, USA
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MBO performed data assimilation, led the analysis and interpretation of the results, and designed graphics. MBO and JET led the writing of this article. JET dominates the compilation of proxy data. JK wrote DASH code based on RT and GJHJZ method and input, CJP planned and performed iCESM simulation. All authors participated in the design of this study and the writing of this manuscript.
Correspondence with Matthew B. Osman.
The author declares no competing interests.
Peer review information Nature thanks William Gray and other anonymous reviewers for their contributions to the peer review of this work. Peer review reports are available.
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a. Histogram of recording resolution (representing the median sample resolution of each recording), calculated for each proxy type. b. Histogram of record length for each agent type.
a, starting from the left: using posterior data assimilation estimation, the average value of δ18Oc observed for each site and the average value of δ18Oc for forward modeling. Shown on the right are the relevant median R2 verification scores (each based on n = ~100 LGMR ensemble members), calculated by site (see Methods section "Internal and External Verification Tests"). b–d, same as a, but for \({\text{U}}_{37}^{\text{K'}}\) (b), Mg/Ca (c) and TEX86 (d), respectively.
a, 3 ka-pre-industrial (PI; 0 ka) and post-industrial Δδ18Op field; the overlying mark shows the observed 3 ka–PI Δδ18Op values from caves and ice cores. Only records that span at least 18 of the past 24 kyr are displayed. The ∆R2 and ∆RMSEP values represent the changes in the observed and post-assimilated ∆δ18Op values relative to the previous (iCESM) estimate. b–h, the same as in a, but the values are different between 6, 9, 12, 14, 16, 18, and 21 ka and PI. I, all observed Δδ18Op and model prior values; the dotted line indicates the 1:1 relationship. j, the relationship between all the observed ∆δ18Op and the posterior value, which shows that ∆R2 and ∆RMSEP are greatly improved than before. Please note that each scatter point displayed in panels i and j corresponds to the external verification site displayed in panel ah.
The uncertainty range represents the ±1σ level (dark) and 95% confidence range (bright) from the LGMR set. The full range (shaded in gray) and median iCESM time slice prior value (50-year average) for each site are also shown for comparison. See also extended data sheet 2.
ac, the correlation between surface air temperature (SAT) and greenhouse gas combination 24 and global albedo radiative forcing 13 (a) of spatial LGM to the present; summer length at 65°S; 27 (b); and rise from Bermuda The –1 × 231Pa/230Th AMOC proxy index 29, 30, 31 (c; shows that the SAT correlation is positively correlated with AMOC intensity).
a, δ18Oc, \({\text{U}}_{37}^{\text{K'}}\) and Mg/Ca-derived GMST reconstruction, using proxy-only (PO) and data-derived assimilation (DA ) method. In a, the shaded area shows the ±1σ range of n = 50 set members based on the DA-based GMST estimate, and the n = 10,000 realizations based on the PO-based GMST estimate (note that the dotted line curve does not show the uncertainty range). b. The sensitivity of Holocene GMST evolution to the removal of agents located in the adjacent 15° latitude zone, regardless of the PO or DA method. c. The sensitivity of DA-based Holocene GMST evolution to proxy seasonality (by fixing the growth seasonality of foraminifera to pre-industrial (PI) or LGM monthly SST Mg/Ca and δ18Oc, or by deleting seasonality Enone production records are used to calculate \({ \text{U}}_{37}^{\text{K'}}\) ), as well as the SST calibration of the "pooled" foraminifera species in the references. 20,21 (see supplementary information). All ∆GMST time series represent deviations from the past 2 kyr.
The collective distribution (n = 500) of the Northern Hemisphere (NH; red) and Southern Hemisphere (SH; blue) estimated by LGMR represents the average hemispheric temperature during the past 24 kyr. The top display shows the spatial difference in surface temperature between Bølling-Allerød (BA) and Younger Dryas (YD). The range of the start time of the last and interglacial period of the hemisphere is shown as the bottom histogram. LGMR is plotted together with the reconstructed decadal hemispheric temperature from the last millennium reanalysis v2.117 and HadCRUT5 observation products.
This file contains supplementary information sections 1–5.
Osman, MB, Tierney, JE, Zhu, J. etc. The globally resolved surface temperature since the last glacial maximum. Nature 599, 239–244 (2021). https://doi.org/10.1038/s41586-021-03984-4
DOI: https://doi.org/10.1038/s41586-021-03984-4
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