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Holocene climatic optimum

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The Holocene Climate Optimum (HCO) was a warm period in the first half of the Holocene epoch, that occurred in the interval roughly 9,500 to 5,500 years BP,[1] with a thermal maximum around 8000 years BP. It has also been known by many other names, such as Altithermal, Climatic Optimum, Holocene Megathermal, Holocene Optimum, Holocene Thermal Maximum, Holocene global thermal maximum, Hypsithermal, and Mid-Holocene Warm Period.

The warm period was followed by a gradual decline, of about 0.1 to 0.3 °C per millennium, until about two centuries ago. However, on a sub-millennial scale, there were regional warm periods superimposed on this decline.[2][3][4]

Global effects

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Temperature variations during the Holocene from a collection of different reconstructions and their average. The most recent period is on the right, but the recent warming is seen only in the inset.

The HCO was approximately 4.9 °C warmer than the Last Glacial Maximum.[5] A study in 2020 estimated that the average global temperature during the warmest 200 year period of the HCO, around 6,500 years ago, was around 0.7 °C warmer than the mean for nineteenth century AD, immediately before the Industrial Revolution, and 0.3 °C cooler than the average for 2011-2019.[6] The 2021 IPCC report expressed medium confidence that temperatures in the last decade are higher than they were in the Mid-Holocene Warm Period.[7] Temperatures in the Northern Hemisphere are simulated to be warmer than present average during the summers, but the tropics and parts of the Southern Hemisphere were colder than average.[8] The average temperature change appears to have declined rapidly with latitude and so essentially no change in mean temperature is reported at low and middle latitudes. Tropical reefs tend to show temperature increases of less than 1 °C. The tropical ocean surface at the Great Barrier Reef about 5350 years ago was 1 °C warmer and enriched in 18O by 0.5 per mil relative to modern seawater.[9]

Temperatures during the HCO were higher than in the present by around 6 °C in Svalbard, near the North Pole.[10]

Of 140 sites across the western Arctic, there is clear evidence for conditions that were warmer than now at 120 sites. At 16 sites for which quantitative estimates have been obtained, local temperatures were on average 1.6±0.8 °C higher during the optimum than now. Northwestern North America reached peak warmth first, from 11,000 to 9,000 years ago, but the Laurentide Ice Sheet still chilled eastern Canada. Northeastern North America experienced peak warming 4,000 years later. Along the Arctic Coastal Plain in Alaska, there are indications of summer temperatures 2–3 °C warmer than now.[11] Research indicates that the Arctic had less sea ice than now.[12] The Greenland Ice Sheet thinned, particularly at its margins.[13]

Northwestern Europe experienced warming, but there was cooling in Southern Europe.[14] In the southwestern Iberian Peninsula, forest cover reached its peak between 9,760 and 7,360 years BP as a result of high moisture availability and warm temperatures during the HCO.[15] In Central Europe, the HCO was when human impact on the environment first became clearly detectable in sedimentological records,[16] with the portion of the HCO from 9,000 to 7,500 BP being associated with minimal human impact and environmental stability, the portion from 7,500 to 6,300 BP with human impact only observed in pollen records, and the portion after 6,300 BP with substantial human influence on the environment.[17]

In the Middle East, the HCO was associated with frost-free winters and abundant Pistacia savannas. It was during this interval that the domestication of cereals and Neolithic population growth occurred in the region.[18]

The onset of the HCO in the southern Ural Mountains was simultaneous with that in Northern Europe, while its termination occurred between 6,300 and 5,100 BP.[19] Winter warming of 3 to 9 °C and summer warming of 2 to 6 °C occurred in northern central Siberia.[20]

The HCO was highly asynchronous in Central and East Asia,[21] though it at least occurred contemporaneously in the Loess Plateau, the Inner Mongolian Plateau, and Xinjiang.[22] As a result of rising sea levels and decay of ice sheets in the Northern Hemisphere, the East Asian Summer Monsoon (EASM) rain belt expanded to the northwest, penetrating deep into the Asian interior.[23] The EASM, being significantly weaker before and after the HCO, peaked in strength during this interval,[24] though the exact timing of its maximum intensity varied by region;[25] intensified westerlies occasionally caused dry spells in China during the HCO.[26] Current desert regions of Central Asia were extensively forested because of higher rainfall, and the warm temperate forest belts in China and Japan were extended northwards.[27] In the Yarlung Tsangpo valley of southern Tibet, precipitation was up to twice as high as it is today during the middle Holocene.[28] In the Huai River basin, the HCO began 9,100 to 8,000 BP.[29] Pollen records from Lake Tai in Jiangsu, China shed light on increased summer precipitation and a warmer and wetter overall climate in the region.[30] The stability of the Middle Holocene climate in China fostered the development of agriculture and animal husbandry in the region.[31] In the Korean Peninsula, arboreal pollen records the HCO as occurring from 8,900 to 4,400 BP, with its core period being 7,600 to 4,800 BP.[32] Sea levels in the Sea of Japan were 2-6 metres higher than in the present, with sea surface temperatures being 1-2 °C higher. The East Korea Warm Current reached as far as Primorye and pushed cold water off of the cooler Primorsky Current to the northeast. The Tsushima Current warmed the northern shores of Hokkaido penetrated into the Sea of Okhotsk.[33] In the northern South China Sea, the HCO was associated with colder winters due to a stronger East Asian Winter Monsoon (EAWM), causing frequent coral die-offs.[34]

In the Indian Subcontinent, the Indian Summer Monsoon (ISM) heavily intensified, creating a hot and wet climate in India along with high sea levels.[35]

Relative sea level in the Spermonde Archipelago was approximately 0.5 metres higher than it is today.[36][37] Sedimentary infill of lagoons was retarded by the sea level highstand and accelerated after the HCO, when sea levels dropped.[38]

Vegetation and water bodies in northern and central Africa in the Eemian (bottom) and Holocene (top)

West African sediments additionally record the African humid period, an interval between 16,000 and 6,000 years ago during which Africa was much wetter than now. That was caused by a strengthening of the African monsoon by changes in summer radiation, which resulted from long-term variations in the Earth's orbit around the Sun. The "Green Sahara" was dotted with numerous lakes, containing typical African lake crocodile and hippopotamus fauna. A curious discovery from the marine sediments is that the transitions into and out of the wet period occurred within decades, not the previously-thought extended periods.[39] It is hypothesized that humans played a role in altering the vegetation structure of North Africa at some point after 8,000 years ago by introducing domesticated animals, which contributed to the rapid transition to the arid conditions that are now found in many locations in the Sahara.[40] Further south, in Central Africa, the savannas that make up the coastal lowlands of the Congo River drainage basin in the present were entirely absent.[41] Southwestern Africa experienced increased humidity during the HCO.[42]

Northwestern Patagonia, in a region known as the Arid Diagonal, was significantly drier during the Early and Middle Holocene, with the region becoming more humid during the Late Holocene following the end of the HCO.[43]

In the far Southern Hemisphere (New Zealand and Antarctica), the warmest period during the Holocene appears to have been roughly 10,500 to 8,000 years ago, immediately after the end of the last ice age.[44][45] The Amery Ice Shelf retreated approximately 80 kilometres landward during this warm interval.[46] By 6,000 years ago, which is normally associated with the Holocene Climatic Optimum in the Northern Hemisphere, those regions had reached temperatures similar to today, and they did not participate in the temperature changes of the north. However, some authors have used the term "Holocene Climatic Optimum" to describe the earlier southern warm period as well; typically, the term "Early Holocene Climatic Optimum" is used for the Southern Hemisphere warm interval.[47][48]

In New Zealand, the HCO was associated with a 2 °C temperature gradient across the subtropical front (STF), a sharp contrast with the 6 °C observed today. Westerly winds in New Zealand were reduced.[49]

Comparison of ice cores

[edit]

A comparison of the delta profiles at Byrd Station, West Antarctica (2164 m ice core recovered, 1968), and Camp Century, Northwest Greenland, shows the post-glacial climatic optimum.[50] Points of correlation indicate that in both locations, the HCO (post-glacial climatic optimum) probably occurred at the same time. A similar comparison is evident between the Dye 3 1979 and the Camp Century 1963 cores regarding this period.[50]

The Hans Tausen Ice Cap, in Peary Land (northern Greenland), was drilled in 1977, with a new deep drill to 325 m. The ice core contained distinct melt layers all the way to the bedrock. That indicates that Hans Tausen Iskappe contains no ice from the last glaciation and so the world's northernmost ice cap melted away during the post-glacial climatic optimum and was rebuilt when the climate cooled some 4000 years ago.[50]

From the delta-profile, the Renland ice cap in the Scoresby Sound has always been separated from the inland ice, but all of the delta-leaps revealed in the Camp Century 1963 core recurred in the Renland 1985 ice core.[50] The Renland ice core from East Greenland apparently covers a full glacial cycle from the Holocene into the previous Eemian interglacial. The Renland ice core is 325 m long.[51]

Although the depths are different, the GRIP and NGRIP cores also contain the climatic optimum at very similar times.[50]

Milankovitch cycles

[edit]
Milankovitch cycles.

The climatic event was probably a result of predictable changes in the Earth's orbit (Milankovitch cycles) and a continuation of changes that caused the end of the last glacial period.[citation needed]

The effect would have had the maximum heating of the Northern Hemisphere 9,000 years ago, when the axial tilt was 24° and the nearest approach to the Sun (perihelion) was during the Northern Hemisphere's summer. The calculated Milankovitch Forcing would have provided 0.2% more solar radiation (+40 W/m2) to the Northern Hemisphere in summer, which tended to cause more heating. There seems to have been the predicted southward shift in the global band of thunderstorms, the Intertropical Convergence Zone.[citation needed]

However, orbital forcing would predict maximum climate response several thousand years earlier than those observed in the Northern Hemisphere. The delay may be a result of the continuing changes in climate, as the Earth emerged from the last glacial period and related to ice–albedo feedback. Different sites often show climate changes at somewhat different times and lasting for different durations. At some locations, climate changes may have begun as early as 11,000 years ago or have persisted until 4,000 years ago. As noted above, the warmest interval in the far south significantly preceded warming in the north.[citation needed]

Other changes

[edit]

Significant temperature changes do not appear to have occurred at most low-latitude sites, but other climate changes have been reported, such as significantly wetter conditions in Africa, Australia and Japan and desert-like conditions in the Midwestern United States. Areas around the Amazon show temperature increases and drier conditions.[52]

See also

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References

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  1. ^ Marcott, Shaun A.; Shakun, Jeremy D.; Clark, Peter U.; Mix, Alan C. (8 March 2013). "A Reconstruction of Regional and Global Temperature for the Past 11,300 Years". Science. 339 (6124): 1198–1201. Bibcode:2013Sci...339.1198M. doi:10.1126/science.1228026. PMID 23471405. S2CID 29665980. Archived from the original on 3 February 2023. Retrieved 13 March 2023.
  2. ^ Revkin, Andrew (22 April 2013). "Study Charts 2,000 Years of Continental Climate Change". New York Times Dot Earth. Archived from the original on 26 December 2021. Retrieved 26 December 2021.
  3. ^ Chandler, David (16 May 2007). "Climate myths: It's been far warmer in the past, what's the big deal?". New Scientist. Archived from the original on 26 December 2021. Retrieved 26 December 2021.
  4. ^ Neukom, R; Steiger, N; Gómez-Navarro, J.J (24 July 2019). "No evidence for globally coherent warm and cold periods over the preindustrial Common Era". Nature. 571 (7766): 550–554. Bibcode:2019Natur.571..550N. doi:10.1038/s41586-019-1401-2. PMID 31341300. S2CID 198494930. Archived from the original on 19 June 2024. Retrieved 26 December 2021.
  5. ^ Shakun, Jeremy D.; Carlson, Anders E. (1 July 2010). "A global perspective on Last Glacial Maximum to Holocene climate change". Quaternary Science Reviews. Special Theme: Arctic Palaeoclimate Synthesis (PP. 1674-1790). 29 (15): 1801–1816. doi:10.1016/j.quascirev.2010.03.016. ISSN 0277-3791. Archived from the original on 3 October 2023. Retrieved 17 September 2023.
  6. ^ Kaufman, Darrell; McKay, Nicholas; Routson, Cody; Erb, Michael; Dätwyler, Christoph; Sommer, Philipp S.; Heiri, Oliver; Davis, Basil (30 June 2022). "Holocene global mean surface temperature, a multi-method reconstruction approach". Scientific Data. 7 (1): 201. doi:10.1038/s41597-020-0530-7. PMC 7327079. PMID 32606396.
  7. ^ IPCC (2021). Masson-Delmotte, V.; Zhai, P.; Pirani, A.; Connors, S. L.; et al. (eds.). Climate Change 2021: The Physical Science Basis (PDF). Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press (In Press). p. SPM-9. Archived (PDF) from the original on 2021-08-13. Retrieved 2021-10-31.
  8. ^ Kitoh, Akio; Murakami, Shigenori (2002). "Tropical Pacific climate at the mid-Holocene and the Last Glacial Maximum". Paleoceanography and Paleoclimatology. 17 (3): 1047. Bibcode:2002PalOc..17.1047K. doi:10.1029/2001PA000724.
  9. ^ Gagan, Michael K.; Ayliffe, LK; Hopley, D; Cali, JA; Mortimer, GE; Chappell, J; McCulloch, MT; Head, MJ (1998). "Temperature and Surface-Ocean Water Balance of the Mid-Holocene Tropical Western Pacific". Science. 279 (5353): 1014–8. Bibcode:1998Sci...279.1014G. doi:10.1126/science.279.5353.1014. PMID 9461430. Archived from the original on 14 March 2023. Retrieved 13 March 2023.
  10. ^ Beierlein, Lars; Salvigsen, Otto; Schöne, Bernd R; Mackensen, Andreas; Brey, Thomas (16 April 2015). "The seasonal water temperature cycle in the Arctic Dicksonfjord (Svalbard) during the Holocene Climate Optimum derived from subfossil Arctica islandica shells". The Holocene. 25 (8): 1197–1207. doi:10.1177/0959683615580861. ISSN 0959-6836. S2CID 128781737. Archived from the original on 18 September 2023. Retrieved 8 September 2023.
  11. ^ D.S. Kaufman; T.A. Ager; N.J. Anderson; P.M. Anderson; J. T. Andrews; P. J. Bartlein; L. B. Brubaker; L.L. Coats; L. C. Cwynar; M. L. Duvall; A. S. Dyke; M.E. Edwards; W.R. Eisner; K. Gajewski; A. Geirsdottir; F.S. Hu; A.E. Jennings; M. R. Kaplan; M. W. Kerwin; A. V. Lozhkin; G.M. MacDonald; G.H. Miller; C.J. Mock; W. W. Oswald; B.L. Otto-Bliesner; D. F. Porinchu; K. Ruhland; J.P. Smol; E.J. Steig; B.B. Wolfe (2004). "Holocene thermal maximum in the western Arctic (0–180 W)" (PDF). Quaternary Science Reviews. 23 (5–6): 529–560. Bibcode:2004QSRv...23..529K. doi:10.1016/j.quascirev.2003.09.007. Archived (PDF) from the original on 2021-03-02. Retrieved 2019-12-14.
  12. ^ "NSIDC Arctic Sea Ice News". National Snow and Ice Data Center. Archived from the original on 28 April 2009. Retrieved 15 May 2009.
  13. ^ Vinther, B. M.; Buchardt, S. L.; Clausen, H. B.; Dahl-Jensen, D.; Johnsen, S. J.; Fisher, D. A.; Koerner, R. M.; Raynaud, D.; Lipenkov, V.; Andersen, K. K.; Blunier, T.; Rasmussen, S. O.; Steffensen, J. P.; Svensson, A. M. (17 September 2009). "Holocene thinning of the Greenland ice sheet". Nature. 461 (7262): 385–388. doi:10.1038/nature08355. ISSN 0028-0836. PMID 19759618. S2CID 4426637. Archived from the original on 4 February 2024. Retrieved 11 September 2023.
  14. ^ Davis, B.A.S.; Brewer, S.; Stevenson, A.C.; Guiot, J. (2003). "The temperature of Europe during the Holocene reconstructed from pollen data". Quaternary Science Reviews. 22 (15–17): 1701–16. Bibcode:2003QSRv...22.1701D. CiteSeerX 10.1.1.112.140. doi:10.1016/S0277-3791(03)00173-2.
  15. ^ Gomes, S. D.; Fletcher, W. J.; Rodrigues, T.; Stone, A.; Abrantes, F.; Naughton, F. (15 July 2020). "Time-transgressive Holocene maximum of temperate and Mediterranean forest development across the Iberian Peninsula reflects orbital forcing". Palaeogeography, Palaeoclimatology, Palaeoecology. 550: 109739. Bibcode:2020PPP...55009739G. doi:10.1016/j.palaeo.2020.109739. S2CID 216337848. Archived from the original on 6 November 2022. Retrieved 5 November 2022.
  16. ^ Zolitschka, Bernd; Behre, Karl-Ernst; Schneider, Jürgen (1 January 2003). "Human and climatic impact on the environment as derived from colluvial, fluvial and lacustrine archives—examples from the Bronze Age to the Migration period, Germany". Quaternary Science Reviews. Environmental response to climate and human impact in central Eur ope during the last 15000 years - a German contribution to PAGES-PEPIII. 22 (1): 81–100. doi:10.1016/S0277-3791(02)00182-8. ISSN 0277-3791. Archived from the original on 18 March 2012. Retrieved 11 September 2023.
  17. ^ Kalis, Arie J; Merkt, Josef; Wunderlich, Jürgen (1 January 2003). "Environmental changes during the Holocene climatic optimum in central Europe - human impact and natural causes". Quaternary Science Reviews. Environmental response to climate and human impact in central Eur ope during the last 15000 years - a German contribution to PAGES-PEPIII. 22 (1): 33–79. doi:10.1016/S0277-3791(02)00181-6. ISSN 0277-3791. Archived from the original on 8 March 2022. Retrieved 8 September 2023.
  18. ^ Rossignol-Strick, Martine (1 April 1999). "The Holocene climatic optimum and pollen records of sapropel 1 in the eastern Mediterranean, 9000–6000BP". Quaternary Science Reviews. 18 (4): 515–530. doi:10.1016/S0277-3791(98)00093-6. ISSN 0277-3791. Archived from the original on 19 June 2024. Retrieved 8 September 2023.
  19. ^ Maslennikova, A. V.; Udachin, V. N.; Aminov, P. G. (28 October 2016). "Lateglacial and Holocene environmental changes in the Southern Urals reflected in palynological, geochemical and diatom records from the Lake Syrytkul sediments". Quaternary International. The Quaternary of the Urals: Global trends and Pan-European Quaternary records. 420: 65–75. doi:10.1016/j.quaint.2015.08.062. ISSN 1040-6182. Archived from the original on 19 June 2024. Retrieved 8 September 2023.
  20. ^ Koshkarova, V.L.; Koshkarov, A.D. (2004). "Regional signatures of changing landscape and climate of northern central Siberia in the Holocene". Russian Geology and Geophysics. 45 (6): 672–685.[permanent dead link]
  21. ^ Gao, Fuyuan; Jia, Jia; Xia, Dunsheng; Lu, Caichen; Lu, Hao; Wang, Youjun; Liu, Hao; Ma, Yapeng; Li, Kaiming (15 March 2019). "Asynchronous Holocene Climate Optimum across mid-latitude Asia". Palaeogeography, Palaeoclimatology, Palaeoecology. 518: 206–214. doi:10.1016/j.palaeo.2019.01.012. S2CID 135199089. Archived from the original on 23 July 2023. Retrieved 5 September 2023.
  22. ^ Feng, Z.-D.; An, C. B.; Wang, H. B. (January 2006). "Holocene climatic and environmental changes in the arid and semi-arid areas of China: a review". The Holocene. 16 (1): 119–130. doi:10.1191/0959683606hl912xx. ISSN 0959-6836. Retrieved 21 July 2024 – via Sage Journals.
  23. ^ Yang, Shiling; Ding, Zhongli; Li, Yangyang; Wang, Xu; Jiang, Wengying; Huang, Xiaofang (12 October 2015). "Warming-induced northwestward migration of the East Asian monsoon rain belt from the Last Glacial Maximum to the mid-Holocene". Proceedings of the National Academy of Sciences of the United States of America. 112 (43): 13178–13183. Bibcode:2015PNAS..11213178Y. doi:10.1073/pnas.1504688112. PMC 4629344. PMID 26460029.
  24. ^ Wang, Wei; Liu, Lina; Li, Yanyan; Niu, Zhimei; He, Jiang; Ma, Yuzhen; Mensing, Scott A. (15 August 2019). "Pollen reconstruction and vegetation dynamics of the middle Holocene maximum summer monsoon in northern China". Palaeogeography, Palaeoclimatology, Palaeoecology. 528: 204–217. Bibcode:2019PPP...528..204W. doi:10.1016/j.palaeo.2019.05.023. S2CID 182641708. Archived from the original on 6 December 2022. Retrieved 6 December 2022.
  25. ^ An, Zhisheng; Porter, Stephen C.; Kutzbach, John E.; Xihao, Wu; Suming, Wang; Xiaodong, Liu; Xiaoqiang, Li; Weijian, Zhou (April 2000). "Asynchronous Holocene optimum of the East Asian monsoon". Quaternary Science Reviews. 19 (8): 743–762. Bibcode:2000QSRv...19..743A. doi:10.1016/S0277-3791(99)00031-1. Archived from the original on 10 July 2023. Retrieved 9 July 2023.
  26. ^ Zhang, Jingwei; Kong, Xinggong; Zhao, Kan; Wang, Yongjin; Liu, Shushuang; Wang, Zhenjun; Liu, Jianwei; Cheng, Hai; Edwards, R. Lawrence (15 November 2020). "Centennial-scale climatic changes in Central China during the Holocene climatic optimum". Palaeogeography, Palaeoclimatology, Palaeoecology. 558: 109950. doi:10.1016/j.palaeo.2020.109950. Retrieved 21 July 2024 – via Elsevier Science Direct.
  27. ^ "Eurasia During the Last 150,000 Years". Archived from the original on 8 June 2012. Retrieved 7 June 2012.
  28. ^ Hudson, Adam M.; Olsen, John W.; Quade, Jay; Lei, Guoliang; Huth, Tyler; Zhang, Hucai (May 2016). "A regional record of expanded Holocene wetlands and prehistoric human occupation from paleowetland deposits of the western Yarlung Tsangpo valley, southern Tibetan Plateau". Quaternary Research. 86 (1): 13–33. Bibcode:2016QuRes..86...13H. doi:10.1016/j.yqres.2016.04.001. Archived from the original on 19 June 2024. Retrieved 22 April 2023.
  29. ^ Jiang, Shiwei; Luo, Wuhong; Tu, Luyao; Yu, Yanyan; Fang, Fang; Liu, Xiaoyan; Zhan, Tao; Fang, Lidong; Zhang, Xiaolin; Zhou, Xin (14 August 2018). "The Holocene optimum (HO) and the response of human activity: A case study of the Huai River Basin in eastern China". Quaternary International. 493: 31–38. doi:10.1016/j.quaint.2018.08.011. Retrieved 21 July 2024 – via Elsevier Science Direct.
  30. ^ Qiu, Zhenwei; Jiang, Hongen; Ding, Lanlan; Shang, Xue (9 June 2020). "Late Pleistocene-Holocene vegetation history and anthropogenic activities deduced from pollen spectra and archaeological data at Guxu Lake, eastern China". Scientific Reports. 10 (1): 9306. Bibcode:2020NatSR..10.9306Q. doi:10.1038/s41598-020-65834-z. PMC 7283361. PMID 32518244.
  31. ^ Zhang, Zhiping; Liu, Jianbao; Chen, Jie; Chen, Shengqian; Shen, Zhongwei; Chen, Jie; Liu, Xiaokang; Wu, Duo; Sheng, Yongwei; Chen, Fahu (January 2021). "Holocene climatic optimum in the East Asian monsoon region of China defined by climatic stability". Earth-Science Reviews. 212: 103450. doi:10.1016/j.earscirev.2020.103450. S2CID 229436491. Archived from the original on 27 October 2022. Retrieved 5 September 2023.
  32. ^ Park, Jungjae; Park, Jinheum; Yi, Sangheon; Kim, Jin Cheul; Lee, Eunmi; Choi, Jieun (25 July 2019). "Abrupt Holocene climate shifts in coastal East Asia, including the 8.2 ka, 4.2 ka, and 2.8 ka BP events, and societal responses on the Korean peninsula". Scientific Reports. 9 (1): 10806. Bibcode:2019NatSR...910806P. doi:10.1038/s41598-019-47264-8. PMC 6658530. PMID 31346228.
  33. ^ Evstigneeva, T. A.; Naryshkina, N. N. (8 January 2011). "The Holocene climatic optimum at the southern coast of the Sea of Japan". Paleontological Journal. 44 (10): 1262–1269. doi:10.1134/S0031030110100047. S2CID 59574305. Archived from the original on 29 January 2023. Retrieved 28 January 2023.
  34. ^ Yu, Ke-Fu; Zhao, Jian-Xin; Liu, Tung-Sheng; Wei, Gang-Jian; Wang, Pin-Xian; Collerson, Kenneth D (30 July 2004). "High-frequency winter cooling and reef coral mortality during the Holocene climatic optimum". Earth and Planetary Science Letters. 224 (1–2): 143–155. doi:10.1016/j.epsl.2004.04.036. Archived from the original on 18 May 2023. Retrieved 8 September 2023.
  35. ^ Shaji, Jithu; Banerji, Upasana S.; Maya, K.; Joshi, Kumar Batuk; Dabhi, Ankur J.; Bharti, Nisha; Bhushan, Ravi; Padmalal, D. (30 December 2022). "Holocene monsoon and sea-level variability from coastal lowlands of Kerala, SW India". Quaternary International. Shifting Quaternary Climate over Indian sub-Continent. 642: 48–62. doi:10.1016/j.quaint.2022.03.005. ISSN 1040-6182. S2CID 247553867. Archived from the original on 19 June 2024. Retrieved 11 September 2023.
  36. ^ Mann, Thomas; Rovere, Alessio; Schöne, Tilo; Klicpera, André; Stocchi, Paolo; Lukman, Muhammad; Westphal, Hildegard (15 March 2016). "The magnitude of a mid-Holocene sea-level highstand in the Strait of Makassar". Geomorphology. 257: 155–163. Bibcode:2016Geomo.257..155M. doi:10.1016/j.geomorph.2015.12.023. Archived from the original on 22 April 2023. Retrieved 21 April 2023.
  37. ^ Bender, Maren; Mann, Thomas; Stocchi, Paolo; Kneer, Dominik; Schöne, Tilo; Illigner, Julia; Jompa, Jamaluddin; Rovere, Alessio (2020). "Late Holocene (0–6 ka) sea-level changes in the Makassar Strait, Indonesia". Climate of the Past. 16 (4): 1187–1205. Bibcode:2020CliPa..16.1187B. doi:10.5194/cp-16-1187-2020. S2CID 221681240. Archived from the original on 27 April 2023. Retrieved 21 April 2023.
  38. ^ Kappelmann, Yannis; Westphal, Hildegard; Kneer, Dominik; Wu, Henry C.; Wizemann, André; Jompa, Jamaluddin; Mann, Thomas (28 March 2023). "Fluctuating sea-level and reversing Monsoon winds drive Holocene lagoon infill in Southeast Asia". Scientific Reports. 13 (1): 5042. Bibcode:2023NatSR..13.5042K. doi:10.1038/s41598-023-31976-z. PMC 10050433. PMID 36977704. Archived from the original on 19 June 2024. Retrieved 12 July 2023.
  39. ^ "Abrupt Climate Changes Revisited: How Serious and How Likely?". USGCRP Seminar, 23 February 1998. Archived from the original on 11 June 2007. Retrieved May 18, 2005.
  40. ^ Wright, David K. (26 January 2017). "Humans as Agents in the Termination of the African Humid Period". Frontiers in Earth Science. 5: 4. Bibcode:2017FrEaS...5....4W. doi:10.3389/feart.2017.00004.
  41. ^ Jansen, J. H. F.; Van Weering, T. C. E.; Gieles, R.; Van Iperen, J. (1 October 1984). "Middle and late quaternary oceanography and climatology of the Zaire-Congo fan and the adjacent Eastern Angola basin". Netherlands Journal of Sea Research. 17 (2): 201–249. doi:10.1016/0077-7579(84)90048-6. ISSN 0077-7579. Archived from the original on 19 June 2024. Retrieved 17 September 2023.
  42. ^ Gingele, Franz X. (June 1996). "Holocene climatic optimum in Southwest Africa—evidence from the marine clay mineral record". Palaeogeography, Palaeoclimatology, Palaeoecology. 122 (1–4): 77–87. doi:10.1016/0031-0182(96)00076-4. Archived from the original on 14 April 2024. Retrieved 8 September 2023.
  43. ^ Llano, Carina; De Porras, María Eugenia; Barberena, Ramiro; Timpson, Adrian; Beltrame, M. Ornela; Marsh, Erik J. (1 November 2020). "Human resilience to Holocene climate changes inferred from rodent middens in drylands of northwestern Patagonia (Argentina)". Palaeogeography, Palaeoclimatology, Palaeoecology. 557: 109894. Bibcode:2020PPP...55709894L. doi:10.1016/j.palaeo.2020.109894. S2CID 221881153. Archived from the original on 6 December 2022. Retrieved 6 December 2022.
  44. ^ Masson, V.; Vimeux, F.; Jouzel, J.; Morgan, V.; Delmotte, M.; Ciais,P.; Hammer, C.; Johnsen, S.; Lipenkov, V.Y.; Mosley-Thompson, E.; Petit, J.-R.; Steig, E.J.; Stievenard, M.; Vaikmae, R. (November 2000). "Holocene climate variability in Antarctica based on 11 ice-core isotopic records". Quaternary Research. 54 (3): 348–358. Bibcode:2000QuRes..54..348M. doi:10.1006/qres.2000.2172. S2CID 129887335. Archived from the original on 22 June 2023. Retrieved 21 June 2023.
  45. ^ P.W. Williams; D.N.T. King; J.-X. Zhao K.D. Collerson (2004). "Speleothem master chronologies: combined Holocene 18O and 13C records from the North Island of New Zealand and their paleoenvironmental interpretation". The Holocene. 14 (2): 194–208. Bibcode:2004Holoc..14..194W. doi:10.1191/0959683604hl676rp. S2CID 131290609.
  46. ^ Hemer, Mark A.; Harris, Peter T. (1 February 2003). "Sediment core from beneath the Amery Ice Shelf, East Antarctica, suggests mid-Holocene ice-shelf retreat". Geology. 31 (2): 127–130. Bibcode:2003Geo....31..127H. doi:10.1130/0091-7613(2003)031<0127:SCFBTA>2.0.CO;2. Archived from the original on 27 January 2023. Retrieved 26 January 2023.
  47. ^ Ciais, P; Petit, J R; Jouzel, J; Lorius, C; Barkov, N I; Lipenkov, V; Nicolaïev, V (January 1992). "Evidence for an early Holocene climatic optimum in the Antarctic deep ice-core record". Climate Dynamics. 6 (3–4): 169–177. doi:10.1007/BF00193529. ISSN 0930-7575. S2CID 128416497. Retrieved 5 September 2023.
  48. ^ Bostock, H. C.; Prebble, J. G.; Cortese, G.; Hayward, B.; Calvo, E.; Quirós-Collazos, L.; Kienast, M.; Kim, K. (31 March 2019). "Paleoproductivity in the SW Pacific Ocean During the Early Holocene Climatic Optimum". Paleoceanography and Paleoclimatology. 34 (4): 580–599. doi:10.1029/2019PA003574. hdl:10261/181776. ISSN 2572-4517. S2CID 135452816. Archived from the original on 19 June 2024. Retrieved 5 September 2023.
  49. ^ Prebble, J. G.; Bostock, H. C.; Cortese, G.; Lorrey, A. M.; Hayward, B. W.; Calvo, E.; Northcote, L. C.; Scott, G. H.; Neil, H. L. (August 2017). "Evidence for a Holocene Climatic Optimum in the southwest Pacific: A multiproxy study: Holocene Optimum in SW Pacific". Paleoceanography and Paleoclimatology. 32 (8): 763–779. doi:10.1002/2016PA003065. hdl:10261/155815. Archived from the original on 19 June 2024. Retrieved 8 September 2023.
  50. ^ a b c d e Dansgaard W (2004). Frozen Annals Greenland Ice Sheet Research. Odder, Denmark: Narayana Press. p. 124. ISBN 978-87-990078-0-6.
  51. ^ Hansson M, Holmén K (15 November 2001). "High latitude biospheric activity during the Last Glacial Cycle revealed by ammonium variations in Greenland Ice Cores". Geophysical Research Letters. 28 (22): 4239–42. Bibcode:2001GeoRL..28.4239H. doi:10.1029/2000GL012317. S2CID 140677584.
  52. ^ Francis E. Mayle, David J. Beerling, William D. Gosling, Mark B. Bush (2004). "Responses of Amazonian ecosystems to climatic and atmospheric carbon dioxide changes since the Last Glacial Maximum". Philosophical Transactions: Biological Sciences. 359 (1443): 499–514. doi:10.1098/rstb.2003.1434. PMC 1693334. PMID 15212099.{{cite journal}}: CS1 maint: multiple names: authors list (link)