Antarctic Cold Reversal
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The Antarctic Cold Reversal (ACR) was a climatic event of intense atmospheric and oceanic cooling across the southern hemisphere (>40°S) between 14,700 and 13,000 years before present (BP) that interrupted the most recent deglacial climate warming (c. 18,000-11,500 years BP).[1][2] This cooling event was initially well noted in Antarctic ice core records.[2][3][4][5] Soon after, evidence from sediment cores and glacial advances from land masses (southern South America,[6][7][8][9][10][11][12] New Zealand,[13][14][15][16] Tasmania,[17][18] among others[19]) and Oceanic sectors[20] south of 40°S expanded the region of this climate cooling event. The ACR illustrates the complexity of the climate changes at the transition from the Pleistocene to the Holocene Epochs.[1]
In general, climate models show a 1.5-2 °C[1] drop in Antarctica and other temperate regions where glacial readvances[7][12][13] are typically evident. Climate continued to warm after 13,000 years BP and glaciers showed signs of abrupt withdrawal from their respective ACR aged moraines. The mechanisms behind the atmospheric and oceanic reorganization are still debated, although strengthening of the Atlantic Meridional Overturnig Circulation is alluded to in general.[1][5]
Stratigraphic and Glacial evidences
[edit]Global climate during the last Ice Age reached its coolest temperatures between c. 21,000 and 18,000 years BP, marking the onset of the last glacial termination. This transition out of the last Ice Age, also known as deglaciation, lasted until c. 11,500 years BP, when temperature, atmospheric CO2 concentrations, and sea level ceased to increase as rapidly, and glaciers reached their less extensive Holocene positions. The period bracketed as the ACR (14,700-13,000 years BP) is characterized by a reversal or halt in these deglacial trends, i.e., temperatures cooled, atmospheric CO2 concentrations halted, and glaciers readvanced. Climatic, geologic, and ecologic changes during the ACR are nuanced among geographical regions that showed signs of cooling.
Antarctica
[edit]The ACR is characterized in Antarctica through the ice cores retrieved from locations spread across the whole continent.[21][22][23][24] The principal proxy that tracks atmospheric cooling in Antarctic ice cores are the deuterium signatures which show negative deviations between 14,000 and 12,500 years BP. CO2 concentrations have also been shown to consistently drop during this period in these ice cores.
South America
[edit]Southern South America has well conserved evidences of climatic cooling during the ACR. Stratigraphic records from southern Patagonia (45°-54°S) show ecological changes associated with climatic cooling or increased precipitation.[25][26][27][28][29][30][31] For example, pollen records show cold tolerant and alpine vegetation that shifted to Rain forest vegetation after 12,500 years BP.
New Zealand
[edit]New Zealand features a swath of records that show a millennial-scale climate cooling during the ACR. Stratigraphic records from the Southern Alps track glacier advances and pronounced forest changes between 14,500 and 12,800 years BP.[32][33][34] Chironomid-inferred temperature records suggest a summer temperature decrease of ~3-2 °C.[33]
Tasmania
[edit]Paleoclimatic records from Tasmania have bracketed a local climate cooling event between 14,900 and 12,800 years BP, coincident with the ACR.[35][36] A paucity in local fire events and an increase in cold-tolerant Rainforest taxa attest to this climatic cooling in Tasmania.
References
[edit]- ^ a b c d Pedro, Joel B.; Bostock, Helen C.; Bitz, Cecilia M.; He, Feng; Vandergoes, Marcus J.; Steig, Eric J.; Chase, Brian M.; Krause, Claire E.; Rasmussen, Sune O.; Markle, Bradley R.; Cortese, Giuseppe (January 2016). "The spatial extent and dynamics of the Antarctic Cold Reversal". Nature Geoscience. 9 (1): 51–55. Bibcode:2016NatGe...9...51P. doi:10.1038/ngeo2580. ISSN 1752-0894.
- ^ a b Pedro, J. B.; van Ommen, T. D.; Rasmussen, S. O.; Morgan, V. I.; Chappellaz, J.; Moy, A. D.; Masson-Delmotte, V.; Delmotte, M. (2011-06-24). "The last deglaciation: timing the bipolar seesaw". Climate of the Past. 7 (2): 671–683. Bibcode:2011CliPa...7..671P. doi:10.5194/cp-7-671-2011. ISSN 1814-9332.
- ^ Jouzel, J.; Masson, V.; Cattani, O.; Falourd, S.; Stievenard, M.; Stenni, B.; Longinelli, A.; Johnsen, S. J.; Steffenssen, J. P.; Petit, J. R.; Schwander, J.; Souchez, R.; Barkov, N. I. (2001-08-15). "A new 27 ky high resolution East Antarctic climate record". Geophysical Research Letters. 28 (16): 3199–3202. Bibcode:2001GeoRL..28.3199J. doi:10.1029/2000GL012243. ISSN 0094-8276.
- ^ Jouzel, J; Vaikmae, R; Petit, J R; Martin, M; Duclos, Y; Stievenard, M; Lorius, C; Toots, M; Mélières, M A; Burckle, L H; Barkov, N I; Kotlyakov, V M (April 1995). "The two-step shape and timing of the last deglaciation in Antarctica". Climate Dynamics. 11 (3): 151–161. Bibcode:1995ClDy...11..151J. doi:10.1007/BF00223498. ISSN 0930-7575.
- ^ a b Stenni, Barbara; Masson-Delmotte, Valerie; Johnsen, Sigfus; Jouzel, Jean; Longinelli, Antonio; Monnin, Eric; Röthlisberger, Regine; Selmo, Enrico (2001-09-14). "An Oceanic Cold Reversal During the Last Deglaciation". Science. 293 (5537): 2074–2077. Bibcode:2001Sci...293.2074S. doi:10.1126/science.1059702. ISSN 0036-8075. PMID 11557889.
- ^ Mendelová, Monika; Hein, Andrew S.; Rodés, Ángel; Smedley, Rachel K.; Xu, Sheng (January 2020). "Glacier expansion in central Patagonia during the Antarctic Cold Reversal followed by retreat and stabilisation during the Younger Dryas". Quaternary Science Reviews. 227: 106047. Bibcode:2020QSRv..22706047M. doi:10.1016/j.quascirev.2019.106047.
- ^ a b Sagredo, Esteban A.; Kaplan, Michael R.; Araya, Paola S.; Lowell, Thomas V.; Aravena, Juan C.; Moreno, Patricio I.; Kelly, Meredith A.; Schaefer, Joerg M. (May 2018). "Trans-pacific glacial response to the Antarctic Cold Reversal in the southern mid-latitudes". Quaternary Science Reviews. 188: 160–166. Bibcode:2018QSRv..188..160S. doi:10.1016/j.quascirev.2018.01.011.
- ^ Moreno, P.I.; Kaplan, M.R.; François, J.P.; Villa-Martínez, R.; Moy, C.M.; Stern, C.R.; Kubik, P.W. (April 2009). "Renewed glacial activity during the Antarctic cold reversal and persistence of cold conditions until 11.5 ka in southwestern Patagonia". Geology. 37 (4): 375–378. Bibcode:2009Geo....37..375M. doi:10.1130/G25399A.1. ISSN 1943-2682.
- ^ García, Juan L.; Kaplan, Michael R.; Hall, Brenda L.; Schaefer, Joerg M.; Vega, Rodrigo M.; Schwartz, Roseanne; Finkel, Robert (September 2012). "Glacier expansion in southern Patagonia throughout the Antarctic cold reversal". Geology. 40 (9): 859–862. Bibcode:2012Geo....40..859G. doi:10.1130/G33164.1. ISSN 1943-2682.
- ^ Moreno, P.I.; Fercovic, E.I.; Soteres, R.L.; Ugalde, P.I.; Sagredo, E.A.; Villa-Martínez, R.P. (December 2022). "Glacier and terrestrial ecosystem evolution in the Chilotan archipelago sector of northwestern Patagonia since the Last Glacial Termination". Earth-Science Reviews. 235: 104240. Bibcode:2022ESRv..23504240M. doi:10.1016/j.earscirev.2022.104240.
- ^ Reynhout, Scott A.; Kaplan, Michael R.; Sagredo, Esteban A.; Aravena, Juan Carlos; Soteres, Rodrigo L.; Schwartz, Roseanne; Schaefer, Joerg M. (January 2022). "Holocene glacier history of northeastern Cordillera Darwin, southernmost South America (55°S)". Quaternary Research. 105: 166–181. Bibcode:2022QuRes.105..166R. doi:10.1017/qua.2021.45. ISSN 0033-5894.
- ^ a b Soteres, Rodrigo L.; Sagredo, Esteban A.; Kaplan, Michael R.; Martini, Mateo A.; Moreno, Patricio I.; Reynhout, Scott A.; Schwartz, Roseanne; Schaefer, Joerg M. (2022-06-27). "Glacier fluctuations in the northern Patagonian Andes (44°S) imply wind-modulated interhemispheric in-phase climate shifts during Termination 1". Scientific Reports. 12 (1): 10842. Bibcode:2022NatSR..1210842S. doi:10.1038/s41598-022-14921-4. ISSN 2045-2322. PMC 9237032. PMID 35761034.
- ^ a b Putnam, Aaron E.; Denton, George H.; Schaefer, Joerg M.; Barrell, David J. A.; Andersen, Bjørn G.; Finkel, Robert C.; Schwartz, Roseanne; Doughty, Alice M.; Kaplan, Michael R.; Schlüchter, Christian (October 2010). "Glacier advance in southern middle-latitudes during the Antarctic Cold Reversal". Nature Geoscience. 3 (10): 700–704. Bibcode:2010NatGe...3..700P. doi:10.1038/ngeo962. ISSN 1752-0894.
- ^ Tielidze, Levan G.; Eaves, Shaun R.; Norton, Kevin P.; Mackintosh, Andrew N.; Pedro, Joel B.; Hidy, Alan J. (May 2023). "Early glacier advance in New Zealand during the Antarctic Cold Reversal". Journal of Quaternary Science. 38 (4): 544–562. Bibcode:2023JQS....38..544T. doi:10.1002/jqs.3495. ISSN 0267-8179.
- ^ Vandergoes, Marcus J.; Dieffenbacher-Krall, Ann C.; Newnham, Rewi M.; Denton, George H.; Blaauw, Maarten (March 2008). "Cooling and changing seasonality in the Southern Alps, New Zealand during the Antarctic Cold Reversal". Quaternary Science Reviews. 27 (5–6): 589–601. Bibcode:2008QSRv...27..589V. doi:10.1016/j.quascirev.2007.11.015.
- ^ Hajdas, Irka; Lowe, David J.; Newnham, Rewi M.; Bonani, Georges (March 2006). "Timing of the late-glacial climate reversal in the Southern Hemisphere using high-resolution radiocarbon chronology for Kaipo Bog, New Zealand". Quaternary Research. 65 (2): 340–345. Bibcode:2006QuRes..65..340H. doi:10.1016/j.yqres.2005.08.028. ISSN 0033-5894.
- ^ Fletcher, Michael-Shawn; Pedro, Joel; Hall, Tegan; Mariani, Michela; Alexander, Joseph A.; Beck, Kristen; Blaauw, Maarten; Hodgson, Dominic A.; Heijnis, Henk; Gadd, Patricia S.; Lise-Pronovost, Agathe (November 2021). "Northward shift of the southern westerlies during the Antarctic Cold Reversal". Quaternary Science Reviews. 271: 107189. Bibcode:2021QSRv..27107189F. doi:10.1016/j.quascirev.2021.107189.
- ^ Henríquez, William I.; Fletcher, Michael-Shawn; Romano, Anthony (October 2023). "Vegetation, fire and climate history in central-western Tasmania (41°S), Australia, over the last ∼21,000 years". Quaternary Science Reviews. 318: 108315. Bibcode:2023QSRv..31808315H. doi:10.1016/j.quascirev.2023.108315.
- ^ Graham, Alastair G. C.; Kuhn, Gerhard; Meisel, Ove; Hillenbrand, Claus-Dieter; Hodgson, Dominic A.; Ehrmann, Werner; Wacker, Lukas; Wintersteller, Paul; dos Santos Ferreira, Christian; Römer, Miriam; White, Duanne; Bohrmann, Gerhard (2017-03-17). "Major advance of South Georgia glaciers during the Antarctic Cold Reversal following extensive sub-Antarctic glaciation". Nature Communications. 8 (1): 14798. Bibcode:2017NatCo...814798G. doi:10.1038/ncomms14798. ISSN 2041-1723. PMC 5357866. PMID 28303885.
- ^ Fogwill, C. J.; Turney, C. S. M.; Menviel, L.; Baker, A.; Weber, M. E.; Ellis, B.; Thomas, Z. A.; Golledge, N. R.; Etheridge, D.; Rubino, M.; Thornton, D. P.; van Ommen, T. D.; Moy, A. D.; Curran, M. A. J.; Davies, S. (July 2020). "Southern Ocean carbon sink enhanced by sea-ice feedbacks at the Antarctic Cold Reversal". Nature Geoscience. 13 (7): 489–497. Bibcode:2020NatGe..13..489F. doi:10.1038/s41561-020-0587-0. ISSN 1752-0894.
- ^ Pedro, J. B.; van Ommen, T. D.; Rasmussen, S. O.; Morgan, V. I.; Chappellaz, J.; Moy, A. D.; Masson-Delmotte, V.; Delmotte, M. (2011-06-24). "The last deglaciation: timing the bipolar seesaw". Climate of the Past. 7 (2): 671–683. Bibcode:2011CliPa...7..671P. doi:10.5194/cp-7-671-2011. ISSN 1814-9332.
- ^ Jouzel, J.; Masson, V.; Cattani, O.; Falourd, S.; Stievenard, M.; Stenni, B.; Longinelli, A.; Johnsen, S. J.; Steffenssen, J. P.; Petit, J. R.; Schwander, J.; Souchez, R.; Barkov, N. I. (2001-08-15). "A new 27 ky high resolution East Antarctic climate record". Geophysical Research Letters. 28 (16): 3199–3202. Bibcode:2001GeoRL..28.3199J. doi:10.1029/2000GL012243. ISSN 0094-8276.
- ^ Jouzel, J; Vaikmae, R; Petit, J R; Martin, M; Duclos, Y; Stievenard, M; Lorius, C; Toots, M; Mélières, M A; Burckle, L H; Barkov, N I; Kotlyakov, V M (April 1995). "The two-step shape and timing of the last deglaciation in Antarctica". Climate Dynamics. 11 (3): 151–161. Bibcode:1995ClDy...11..151J. doi:10.1007/BF00223498. ISSN 0930-7575.
- ^ Stenni, Barbara; Masson-Delmotte, Valerie; Johnsen, Sigfus; Jouzel, Jean; Longinelli, Antonio; Monnin, Eric; Röthlisberger, Regine; Selmo, Enrico (2001-09-14). "An Oceanic Cold Reversal During the Last Deglaciation". Science. 293 (5537): 2074–2077. Bibcode:2001Sci...293.2074S. doi:10.1126/science.1059702. ISSN 0036-8075. PMID 11557889.
- ^ Mendelová, Monika; Hein, Andrew S.; Rodés, Ángel; Smedley, Rachel K.; Xu, Sheng (January 2020). "Glacier expansion in central Patagonia during the Antarctic Cold Reversal followed by retreat and stabilisation during the Younger Dryas". Quaternary Science Reviews. 227: 106047. Bibcode:2020QSRv..22706047M. doi:10.1016/j.quascirev.2019.106047.
- ^ Sagredo, Esteban A.; Kaplan, Michael R.; Araya, Paola S.; Lowell, Thomas V.; Aravena, Juan C.; Moreno, Patricio I.; Kelly, Meredith A.; Schaefer, Joerg M. (May 2018). "Trans-pacific glacial response to the Antarctic Cold Reversal in the southern mid-latitudes". Quaternary Science Reviews. 188: 160–166. Bibcode:2018QSRv..188..160S. doi:10.1016/j.quascirev.2018.01.011.
- ^ Moreno, P.I.; Kaplan, M.R.; François, J.P.; Villa-Martínez, R.; Moy, C.M.; Stern, C.R.; Kubik, P.W. (April 2009). "Renewed glacial activity during the Antarctic cold reversal and persistence of cold conditions until 11.5 ka in southwestern Patagonia". Geology. 37 (4): 375–378. Bibcode:2009Geo....37..375M. doi:10.1130/G25399A.1. ISSN 1943-2682.
- ^ García, Juan L.; Kaplan, Michael R.; Hall, Brenda L.; Schaefer, Joerg M.; Vega, Rodrigo M.; Schwartz, Roseanne; Finkel, Robert (September 2012). "Glacier expansion in southern Patagonia throughout the Antarctic cold reversal". Geology. 40 (9): 859–862. Bibcode:2012Geo....40..859G. doi:10.1130/G33164.1. ISSN 1943-2682.
- ^ Moreno, P.I.; Fercovic, E.I.; Soteres, R.L.; Ugalde, P.I.; Sagredo, E.A.; Villa-Martínez, R.P. (December 2022). "Glacier and terrestrial ecosystem evolution in the Chilotan archipelago sector of northwestern Patagonia since the Last Glacial Termination". Earth-Science Reviews. 235: 104240. Bibcode:2022ESRv..23504240M. doi:10.1016/j.earscirev.2022.104240.
- ^ Reynhout, Scott A.; Kaplan, Michael R.; Sagredo, Esteban A.; Aravena, Juan Carlos; Soteres, Rodrigo L.; Schwartz, Roseanne; Schaefer, Joerg M. (January 2022). "Holocene glacier history of northeastern Cordillera Darwin, southernmost South America (55°S)". Quaternary Research. 105: 166–181. Bibcode:2022QuRes.105..166R. doi:10.1017/qua.2021.45. ISSN 0033-5894.
- ^ Soteres, Rodrigo L.; Sagredo, Esteban A.; Kaplan, Michael R.; Martini, Mateo A.; Moreno, Patricio I.; Reynhout, Scott A.; Schwartz, Roseanne; Schaefer, Joerg M. (2022-06-27). "Glacier fluctuations in the northern Patagonian Andes (44°S) imply wind-modulated interhemispheric in-phase climate shifts during Termination 1". Scientific Reports. 12 (1): 10842. Bibcode:2022NatSR..1210842S. doi:10.1038/s41598-022-14921-4. ISSN 2045-2322. PMC 9237032. PMID 35761034.
- ^ Putnam, Aaron E.; Denton, George H.; Schaefer, Joerg M.; Barrell, David J. A.; Andersen, Bjørn G.; Finkel, Robert C.; Schwartz, Roseanne; Doughty, Alice M.; Kaplan, Michael R.; Schlüchter, Christian (October 2010). "Glacier advance in southern middle-latitudes during the Antarctic Cold Reversal". Nature Geoscience. 3 (10): 700–704. Bibcode:2010NatGe...3..700P. doi:10.1038/ngeo962. ISSN 1752-0894.
- ^ a b Vandergoes, Marcus J.; Dieffenbacher-Krall, Ann C.; Newnham, Rewi M.; Denton, George H.; Blaauw, Maarten (March 2008). "Cooling and changing seasonality in the Southern Alps, New Zealand during the Antarctic Cold Reversal". Quaternary Science Reviews. 27 (5–6): 589–601. Bibcode:2008QSRv...27..589V. doi:10.1016/j.quascirev.2007.11.015.
- ^ Hajdas, Irka; Lowe, David J.; Newnham, Rewi M.; Bonani, Georges (March 2006). "Timing of the late-glacial climate reversal in the Southern Hemisphere using high-resolution radiocarbon chronology for Kaipo Bog, New Zealand". Quaternary Research. 65 (2): 340–345. Bibcode:2006QuRes..65..340H. doi:10.1016/j.yqres.2005.08.028. ISSN 0033-5894.
- ^ Henríquez, William I.; Fletcher, Michael-Shawn; Romano, Anthony (October 2023). "Vegetation, fire and climate history in central-western Tasmania (41°S), Australia, over the last ∼21,000 years". Quaternary Science Reviews. 318: 108315. Bibcode:2023QSRv..31808315H. doi:10.1016/j.quascirev.2023.108315.
- ^ Fletcher, Michael-Shawn; Pedro, Joel; Hall, Tegan; Mariani, Michela; Alexander, Joseph A.; Beck, Kristen; Blaauw, Maarten; Hodgson, Dominic A.; Heijnis, Henk; Gadd, Patricia S.; Lise-Pronovost, Agathe (November 2021). "Northward shift of the southern westerlies during the Antarctic Cold Reversal". Quaternary Science Reviews. 271: 107189. Bibcode:2021QSRv..27107189F. doi:10.1016/j.quascirev.2021.107189.