Modeling geologically abrupt climate changes in the Miocene: Potential effects of high-latitudinal salinity changes
Affiliation(s)
EMS Earth and Environmental Systems Institute, Pennsylvania State University, University Park, USA. NOAA/National Oceanographic Data Center, Silver Spring, USA.
EMS Earth and Environmental Systems Institute, Pennsylvania State University, University Park, USA. NOAA/National Oceanographic Data Center, Silver Spring, USA.
ABSTRACT
The cooling of the Cenozoic, including the Miocene epoch, was punctuated by many geologically abrupt warming and cooling episodes— strong deviations from the cooling trend with time span of ten to hundred thousands of years. Our working hypothesis is that some of those warming episodes at least partially might have been caused by dynamics of the Antarctic Ice Sheet, which, in turn, might have caused strong changes of sea surface salinity in the Miocene Southern Ocean. Feasibility of this hypothesis is explored in a series of offline-coupled ocean-atmosphere computer experiments. The results suggest that relatively small and geologically short-lived changes in freshwater balance in the Southern Ocean could have significantly contributed to at least two prominent warming episodes in the Miocene. Importantly, the scenario-based experiments also suggest that the Southern Ocean was more sensitive to the salinity changes in the Miocene than today, which can attributed to the opening of the Central American Isthmus as a major difference between the Miocene and the present-day ocean-sea geometry.
The cooling of the Cenozoic, including the Miocene epoch, was punctuated by many geologically abrupt warming and cooling episodes— strong deviations from the cooling trend with time span of ten to hundred thousands of years. Our working hypothesis is that some of those warming episodes at least partially might have been caused by dynamics of the Antarctic Ice Sheet, which, in turn, might have caused strong changes of sea surface salinity in the Miocene Southern Ocean. Feasibility of this hypothesis is explored in a series of offline-coupled ocean-atmosphere computer experiments. The results suggest that relatively small and geologically short-lived changes in freshwater balance in the Southern Ocean could have significantly contributed to at least two prominent warming episodes in the Miocene. Importantly, the scenario-based experiments also suggest that the Southern Ocean was more sensitive to the salinity changes in the Miocene than today, which can attributed to the opening of the Central American Isthmus as a major difference between the Miocene and the present-day ocean-sea geometry.
Cite this paper
Haupt, B. and Seidov, D. (2012) Modeling geologically abrupt climate changes in the Miocene: Potential effects of high-latitudinal salinity changes. Natural Science, 4, 149-158. doi: 10.4236/ns.2012.43022.
Haupt, B. and Seidov, D. (2012) Modeling geologically abrupt climate changes in the Miocene: Potential effects of high-latitudinal salinity changes. Natural Science, 4, 149-158. doi: 10.4236/ns.2012.43022.
References
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[1] Crowley, T.J. and North, G.R. (1991) Paleoclimatology. Oxford University Press, New York. [2] Thomas, E. (2008) Descent into the icehouse. Geology, 36, 191-192. doi:10.1130/focus022008.1 [3] Pagani, M., Zachos, J.C., Freeman, K.H., Tipple, B. and Bohaty, S. (2005) Marked decline in atmospheric carbon dioxide concentrations during the Paleogene. Science, 309, 600-603. doi:10.1126/science.1110063 [4] Shellito, C.J., Sloan, L.C. and Huber, M. (2003) Climate model sensitivity to atmospheric CO2 levels in the Early- Middle Paleogene. Palaeogeography, Palaeoclimatology, Palaeoecology, 193, 113-123. doi:10.1016/S0031-0182(02)00718-6 [5] Zachos, J.C., Dickens, G.R. and Zeebe, R.E. (2008) An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics. Nature, 451, 279-283. doi:10.1038/nature06588 [6] Barron, E.J. and Peterson, W.H. (1991) The Cenozoic ocean circulation based on ocean general circulation model results. Palaeogeography, Palaeoclimatology, Palaeoecology, 83, 1-28. doi:10.1016/0031-0182(91)90073-Z [7] Bice, K.L., Scotese, C.R., Seidov, D. and Barron, E.J. (2000) Quantifying the role of geographic change in Cenozoic ocean heat transport using uncoupled atmosphere and ocean models. Palaeogeography, Palaeoclimatology, Palaeoecology, 161, 295-310. doi:10.1016/S0031-0182(00)00072-9 [8] Seidov, D.G. (1986) Auto-oscillations in the system large- scale circulation and synoptic ocean eddies. Isvestiya, Atmospheric and Oceanic Physics, 22, 679-685. [9] Pekar, S.F. (2008) Climate change: When did the icehouse cometh? Nature, 455, 602-603. doi:10.1038/455602a [10] Bell, R.E., Luydendy, B.P. and Wilson, T.J. (2008) Antarctica: A keystone in a changing world. EOS, 89, 4. doi:10.1029/2008EO010005 [11] Pekar, S.F. and Deconto, R.M. (2006) High-resolution ice-volume estimates for the early Miocene: Evidence for a dynamic ice sheet in Antarctica. Palaeogeography, Palaeoclimatology, Palaeoecology, 231, 101-109. doi:10.1016/j.palaeo.2005.07.027 [12] Abreu, V.S. and Anderson, J.B. (1998) Glacial eustacy during the Cenozoic: Sequence stratigraphic implications. American Association Petroleum Geologists Bulletin, 82, 1385-1400. [13] Zachos, J., Pagani, M., Sloan, L., Thomas, E. and Billups, K. (2001) Trends, rhythms, and aberrations in global cli- mate 65 Ma to present. Science, 292, 686-693. doi:10.1126/science.1059412 [14] Lear, C.H., Mawbey, E.M. and Rosenthal, Y. (2010) Cenozoic benthic foraminiferal Mg/Ca and Li/Ca records: Toward unlocking temperatures and saturation states. Paleoceanography, 25, 1-11. doi:10.1029/2009PA001880 [15] Boehme, M. (2003) The miocene climatic optimum: Evidence from ectothermic vertebrates of central Europe. Palaeogeography, Palaeoclimatology, Palaeoecology, 195, 389-401. doi:10.1016/S0031-0182(03)00367-5 [16] Holbourn, A., Kuhnt, W., Schulz, M. and Erlenkeuser, H. (2005) Impacts of orbital forcing and atmospheric carbon dioxide on Miocene ice-sheet expansion. Nature, 438, 483-487. doi:10.1038/nature04123 [17] Langebroek, P.M., Paul, A. and Schulz, M. (2010) Simulating the sea level imprint on marine oxygen isotope re- cords during the middle Miocene using an ice sheet-cli- mate model. Paleoceanography, 25, 1-12. doi:10.1029/2008PA001704 [18] Pagani, M., Caldeira, K., Berner, R. and Beerling, D.J. (2009) The role of terrestrial plants in limiting atmospheric CO2 decline over the past 24 million years. Nature, 460, 85-88. doi:10.1038/nature08133 [19] Deconto, R.M., Pollard, D., Wilson, P.A., Palike, H., Lear, C.H. and Pagani, M. (2008) Thresholds for cenozoic bipolar glaciation. Nature, 455, 652-657. doi:10.1038/nature07337 [20] Kump, L.R. (2009) Tipping pointedly colder. Science, 323, 1175-1176. doi:10.1126/science.1170613 [21] Bice, K.L. and Marotzke, J. (2001) Numerical evidence against reversed thermohaline circulation in the warm Paleocene/Eocene ocean. Journal of Geophysical Research, 106, 11529-511542. doi:10.1029/2000JC000561 [22] Haupt, B.J. and Seidov, D. (2001) Warm deep-water ocean conveyor during the Cretaceous time. Geology, 29, 295-298. doi:10.1130/0091-7613(2001)029<0295:WDWOCD>2.0.CO;2 [23] Haupt, B.J. and Seidov, D. (2007) Strengths and weaknesses of the global ocean conveyor: Inter-basin freshwater disparities as the major control. Progress in Oceanography, 73, 358-369. doi:10.1016/j.pocean.2006.12.004 [24] Seidov, D., Barron, E.J. and Haupt, B.J. (2001) Meltwater and the global ocean conveyor: Northern versus southern connections. Global and Planetary Change, 30, 253-266. doi:10.1016/S0921-8181(00)00087-4 [25] Seidov, D., Sarnthein, M., Stattegger, K., Prien, R. and Weinelt, M. (1996) North Atlantic ocean circulation during the Last Glacial Maximum and subsequent meltwater event: A numerical model. Journal of Geophysical Research, 101, 16305-16332. doi:10.1029/96JC01079 [26] Rahmstorf, S. (1995) Bifurcations of the Atlantic thermohaline circulation in response to changes in the hydrological cycle. Nature, 378, 145-149. doi:10.1038/378145a0 [27] Schmittner, A., Meissner, K.J., Eby, M. and Weaver, A.J. (2002) Forcing of deep ocean circulation in simulation of the Last Glacial Maximum. Paleoceanography, 17, 15. [28] Stocker, T.F., Wright, D.G. and Broecker, W.S. (1992) The influence of high-latitude surface forcing on the global thermohaline circulation. Paleoceanography, 7, 529-541. doi:10.1029/92PA01695 [29] Stouffer, R.J., Seidov, D. and Haupt, B.J. (2007) Climate response to external sources of freshwater: North Atlantic versus the Southern ocean. Journal of Climate, 20, 436- 448. doi:10.1175/JCLI4015.1 [30] Weaver, A.J., Saenko, O.A., Clark, P.U. and Mitrovica, J.X. (2003) Meltwater pulse 1A from Antarctica as a trigger of the B?lling-Aller?d warm interval. Science, 299, 1709-1713. doi:10.1126/science.1081002 [31] Cox, M. and Bryan, K. (1984) A numerical model of the ventilated thermocline. Journal of Physical Oceanography, 14, 674-687. doi:10.1175/1520-0485(1984)014<0674:ANMOTV>2.0.CO;2 [32] Butzin, M., Lohmann, G. and Bickert, T. (2011) Miocene ocean circulation inferred from marine carbon cycle modeling combined with benthic isotope records. Paleoceanography, 26, 1-19. doi:10.1029/2009PA001901 [33] Herold, N., Mueller, R.D. and Seton, M. (2010) Comparing early to middle Miocene terrestrial climate simulations with geological data. Geosphere, 6, 952-961. doi:10.1130/GES00544.1 [34] Dickens, J.M. (2004) Ocean-atmosphere feedback in climate simulations using off-line modules of a coupled ocean- atmosphere model. Master’s Thesis, Pennsylvania State University, University Park. [35] Barron, E.J. and Moore, G.T. (1994) Climate model applications in paleoenvironmental analysis. Geological Society Publishing, Tulsa. [36] Vertenstein, M. and Kluzek, E.B. (1999) User’s guide to LSM1.1. National Center for Atmospheric Research, Boulder. [37] Kluzek, E.B., Olson, J., Rosinski, J.M., Truesdale, J.E. and Vertenstein, M. (1999) User’s guide to NCAR CCM 3.6, National Center for Atmospheric Research, Boulder. [38] Pacanowski, R.C. (1996) User’s guide and reference manual, GFDL Ocean Technical Report, Geophysical Fluid Dynamics Laboratory, Princeton. [39] Herrmann, A.D. (2003) Late Ordovician ocean-climate system and paleobiogeography. Dissertation, Pennsylvania State University, University Park. [40] Herrmann, A.D., Haupt, B.J., Patzkowsky, M.E., Seidov, D. and Slingerland, R.L. (2004) Response of Late Ordovician paleoceanography to changes in sea level, continental drift, and atmospheric pCO2: Potential causes for long-term cooling and glaciation. Palaeogeography, Palaeoclimatology, Palaeoecology, 210, 385-401. doi:10.1016/j.palaeo.2004.02.034 [41] Seidov, D. and Haupt, B.J. (1997) Global ocean thermohaline conveyor at present and in the late Quaternary. Geophysical Research Letters, 24, 2817-2820. doi:10.1029/97GL02913 [42] Seidov, D. and Haupt, B.J. (2003) On sensitivity of ocean circulation to sea surface salinity. Global and Planetary Change, 36, 99-116. doi:10.1016/S0921-8181(02)00177-7 [43] Seidov, D. and Haupt, B.J. (2003) Freshwater teleconnections and ocean thermohaline circulation. Geophysical Research Letters, 30, 1-4. doi:10.1029/2002GL016564 [44] Seidov, D. and Haupt, B.J. (2005) How to run a minimalist's global ocean conveyor. Geophysical Research Letters, 32, 1-4. doi:10.1029/2005GL022559 [45] Eldridge, J., Walsh, D. and Scotese, C.R. (2002) PALEOMAP Paleogeographic Atlas. www.scotese.com [46] Scotese, C.R. (1997) Paleogeographic Atlas, PALEOMAP Progress Report 90-0497. University of Texas at Arlington, Arlington. [47] Scotese, C.R., Ross, M.I. and Schettino, A. (1998) Plate tectonic reconstruction and animation. EOS, 79, 334. 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