Jerry McManus (WHOI),
James Cullen (Salem State College)
We have carried out several investigations on the duration and stability of previous interglacials, especially MIS 11 and MIS 5. Such studies provide insight into the stability and future of our current interglacial. Below, is the abstract of our most recent publication, in press in Quaternary Science Reviews. Our results suggest that peak warmth of last interglacial was shorter than previously thought.
Evolution and Demise of the Last Interglacial Warmth in the Subpolar North Atlantic
Delia W. Oppo, Jerry F. McManus, James L. Cullen
Abstract - Detailed faunal, isotopic, and lithic marine records provide new insight into the stability and climate progression of the last interglacial period, Marine Isotope Stage (MIS) 5, which peaked approximately 125,000 years ago. In the eastern subpolar North Atlantic, at the latitude of the Ireland, interglacial warmth of the ice volume minimum of substage 5e (MIS 5e) lasted ~10 thousand years (10 kyr) and its demise occurred in two cooling steps. The first cooling step marked the end of the climatic optimum, which 2-3 kyr. Minor ice rafting accompanied each cooling step, the second, larger, step encompassing cold events C26 and C25 previously identified in the northwestern Atlantic. Approximately ~4?C cooling occurred between peak interglacial warmth and C25, and the region experienced an additional temporary cooling of at least 1-2?C during C24, a cooling event associated with widespread ice rafting in the North Atlantic. Beginning with C24, MIS 5 was characterized by oscillations of at least 1-2?C superimposed on a generally cool baseline. The results of this study imply that the marine climatic optimum of the last interglacial was shorter than previously thought. The finding that the eastern subpolar North Atlantic cooled significantly before C24 reconciles terrestrial evidence for progressive climate deterioration at similar and lower latitudes with marine conditions. Our results also demonstrate a close association between modest ice rafting, cooling, and deep ocean circulation even during the peak of MIS 5e and in the earliest stages of ice growth.
Other Related Publications
Sprovieri, R., E. Di Stefano, A. Incarbona and D. W. Oppo, Suborbital climate variability during marine isotope stage 5 in the Mediterranean basin: evidence from planktonic foraminifera and calcareous nannofossil relative abundance fluctuations, Quaternary Science Reviews. 25 2332?2342, 2006.
de Abreu, L., F. Abrantes, N. J. Shackleton, P. C. Tzedakis, J. F. McManus, D. W. Oppo, and M. A. Hall, Ocean climate variability in the Eastern North Atlantic during interglacial MIS 11: A partial analogue to the Holocene?, Paleoceanography, 20, PA3009, doi:10.1029/2004PA001091, 2005.
Jackson, M., N. Oskarsson, R. G. Tr?nnes, J. F. McManus, D. W. Oppo, K. Gronvold, S. R. Hart, J. P. Sachs, Holocene loess deposition in Iceland: Evidence for millenial-scale atmosphere-ocean coupling in the North Atlantic, Geology, 33, 509?512; doi: 10.1130/G21489.1, 2005.
Draut, A. E., Raymo, M. E., McManus, J. F., Oppo, D. W. Climate stability during the Pliocene warm, Paleoceanography, 18, doi:10.1029/2003PA000889, 2003.
Huesser, L. and D. Oppo, Millennial- and orbital-scale climate variability in southeastern United States and in the subtropical Atlantic during Marine Isotope Stage 5: evidence from pollen and isotopes in ODP Site 1059, Earth and Planet. Sci. Letts., 214, 283-290, 2003.
Oppo, D. W., J. F. McManus, and J. L. Cullen, Deepwater variability in the Holocene Epoch, Nature 422, 277-278, 2003.
Rasmusssen, T. L, D. W. Oppo, E. Thompson, S. J. Lehman, Deep sea records from the southeast Labrador Sea: Ocean circulation changes and ice-rafting events during the last 160,000 years, Paleoceanography, 18, doi:10.1029/2001PA000736, 2003.
McManus, J. F., D. W. Oppo, J. L. Cullen, and S. L. Healey, Marine Isotope Stage 11 (MIS 11): Analog for Holocene and future climate? In "Geophysical Monograph 137, Earth's Climate and Orbital Eccentricity: The Marine Isotope Stage 11 Question." (A. Droxler, R. Poore, L. Burckle, and L. Osterman, Eds.), pp. 69-85. AGU, 2003.
McManus, J.F., Oppo, D.W., Keigwin, L.D. and Cullen, J.L.. Prolonged interglacial warmth in the North Atlantic and the onset of the last Pleistocene ice age. Quaternary Research, 58, 17-21, 2002.
Oppo, D. W., L. D. Keigwin, J. F. McManus, and J. L. Cullen, Evidence for millennial scale variability during Marine Isotope Stage 5 and Termination II, Paleoceanography, 16, 280-292, 2001.
McManus, J. F., D. W. Oppo, J. L. Cullen, 0.5 Million years of millennial-scale climate variability in the North Atlantic, Science, 283, 971-975, 1999.
Raymo, M. E., K. Ganley, S. Carter, D. W. Oppo, and J. McManus, High latitude climate instability in the Early Pleistocene, Nature, 392, 699-702, 1998.
Oppo, D. W., J. F. McManus, and J. L. Cullen, Abrupt Climate Events 500,000 - 340,000 years ago: Evidence From subpolar North Atlantic sediments, Science, 279, 1335-1338, 1998.
Oppo, D. W., M. Horowitz, S.J. Lehman, Marine core evidence for reduced deep water production during Termination II followed by a relatively stable substage 5e (Eemian), Paleoceanography, 12, 51-63, 1997.