HR: 10:50h
AN: PP31D-03 INVITED     [PDF]
TI: The Last Interglacial in the Northern and Southern Hemispheres
AU: * McManus, J F
EM: jmcmanus@whoi.edu
AF: Dept of Geology and Geophysics, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 United States
AU: Hoffmann, S S
EM: shoffmann@whoi.edu
AF: Dept of Geology and Geophysics, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 United States
AU: Oppo, D W
EM: doppo@whoi.edu
AF: Dept of Geology and Geophysics, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 United States
AU: Johnsen, S J
EM: sigfus@mail.gfy.ku.dk
AF: Niels Bohr institute for Astronomy, University of Copenhagen, Department of Geophysics, Copenhagen, 00000 Denmark
AU: Cullen, J L
EM: james.cullen@salemstate.edu
AF: Salem State College, Dept. of Geol., Salem, MA 01970 United States
AU: Cosier, S
EM: SuSEC8@aol.com
AF: Dept of Geology and Geophysics, Woods Hole Oceanographic Institution, 360 Woods Hole Road, Woods Hole, MA 02543 United States
AB: Evidence from several North Atlantic deep-sea sediment cores indicates that interglacial warmth outlasted the ice volume minimum during marine isotope substage 5e (MIS5e). It has been suggested that this lag may be the result of northward heat transport by a vigorous meridional overturning circulation at the same time that glaciers began to build up during MIS 5d. We first examine this temporal relationship of warm sea-surface temperatures (SST) and ice growth to confirm the spatial pattern of prolonged warmth. We then show a close correspondence between deep-sea cores and the new North Grip isotope record from Greenland, demonstrating a regional coherence to the climate pattern. We next investigate two proxies for the deep circulation, benthic d13C and 231Pa/230Th, from the Atlantic, in combination with a new benthic d13C record from the deep Pacific. Finally we compare proxies for the surface and deep hydrography in the North Atlantic to new records from sites in the Southern hemisphere in order to determine the phasing of hydrographic changes in the respective hemispheres before, during and after MIS 5e. One southern site is in the western subtropical Atlantic near the Brazil margin. The other is in the eastern subpolar Pacific, near the Chilean margin. Our results provide insights into the deepwater-climate connection between north and south.
DE: 1620 Climate dynamics (3309)
DE: 4267 Paleoceanography
DE: 4808 Chemical tracers
DE: 4866 Sorptive scavenging
DE: 4870 Stable isotopes
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2003 Fall Meeting