HR: 0800h
AN: PP41C-0692    [Abstracts]
TI: Significant differences between the millennial variability in IRD of the last and penultimate glaciations in the North Atlantic
AU: * Obrochta, S P
EM: stephen.obrochta@duke.edu
AF: Duke University Division of Earth and Ocean Science, Box 90227, Durham, NC 27704, United States
AU: Crowley, T J
EM: crowley@staffmail.ed.ac.uk
AF: University of Edinburgh School of GeoSciences, Grant Institute, The King's Buildings, West Mains Road, Edinburgh EH9 3JW, Edinburgh, EH9 3JW, United Kingdom
AB: The complete, high-resolution (approx. 250 year sampling interval) MIS-6 record of hematite-stained grains (HSG) and Icelandic volcanic glass at IODP Site U1308 (reoccupied DSDP 609) indicates that significant differences in millennial climate variability existed between the last and penultimate glaciations. Relative to the last glaciation, 1) HSG cyclicity is lower in amplitude and not as well developed; 2) HSG and glass do not covary; 3) Glass is virtually absent during several intervals. While both the HSG and glass records exhibit 3-sigma significant periodicity at ~ 950 and ~ 1075 years, respectively, without further evaluation of age model uncertainties, it is unclear whether these records are truly periodic.
DE: 4901 Abrupt/rapid climate change (1605)
DE: 4926 Glacial
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting