The timing of major climate terminations

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doi: 10.1029/97PA01169
Author(s): Raymo, M. E.
Author Affiliation(s): Primary:
Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, Cambridge, MA, United States
Volume Title: Paleoceanography
Source: Paleoceanography, 12(4), p.577-585. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0883-8305 CODEN: POCGEP
Note: In English. 39 refs.; illus., incl. 2 tables
Summary: A simple, untuned "constant sedimentation rate" timescale developed using three radiometric age constraints and eleven δ18O records longer than 0.8 Myr provides strong support for the validity of the SPECMAP timescale of the late Quaternary [Imbrie et al., 1984]. In particular, the present study independently confirms the link between major deglaciations (terminations) and increases in northern hemisphere summer radiation at high latitudes and shows that this correlation is not an artifact of orbital tuning. In addition, the excess ice characteristic of late Quaternary "100-kyr" climate cycles typically accumulates when July insolation at 65°N has been unusually low for more than a full precessional cycle, or >21 kyr, and once established does not last beyond the next increase in summer insolation. Thus, the timing of the growth and decay of large 100-kyr ice sheets, as depicted in the deep sea δ18O record, is strongly (and semipredictably) influenced by eccentricity through its modulation of the orbital precession component of northern hemisphere summer insolation. Copyright 1997 by the American Geophysical Union.
Year of Publication: 1997
Research Program: ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Cenozoic; Isotope ratios; Isotopes; Milankovitch theory; O-18/O-16; Oxygen; Paleo-oceanography; Paleoclimatology; Paleotemperature; Quaternary; SPECMAP; Stable isotopes; Upper Quaternary
Record ID: 2000075392
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.

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