Format

Send to:

Choose Destination
See comment in PubMed Commons below
Science. 2014 Nov 14;346(6211):847-51. doi: 10.1126/science.1255586. Epub 2014 Oct 23.

Paleoceanography. Antarctic role in Northern Hemisphere glaciation.

Author information

  • 1Department of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08901, USA. woodard@marine.rutgers.edu.
  • 2Department of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08901, USA. Department of Earth and Planetary Sciences, Rutgers University, 610 Taylor Road, Piscataway, NJ 08845, USA.
  • 3Department of Earth and Planetary Sciences, Rutgers University, 610 Taylor Road, Piscataway, NJ 08845, USA.
  • 4Department of Geology and Environmental Geosciences, Lafayette College, 730 High Street, Easton, PA 18042, USA.

Abstract

Earth's climate underwent a major transition from the warmth of the late Pliocene, when global surface temperatures were ~2° to 3°C higher than today, to extensive Northern Hemisphere glaciation (NHG) ~2.73 million years ago (Ma). We show that North Pacific deep waters were substantially colder (4°C) and probably fresher than the North Atlantic Deep Water before the intensification of NHG. At ~2.73 Ma, the Atlantic-Pacific temperature gradient was reduced to <1°C, suggesting the initiation of stronger heat transfer from the North Atlantic to the deep Pacific. We posit that increased glaciation of Antarctica, deduced from the 21 ± 10-meter sea-level fall from 3.15 to 2.75 Ma, and the development of a strong polar halocline fundamentally altered deep ocean circulation, which enhanced interhemispheric heat and salt transport, thereby contributing to NHG.

Copyright © 2014, American Association for the Advancement of Science.

PMID:
25342658
[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk