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(Article of periodic en Anglais - 1980)

Document title

Oceanic evidence for the mechanism of rapid northern hemisphere glaciation

Authors(s) and Affiliation(s)

RUDDIMAN W. F. ; McINTYRE A. ; NIEBLER-HUNT V. ; DURAZZI J. T. ;

Abstract

The oxygen isotopic stage 5/4 boundary in deep-sea sediments marks a prominent interval of northern hemisphere ice-sheet growth that lasted about 10,000yr. During much of this rapid ice growth, the North Atlantic Ocean from at least 40N to 60N maintained warm sea-surface temperatures, within 1 to 2C of today's subpolar ocean. This oceanic warmth provided a local source of moisture for ice-sheet accretion on the adjacent continents. The unusually strong thermal gradient off the east coast of North America (an "interglacial" ocean alongside a "glacial" land mass) also should have directed low-pressure storms from warm southern latitudes northward toward the Laurentide Ice Sheet. In addition, minimal calving of ice into the North Atlantic occurred during most of the stage 5/4 transition, indicative of ice retention within the continents. Diminished summer and autumn insolation, a warm subpolar ocean, and minimal calving of ice are conducive to rapid and extensive episodes of northern hemisphere ice-sheet growth.

Source

Article of periodic

published at : Quaternary research New York

Editor :

Millesime : 1980, vol. 13, no1 [pp. 33-64]

Bibliographic references : 50réf.

Language

Anglais

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