Oceanic Evidence for the Mechanism of Rapid Northern Hemisphere Glaciation
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 10,000 yr. During much of this rapid ice growth, the North Atlantic Ocean from at least 40°N to 60°N maintained warm sea-surface temperatures, wi...
| Published in: | Quaternary Research |
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| Main Authors: | , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Cambridge University Press (CUP)
1980
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1016/0033-5894(80)90081-2 http://api.elsevier.com/content/article/PII:0033589480900812?httpAccept=text/xml http://api.elsevier.com/content/article/PII:0033589480900812?httpAccept=text/plain https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033589400015246 |
| Summary: | 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 10,000 yr. During much of this rapid ice growth, the North Atlantic Ocean from at least 40°N to 60°N maintained warm sea-surface temperatures, within 1° to 2°C 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 north-ward 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. |
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