DOI: 10.1038/ngeo2267
论文题名: Subtropical iceberg scours and meltwater routing in the deglacial western North Atlantic
作者: Hill J.C. ; Condron A.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2014
卷: 7, 期: 11 起始页码: 806
结束页码: 810
语种: 英语
Scopus关键词: bathymetry
; coastal current
; deglaciation
; discharge
; ice sheet
; iceberg
; meltwater
; oceanic circulation
; scour
; simulation
; subtropical region
; Atlantic Ocean
; Atlantic Ocean (North)
英文摘要: Abrupt centennial-to-millennial shifts in Northern Hemisphere climate during the last deglaciation are thought to have been triggered by the discharge of large volumes of meltwater and icebergs to the subpolar North Atlantic1. Here we show that meltwater and icebergswere also transported directly fromthe Laurentide ice margin to the subtropical NorthAtlantic in a narrow coastal current. We present high-resolution bathymetric data from south of Cape Hatteras showing numerous scours that we interpret as relict iceberg keel marks. This indicates that icebergs up to 300m thick drifted to southern Florida (24.5° N). In simulations with an ocean circulation model, during deglaciation, freshwater and icebergs routinely reached as far south as 32.5° N, in a period of less than four months. The southernmost scours formed only during periods of high meltwater discharge fromthe Northern Hemisphere ice sheets. In the simulations, such extreme periods of meltwater release led to a reversal of the typically northward surface flow in the nearshore subtropical western North Atlantic. We therefore suggest that significant volumes of iceberg-laden meltwater routinely bypassed subpolar regions and spread across the subtropical North Atlantic. © 2014 Macmillan Publishers Limited. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/106386
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: Center for Marine and Wetland Studies, Coastal Carolina University, Conway, South Carolina, United States; Climate System Research Center, Department of Geosciences, University of Massachusetts, Amherst, Massachusetts, United States
Recommended Citation:
Hill J.C.,Condron A.. Subtropical iceberg scours and meltwater routing in the deglacial western North Atlantic[J]. Nature Geoscience,2014-01-01,7(11)