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  • North Atlantic Ice‐Rafting, Ocean and Atmospheric Circulation During the Holocene: Insights From Western Mediterranean Speleothems
Title: North Atlantic Ice‐Rafting, Ocean and Atmospheric Circulation During the Holocene: Insights From Western Mediterranean Speleothems
Abstract In this study, we present a Holocene rainfall index based on three high‐resolution speleothem records from the Western Mediterranean, a region under the influence of the westerly winds belt modulated by the North Atlantic Oscillation (NAO). On centennial to millennial timescales, we show that the North Atlantic ice‐rafting events were likely associated with negative NAO‐like conditions during the Early Holocene and the Late Holocene. However, our data reveal that this is not clearly the case for the mid‐Holocene ice‐rafting events, during which we also show evidence of positive NAO‐like patterns from other paleo‐oceanographic and paleo‐atmospheric data. Hence, contradictory mechanisms involving prolonged periods of both north and south shifts of the westerly winds belt (resembling positive and negative NAO‐like patterns) might at least partially trigger or amplify the ice‐rafting events and the slowdown of the Atlantic Meridional Overturning Circulation.  more » « less
Award ID(s):
1702816
PAR ID:
10360141
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
46
Issue:
13
ISSN:
0094-8276
Page Range / eLocation ID:
p. 7614-7623
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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