Diatom, ice rafted debris and Neogloboquadrina pachyderma (sinistral) abundance in sediment core OCE326-GGC14 ...

A high-resolution diatom census coupled with other proxy data from Laurentian Fan (LF) provides a detailed description of the last deglaciation, bringing new insight to that period by revealing directly the timing of sea-ice formation and melting. Cold events Heinrich Event 1 (H1) and the Younger Dr...

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Bibliographic Details
Main Authors: Gil, Isabelle M, Keigwin, Lloyd D, Abrantes, Fatima F
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA 2015
Subjects:
Online Access:https://dx.doi.org/10.1594/pangaea.854452
https://doi.pangaea.de/10.1594/PANGAEA.854452
Description
Summary:A high-resolution diatom census coupled with other proxy data from Laurentian Fan (LF) provides a detailed description of the last deglaciation, bringing new insight to that period by revealing directly the timing of sea-ice formation and melting. Cold events Heinrich Event 1 (H1) and the Younger Dryas (YD) were multiphase events. H1 (~16.8-15.7 cal kyr BP) was defined by a two-pulse release of icebergs promoting sea-ice formation. Melting of sea-ice after H1 corresponds to a cold and fresh anomaly that may have kept the Bølling colder than the Allerød. At ~13.6 cal kyr BP, a cooling trend culminated with sea-ice formation, marking the YD onset (~12.8 cal kyr BP). The decrease in sea-ice (~12.2 cal kyr BP) led to a YD second phase characterized by very cold winters. However, the contribution of warm water diatoms tends to increase at the same time and the YD gradual end (~11.6 cal kyr BP) contrasts with its abrupt end in Greenland ice cores. The YD cannot be regarded as an event triggered by a fresh water ...