Open AccessA dramatic Atlantic dissolution event at the onset of the last glaciation
Author(s) -
Broecker Wallace,
Clark Elizabeth
Publication year - 2001
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2001gc000185
Subject(s) - glacial period , geology , north atlantic deep water , oceanography , foraminifera , interglacial , thermohaline circulation , paleontology , benthic zone
Measurements of the CaCO 3 content of the CaCO 3 size index and of foraminifera weights demonstrate that a prominent dissolution event occurred in the western equatorial Atlantic at the onset of the last glacial period. The decrease in CO 3 = ion concentration appears to have been too large to be accounted for by the ocean acidification associated with the demise of excess interglacial biomass. Rather, it appears to have been the result of a temporary strengthening of the penetration of the glacial equivalent Antarctic Bottom Water into the Atlantic. The co‐occurrence of massive Ethmodiscus rex deposition in the eastern equatorial Atlantic bears witness to a reorganization of circulation in the Atlantic. This reorganization may well reflect a temporary collapse of conveyor circulation at the onset of the last glaciation.