Open AccessImpact of iceberg melting on Mediterranean thermohaline circulation during Heinrich events
Author(s) -
Sierro F. J.,
Hodell D. A.,
Curtis J. H.,
Flores J. A.,
Reguera I.,
ColmeneroHidalgo E.,
Bárcena M. A.,
Grimalt J. O.,
Cacho I.,
Frigola J.,
Canals M.
Publication year - 2005
Publication title -
paleoceanography
Language(s) - English
Resource type - Journals
eISSN - 1944-9186
pISSN - 0883-8305
DOI - 10.1029/2004pa001051
Subject(s) - oceanography , thermohaline circulation , mediterranean climate , benthic zone , mediterranean sea , foraminifera , geology , iceberg , plankton , north atlantic deep water , climatology , sea ice , geography , archaeology
Down‐core samples of planktonic and benthic foraminifera were analyzed for oxygen and carbon isotopes in International Marine Past Global Changes Study (IMAGES) core MD99‐2343 in order to study the interactions between climate change in the Northern Hemisphere and the western Mediterranean thermohaline circulation at times of Heinrich events (HE). Our results confirm the antiphase correlation between enhanced North Atlantic Deep Water formation and low ventilation in the Mediterranean. However, this study reveals that this antiphase relationship in deepwater formation between the North Atlantic and Mediterranean was interrupted during times of HE when the injection of large volumes of water from melting icebergs reached the entrance to the Mediterranean. These events, which lasted less than 1000 years, are represented by pronounced decreases in both planktonic δ 18 O and benthic δ 13 C signals. Lower salinities of Mediterranean surface water resulted in a slowdown of western Mediterranean deepwater overturn even though cold sea surface temperatures and drier climate should have resulted in enhanced deepwater formation.