Open AccessOcean climate variability in the eastern North Atlantic during interglacial marine isotope stage 11: A partial analogue to the Holocene?
Author(s) -
de Abreu Lúcia,
Abrantes Fátima F.,
Shackleton Nicholas J.,
Tzedakis Polychronis C.,
McManus Jerry F.,
Oppo Delia W.,
Hall Michael A.
Publication year - 2005
Publication title -
paleoceanography
Language(s) - English
Resource type - Journals
eISSN - 1944-9186
pISSN - 0883-8305
DOI - 10.1029/2004pa001091
Subject(s) - interglacial , geology , holocene , marine isotope stage , oceanography , glacial period , foraminifera , holocene climatic optimum , upwelling , stage (stratigraphy) , paleontology , sea surface temperature , benthic zone , paleoclimatology , climatology , climate change
Similar orbital geometry and greenhouse gas concentrations during marine isotope stage 11 (MIS 11) and the Holocene make stage 11 perhaps the best geological analogue period for the natural development of the present interglacial climate. Results of a detailed study of core MD01‐2443 from the Iberian margin suggest that sea surface conditions during stage 11 were not significantly different from those observed during the elapsed portion of the Holocene. Peak interglacial conditions during stage 11 lasted nearly 18 kyr, indicating a Holocene unperturbed by human activity might last an additional 6–7 kyr. A comparison of sea surface temperatures (SST) derived from planktonic foraminifera for all interglacial intervals of the last million years reveals that warm temperatures during peak interglacials MIS 1, 5e, and 11 were higher on the Iberian margin than during substage 7e and most of 9e. The SST results are supported by heavier δ 18 O values, particularly during 7e, indicating colder SSTs and a larger residual ice volume. Benthic δ 13 C results provide evidence of a strong influence of North Atlantic Deep Water at greater depths than present during MIS 11. The progressive ocean climate deterioration into the following glaciation is associated with an increase in local upwelling intensity, interspersed by periodic cold episodes due to ice‐rafting events occurring in the North Atlantic.