Journal article icon

Journal article

Oxygen depletion recorded in upper waters of the glacial Southern Ocean

Abstract:
Oxygen depletion in the upper ocean is commonly associated with poor ventilation and storage of respired carbon, potentially linked to atmospheric CO2levels. Iodine to calcium ratios (I/Ca) in recent planktonic foraminifera suggest that values less than ~2.5 μmol/mol indicate the presence of O2-depleted water. We apply this proxy to estimate past dissolved oxygen concentrations in the near surface waters of the currently well oxygenated Southern Ocean, which played a critical role in carbon sequestration during glacial times. A down-core planktonic I/Ca record from South of the Antarctic Polar Front (APF) shows that minimum O2concentrations in the upper ocean fell below 70 μmol/kg during the last two glacial periods, indicating persistent glacial O2-depletion at the heart of the carbon engine of Earth’s climate system. These new estimates of past ocean oxygenation variability may assist in resolving mechanisms responsible for the much-debated ice age atmospheric CO2decline.
Publication status:
Published
Peer review status:
Peer reviewed

Actions


Access Document


Publisher copy:
10.1038/ncomms11146

Authors


More by this author
Institution:
University of Oxford
Division:
MPLS
Department:
Earth Sciences
Role:
Author


Publisher:
Nature Publishing Group
Journal:
Nature Communications More from this journal
Volume:
7
Article number:
11146
Publication date:
2016-02-01
Acceptance date:
2016-02-24
DOI:
ISSN:
2041-1723


Pubs id:
pubs:607752
UUID:
uuid:47d777f6-1709-42ff-9209-872c9d26f9b6
Local pid:
pubs:607752
Source identifiers:
607752
Deposit date:
2016-03-04

Terms of use



Views and Downloads






If you are the owner of this record, you can report an update to it here: Report update to this record

TO TOP