In:
Science, American Association for the Advancement of Science (AAAS), Vol. 343, No. 6177 ( 2014-03-21), p. 1347-1350
Abstract:
John H. Martin, who discovered widespread iron limitation of ocean productivity, proposed that dust-borne iron fertilization of Southern Ocean phytoplankton caused the ice age reduction in atmospheric carbon dioxide (CO 2 ). In a sediment core from the Subantarctic Atlantic, we measured foraminifera-bound nitrogen isotopes to reconstruct ice age nitrate consumption, burial fluxes of iron, and proxies for productivity. Peak glacial times and millennial cold events are characterized by increases in dust flux, productivity, and the degree of nitrate consumption; this combination is uniquely consistent with Subantarctic iron fertilization. The associated strengthening of the Southern Ocean’s biological pump can explain the lowering of CO 2 at the transition from mid-climate states to full ice age conditions as well as the millennial-scale CO 2 oscillations.
Type of Medium:
Online Resource
ISSN:
0036-8075
,
1095-9203
DOI:
10.1126/science.1246848
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2014
detail.hit.zdb_id:
128410-1
detail.hit.zdb_id:
2066996-3
detail.hit.zdb_id:
2060783-0
SSG:
11
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