In:
Global Biogeochemical Cycles, American Geophysical Union (AGU), Vol. 12, No. 3 ( 1998-09), p. 409-427
Kurzfassung:
We investigate the response of the calcite lysocline to changes in the export production of the low‐latitude surface ocean (the combined equatorial, tropical, and subtropical regions). We employ different CaCO 3 throughput schemes in a time‐dependent ocean carbon cycle model to separate the CaCO 3 production/lysocline balance from the other components of the model response and to estimate the effect of dissolution driven by organic matter decomposition in surface sediments. With this model, we carry out three experiments based on previous hypotheses for the cause of glacial/interglacial atmospheric CO 2 variations: (1) a simple increase in low‐latitude production, (2) a decrease in its CaCO 3 /organic carbon rain ratio, and (3) an increase in the depth of organic carbon regeneration. None of these changes, when taken alone, can lower atmospheric CO 2 to glacial levels without violating observations of the glacial lysocline depth. If a low‐latitude production increase were accompanied by a decrease in the CaCO 3 /organic carbon rain ratio, then these simultaneous changes could lower atmospheric CO 2 to observed glacial levels without causing a significant change in the ocean‐average depth of the lysocline. However, even with these simultaneous changes, the required increase in production is 50% or more of the modern rate of production.
Materialart:
Online-Ressource
ISSN:
0886-6236
,
1944-9224
Sprache:
Englisch
Verlag:
American Geophysical Union (AGU)
Publikationsdatum:
1998
ZDB Id:
2021601-4
SSG:
12
SSG:
13
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