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Titel |
Modeling variations of marine reservoir ages during the last 45 000 years |
VerfasserIn |
J. Franke, A. Paul, M. Schulz |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1814-9324
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Digitales Dokument |
URL |
Erschienen |
In: Climate of the Past ; 4, no. 2 ; Nr. 4, no. 2 (2008-06-25), S.125-136 |
Datensatznummer |
250001626
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Publikation (Nr.) |
copernicus.org/cp-4-125-2008.pdf |
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Zusammenfassung |
When dating marine samples with 14C, the reservoir-age effect is usually
assumed to be constant, although atmospheric 14C production rate and
ocean circulation changes cause temporal and spatial reservoir-age
variations. These lead to dating errors, which can limit the interpretation
of cause and effect in paleoclimate data. We used a global ocean circulation
model forced by transient atmospheric Δ14C variations to calculate
reservoir ages for the last 45 000 years for a present day-like and a last
glacial maximum-like ocean circulation. A ~30% reduced Atlantic
meridonal overturning circulation leads to increased reservoir ages by up to
~500 years in high latitudes. Temporal variations are proportional to
the absolute value of the reservoir age; regions with large reservoir age
also show large variation. Temporal variations range between ~300 years
in parts of the subtropics and ~1000 years in the Southern Ocean. For
tropical regions, which are generally assumed to have nearly stable reservoir
ages, the model suggests variations of several hundred years. |
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