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Titel |
Sources of Holocene variability of oxygen isotopes in paleoclimate archives |
VerfasserIn |
A. N. LeGrande, G. A. Schmidt |
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 ; 5, no. 3 ; Nr. 5, no. 3 (2009-08-07), S.441-455 |
Datensatznummer |
250002544
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Publikation (Nr.) |
copernicus.org/cp-5-441-2009.pdf |
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Zusammenfassung |
Variability in water isotopes has been captured in numerous archives and
used to infer past climate changes. Here we examine water isotope
variability over the course of the Holocene using the water-isotope enabled,
coupled atmosphere-ocean general circulation model, GISS ModelE-R. Eight
Holocene time slices, ~1000 years apart are simulated and driven by
estimated changes in orbital configuration, greenhouse gases, and ice sheet
extent. We find that simulated water isotope archives match well with those
seen in ice cores, ocean sediment cores, and speleothems. The climate
changes associated with the water isotope changes, however, are more complex
than simple modern spatial slope interpretations might suggest. In
particular, water isotope variability in Asian speleothems is linked to
alterations in landward water vapor transport, not local precipitation, and
ice sheet changes over North America lead to the masking of temperature
signals in Summit, Greenland. Salinity-seawater isotope variability is
complicated by inter-ocean basin exchanges of water vapor. Water isotopes do
reflect variability in the hydrology, but are better interpreted in terms of
regional hydrological cycle changes rather than as indicators of local
climate. |
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