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| Titel |
Implications of Cosmogenic Isotope Linkage for Integration of Terrestrial, Ice and Marine Records and for IntCal Curve Construction |
| VerfasserIn |
Christopher Bronk Ramsey, Raimund Muscheler, Sune Rasmussen, Konrad Hughen, Alan Cooper, Chris Turney |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250145291
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| Publikation (Nr.) |
 EGU/EGU2017-9217.pdf |
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| Zusammenfassung |
| Cosmogenic isotopes provide a basis for linking the timescales of different records on the
assumption that the production rates for different isotopes share a common signal. This has
been shown to be very effective in linking the Greenland GICC05 timescale to the tree-ring
based radiocarbon timescale with decadal precision through the Holocene and into the Late
Glacial. Muscheler et al (this meeting) report that using lower frequency components of the
signal allows linkage over the full range of the radiocarbon timescale. Here we consider
some of the wider implications of linking cosmogenic isotopes between different
records.
Alignment of 10Be and 14C have implications for the integration of environmental records
generally, enabling many of the key environmental archives (terrestrial, ice and marine) to be
compared on timescales with centennial precision, allowing researchers to re-evaluate
assumed synchronisms and potential leads and lags. By using a combination of
age-depth modelling and wiggle-matching methodologies it is possible to generate a
relationship between different timescales with quantified errors. This approach has
consequences for the generation and use of the IntCal calibration curves. Linkage
by cosmogenic isotope signal provides an alternative method to climate tuning
for generating timescales for inclusion in the calibration curve. The relationship
between the ice core timescales and the IntCal timescale is also one which is of critical
importance for robustly comparing radiocarbon dated samples and records into
an environmental context. In addition, the relationships derived between different
record-timescales can be used to assess the synchrony between the climate signals in,
for example, Greenland, the Hulu speleothems, and the Cariaco basin: using the
linkages and their quantified uncertainties it is possible to plot different climate-proxy
data on any of the related age or depth scales. Finally, the linkages seen between
different cosmogenic signals also provides a way to distinguish between signal and
noise in radiocarbon calibration datasets in the time range 25-50ka cal BP, with
implications for the statistical algorithms used in radiocarbon calibration curve generation. |
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