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| Titel |
Past climate variability between 97 and 7 ka reconstructed from a multi
proxy speleothem record from Western Cuba |
| VerfasserIn |
Sophie Winterhalder, Denis Scholz, Augusto Mangini, Christoph Spötl, Klaus Peter Jochum, Jesús M. Pajón |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250132387
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| Publikation (Nr.) |
 EGU/EGU2016-12894.pdf |
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| Zusammenfassung |
| The tropical hydrological cycle plays a key role in regulating global climate, mainly through
the export of heat and moisture to higher latitudes, and is highly sensitive to climate change,
for instance due to changes in the position of the Intertropical Convergence Zone (ITCZ).
Previous work on Caribbean stalagmites suggests a strong connection of precipitation
variability to North Atlantic (NA) sea surface temperatures on multidecadal to millenial
timescales (Fensterer et al., 2012; Fensterer et al., 2013; Winter et al., 2011). Cold
phases in the NA potentially lead to a southward shift of the ITCZ and thus drier
conditions in Cuba. On orbital timescales, Cuban stalagmites suggest a relation of
speleothem δ18O values with the δ18O value of Caribbean surface waters (Fensterer et al.,
2013).
Here we present an expansion of the Cuban speleothem record covering the whole last
glacial period from the end of MIS5c (97 ka BP) until 7 ka with hiatuses between 93-80 ka,
37-35 ka and 13-10 ka. Stalagmite Cuba medio (CM) has been precisely dated with
60 230Th/U-ages, mainly performed by the MC-ICPMS technique. The δ18O and
δ13C records are completed by a continuous, high resolution LA-ICPMS trace
element profile. These data allow for the first time to establish a multi-proxy climate
reconstruction for the North Western Caribbean at decadal to centennial resolution for this
period.
The long-term variability of the δ18O values probably reflects rainfall amount in Cuba.
The response to some Dansgaard/Oeschger and Heinrich stadials confirms the previously
observed correlation between Caribbean and NA climate variability. However, this
connection is not clearly imprinted throughout the record. Furthermore, trace elements, such
as Mg, do not proof without ambiguity drier conditions in Cuba during NA cold events, such
as the Heinrich stadials. This suggests that climate variability in Cuba was more complex
during the last 100ka, and that the NA was not the only driving factor. Due to the
competing influence of the NA, the Gulf of Mexico and the Pacific Ocean, the proposed
severe changes in the tropical hydrological cycle during that time (such as variations
of the ITCZ, insolation and the thermohaline circulation (THC)) have potentially
lead to significant changes in sources and trajectories of precipitation in Western
Cuba. Our record, thus, provides an important contribution towards understanding
and differentiating these parameters on Caribbean climate during glacial climate
changes.
References:
Fensterer, C., Scholz, D., Hoffmann, D., Spötl, C., Pajón, J.M., Mangini, A., 2012. Cuban
stalagmite suggests relationship between Caribbean precipitation and the Atlantic
Multidecadal Oscillation during the past 1.3 ka. The Holocene, 0959683612449759.
Fensterer, C., Scholz, D., Hoffmann, D.L., Spötl, C., Schröder-Ritzrau, A., Horn, C.,
Pajón, J.M., Mangini, A., 2013. Millennial-scale climate variability during the last 12.5
ka recorded in a Caribbean speleothem. Earth and Planetary Science Letters 361,
143-151.
Winter, A., Miller, T., Kushnir, Y., Sinha, A., Timmermann, A., Jury, M.R., Gallup, C.,
Cheng, H., Edwards, R.L., 2011. Evidence for 800years of North Atlantic multi-decadal
variability from a Puerto Rican speleothem. Earth and Planetary Science Letters 308, 23-28. |
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