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Titel |
Sub-decadal- to decadal-scale climate cyclicity during the Holsteinian interglacial (MIS 11) evidenced in annually laminated sediments |
VerfasserIn |
A. Koutsodendris, A. Brauer, H. Pälike, U. C. Müller, P. Dulski, A. F. Lotter, J. Pross |
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 ; 7, no. 3 ; Nr. 7, no. 3 (2011-09-21), S.987-999 |
Datensatznummer |
250004624
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Publikation (Nr.) |
copernicus.org/cp-7-987-2011.pdf |
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Zusammenfassung |
To unravel the short-term climate variability during Marine Isotope Stage
(MIS) 11, which represents a close analogue to the Holocene with regard to
orbital boundary conditions, we performed microfacies and time series
analyses on a ~3200-yr-long record of annually laminated Holsteinian
lake sediments from Dethlingen, northern Germany. These biogenic varves
comprise two sub-layers: a light sub-layer, which is controlled by
spring/summer diatom blooms, and a dark sub-layer consisting mainly of
amorphous organic matter and fragmented diatom frustules deposited during
autumn/winter. Time series analyses were performed on the thickness of the
light and dark sub-layers. Signals exceeding the 95% and 99%
confidence levels occur at periods that are near-identical to those known
from modern instrumental data and Holocene palaeoclimatic records. Spectral
peaks at periods of 90, 25, and 10.5 yr are likely associated with the
88-, 22- and 11-yr solar cycles, respectively. This variability is mainly
expressed in the light sub-layer spectra, suggesting solar influence on the
palaeoproductivity of the lake. Significant signals at periods between 3 and
5 yr and at ∼6 yr are strongest expressed in the dark sub-layer
spectra and may reflect an influence of the El Niño-Southern
Oscillation (ENSO) and the North Atlantic Oscillation (NAO) during autumn/winter. Our
results suggest that solar forcing and ENSO/NAO-like variability influenced
central European climate during MIS 11 similarly to the present interglacial,
thus demonstrating the comparability of the two interglacial periods at
sub-decadal to decadal timescales. |
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