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Titel |
Ultra-high resolution pollen record from the northern Andes reveals rapid shifts in montane climates within the last two glacial cycles |
VerfasserIn |
M. H. M. Groot, R. G. Bogotá, L. J. Lourens, H. Hooghiemstra, M. Vriend, J. C. Berrio, E. Tuenter, J. Plicht, B. Geel, M. Ziegler, S. L. Weber, A. Betancourt, L. Contreras, S. Gaviria, C. Giraldo, N. González, J. H. F. Jansen, M. Konert, D. Ortega, O. Rangel, G. Sarmiento, J. Vandenberghe, T. Hammen, M. Linden, W. Westerhoff |
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. 1 ; Nr. 7, no. 1 (2011-03-22), S.299-316 |
Datensatznummer |
250004412
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Publikation (Nr.) |
copernicus.org/cp-7-299-2011.pdf |
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Zusammenfassung |
Here we developed a composite pollen-based record of
altitudinal vegetation changes from Lake Fúquene (5° N) in Colombia
at 2540 m elevation. We quantitatively calibrated Arboreal Pollen
percentages (AP%) into mean annual temperature (MAT) changes with an
unprecedented ~60-year resolution over the past 284 000 years. An age
model for the AP% record was constructed using frequency analysis in the
depth domain and tuning of the distinct obliquity-related variations to the
latest marine oxygen isotope stacked record. The reconstructed MAT record
largely concurs with the ~100 and 41-kyr (obliquity) paced glacial
cycles and is superimposed by extreme changes of up to 7 to 10°
Celsius within a few hundred years at the major glacial terminations and
during marine isotope stage 3, suggesting an unprecedented North Atlantic – equatorial
link. Using intermediate complexity transient climate modelling
experiments, we demonstrate that ice volume and greenhouse gasses are the
major forcing agents causing the orbital-related MAT changes, while direct
precession-induced insolation changes had no significant impact on the high
mountain vegetation during the last two glacial cycles. |
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