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| Titel |
Temperature variability at Dürres Maar, Germany during the Migration Period and at High Medieval Times, inferred from stable carbon isotopes of Sphagnum cellulose |
| VerfasserIn |
R. Moschen, N. Kühl, S. Peters, H. Vos, A. Lücke |
| 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 (2011-09-27), S.1011-1026 |
| Datensatznummer |
250004626
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| Publikation (Nr.) |
 copernicus.org/cp-7-1011-2011.pdf |
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| Zusammenfassung |
| This paper presents a high resolution reconstruction of local growing season
temperature (GST) anomalies at Dürres Maar, Germany, spanning the last
two millennia. The GST anomalies were derived from a stable carbon isotope
time series of cellulose chemically extracted from Sphagnum leaves (δ13Ccellulose) separated from a kettle-hole peat deposit of
several metres thickness. The temperature reconstruction is based on the
Sphagnum δ13Ccellulose/temperature dependency observed in
calibration studies. Reconstructed GST anomalies show considerable
centennial and decadal scale variability. A cold and presumably wet
phase with below-average temperature is reconstructed between the 4th
and 7th century AD which is in accordance with the so called European
Migration Period, marking the transition from the Late Roman Period to the
Early Middle Ages. At High Medieval Times, the amplitude in the reconstructed
temperature variability is most likely overestimated; nevertheless,
above-average temperatures are obvious during this time span, which are
followed by a temperature decrease. On the contrary, a pronounced Late Roman
Climate Optimum, often described as similarly warm or even warmer as medieval
times, could not be detected. The temperature signal of the Little Ice Age
(LIA) is not preserved in Dürres Maar due to considerable peat cutting
that takes place in the first half of the 19th century. The local GST
anomalies show a remarkable agreement to northern hemispheric temperature
reconstructions based on tree-ring datasets and are also in accordance with
climate reconstructions on the basis of lake sediments, glacier advances and
retreats, and historical datasets. Most notably, e.g., during the Early
Middle Ages and at High Medieval Times, temperatures were neither low nor high in
general. Rather high frequency temperature variability with multiple narrow
intervals of below- and above-average temperatures at maximum lasting a few
decades are reconstructed. Especially the agreements between our estimated
GST anomalies and temperature reconstructions derived from tree-ring
chronologies indicate the great potential of Sphagnum δ13Ccellulose
time series from peat deposits for palaeoclimate research. This is
particularly the case, given that a quantitative δ13Ccellulose/temperature relationship has been found for several
Sphagnum species. Although the time resolution of Sphagnum δ13Ccellulose
datasets certainly wouldn't reach the annual resolution of tree-ring data,
reconstructions of past temperature variability on the basis of this proxy
hold one particular advantage: often due to relatively high peat
accumulation rates, especially in kettle-hole bogs accumulated on temperate
latitudes over periods of up to several millennia, they allow extending
temperature reconstructions based on tree-ring series into the past to
enhance our knowledge of natural climate variability during the Holocene. |
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