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| Titel |
Variability of sea surface temperature and sea ice extent in Kongsfjorden, Svalbard during the last 2 000 years |
| VerfasserIn |
Tiia Luostarinen, Arto Miettinen, Katrine Husum |
| 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 |
250138089
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| Publikation (Nr.) |
 EGU/EGU2017-1007.pdf |
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| Zusammenfassung |
| The climate on the western and northern Spitsbergen margin is strongly dependent on the
inflow of warm and saline Atlantic Water (AW), which is the largest heat source of the
Arctic Ocean. Any changes in the inflow of AW can have a major impact on the
environment of the area. The inflow has been especially strong during the last 30 years.
As the Arctic is going through rapid changes, studies on past climate variability
and environmental change are needed to understand the long-term effects of these
changes.
In this study we investigate sea surface temperatures (SST) and sea ice variability in high
temporal resolution using marine subfossil diatom assemblages from Kongsfjorden. The
quantitative diatom-based August SST reconstruction is the northernmost reported to date.
The oceanographic conditions in Kongsfjorden are strongly related to the characteristics of
the West Spitsbergen Current (WSC), which transports AW and therefore also heat and salt
into the Arctic Ocean.
A 50 cm long marine sediment core NP15-Kb0 is analyzed for diatoms at 1.0 cm
intervals. The preliminary age model based on three AMS 14C dates indicates that the core
represents approximately an interval 500-1500 Common Era (CE). A diatom calibration set
consisting of 183 surface sediment samples from the North Atlantic is used to convert diatom
counts to SSTs using a weighted-averaging partial least squares (WA-PLS) transfer function
method. The qualitative sea ice reconstruction is based on the occurrence of diatom species
belonging to Marginal Ice Zone assemblage. This study brings more information about ocean
surface conditions in NW Svalbard during the Medieval Climate Anomaly, which is
important considering the present warming conditions of this climatically sensitive area. |
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