Talk by Stefanie Weissbach – Niels Bohr Institute - University of Copenhagen

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Talk by Stefanie Weissbach

Climate signals in stable water isotope records from Northern Greenland

Ice cores from polar ice sheets provide a unique archive for past climatic variations. But due to their remoteness Greenland and Antarctica are up to now mostly unstudied areas.
Deep ice cores represent a single spot. To get an estimate for its regional representativeness and to set the results from deep cores into a wider regional picture more drill sites covering a larger area are necessary.

A set of 13 shallow inter-mediate depth (100-150 m) ice cores drilled during the AWI-North Greenland traverse (NGT) in the 1990ies covering 500 to 1000 years back in time offers the possibility to assess regional representativeness of records like NEEM over that time interval.

Time series of 18-O variation or temperature, respectively, from all firn cores drilled during NGT will be presented.

The oxygen isotopes were measured using mass spectroscopy in a resolution between 3 and 5 cm, yielding records still showing seasonal variations.

Known volcanic eruptions identified by using the DEP and ECM signal were used as time markers and to synchronize the cores.

The goal of this project is to use oxygen isotope data from the NGT cores to improve the knowledge of regional patterns of stable-isotope composition to investigate their variability during the past 500 to 1000 years.