Comprehensive 1000 year climatic history from an intermediate depth ice core from the south dome Berkner Island, Antarctica: methodics, dating, and first results
A 181 m deep ice core from the Berkner Island South Dome was ana-lyzed for stable isotopes, mayor ions and microparticle concentrations.Samples for Ion Chromatography were prepared by using a novel tech-nique of ?lling decontaminated sample from a device for continuous icecore melting directly into the sample vials. The core was dated throughidentication of volcanic horizons and interpolative layer counting. Thecore reveals - together with a similar core from the North Dome - a1000 year history of relatively stable climate. ± 18 O and the chemi-cal composition show variations on a multi-decadal to centennial timescale. Temporal variations in both cores deviate from each other owingto changing patterns of regional scale circulation patterns. Increasingannual accumulation is observed for the last 100 years. A period ofincreased sea salt concentrations started around 1400 AD, which hasalso been seen in selected other cores. Microparticle concentrationsare enhanced from 1200 - 1350 AD; this may be caused by a higheratmospheric mineral dust load or by volcanic activity stronger thanpreviously thought. Microparticles and NH 4+ show marked but veryirregular seasonal peaks; long term seasonal averages are maximal in austral spring or mid summer, respectively. Postdepositional loss ofMSA and NO¡ 3 during ice core storage was observed at densities ?0.85 g cm¡ 3 . Postdepositional redistribution was observed for MSA,NO¡ 3 and F¡ at volcanic horizons.
Helmholtz Research Programs > MARCOPOLI (2004-2008) > POL6-Earth climate variability since the Pliocene