Chemical profiles accross the last glacial termination: First results from the EPICA-DML ice core

The European Project of Ice Coring in Antarctica (EPICA) aims at reconstructing past climate andenvironmental conditions from two deep ice cores in Antarctica. The two cores are drilled in theDome C area (at 75°06' S, 123° 21'E, 3233m a.s.l.) and in Droning Maud Land (DML, at 75°00'S;00°04'E, 2892 m.a.s.l). Here we will present chemical data from the first approx. 1550 m of theDML core.Continuous ice core melting was employed for sample preparation and decontamination.Continuous profiles were measured on-line for Na, Ca and NH4 soluble ion concentrations bycontinuous flow analysis (CFA) methods as well as for insoluble microparticle concentrationstarting at 113m depth. These profiles will be presented at low resolution (1.0 m) together withsections of high resolution data exemplary for mid-Holocene, Preboreal and the last Glacialperiods.From the high resolution data the annual layer thickness will be derived and the possibilities ofcounting annual layers will be explored during the different periods mentioned. If possible, also theseasonal phasing and shifts thereof will be investigated for the measured species. The lowresolution data will provide an overview of the last glacial termination. The measured componentswill be discussed in terms of degree of relative change and of timing differences. Furthermore, thecontributions of the two main sources for Ca (crustal matter and sea salt aerosol) will be discussed.Presenting Author:Dr. Urs Ruth / Alfre-Wegener-Institute / 27568 Bremerhaven / Columbusstraße / Germany /+4947148311173 / uruth@awi-bremerhaven.deAbstract Reference No.: ABS-4150-0009