Comprehensive 1000-year climatic history from an intermediate ice core from the Berkner Island South Dome

Abstract

Berkner Island is a marine ice sheet grounded on bedrock within the Filchner-Ronne Ice Shelf. In 1994/95 two ice cores of intermediate depth were retrieved, one from the North dome ("R1", 151 m deep, 700 years) and one from the South dome ("B25", 181 m deep, 1200 years). For the chemical analysis of the B25 core a new methodical approach has been developed: A continuous ice core melter was used to provide decontaminated sample, which was fed both into continuous flow analysis systems for conductivity, microparticles, Ca++, and NH4+ (the latter two provided by the University of Berne) as well as into a discrete sampler for subsequent ion chromatographic anion measurement. A detailed volcanic chronology and clear seasonal variabilities allow for good dating of the cores. Here we will discuss the seasonality of selected aerosol species as well as regional and temporal variations of accumulation, stable isotopes, and concentration of biogenic sulfur species, sea salt, and microparticles. Long term records will be presented for both cores. This allows us to assess the representativity of climatic records from this site for the surrounding region