A new continuous high-resolution detection system for sulphate in ice cores

Annals of Glaciology, Vol. 45, p. 178-182, 2007

M. Bigler, A. Svensson and J.P. Steffensen
Ice and Climate, The Niels Bohr Institute, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark
P. Kaufmann
Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland

ABSTRACT.
Sulphate (SO₄^-2 is a major ion found in polar ice cores and is related to different aerosol sources and processes. Explosive volcanic eruptions, even far away, can cause distinct sulphate peaks in ice core records. Thus, a robust sulphate detection system which is suitable for fieldwork and which enables the measurement of sulphate at high temporal resolution is of great interest. In this study, we present the adaptation of a new continuous flow analysis system for sulphate that is based on a spectrophotometric method using dimethylsulfonazo III and an inline reactor column containing barium sulphate particles. The method shows a detection limit of ~70 ng g^-1 and a linear range up to at least 3000 ng g^_-1. It is simple, robust and less prone to interferences compared to the previously used method.