A 130 years deposition record of sulfate, nitrate and chloride from a high-alpine glacier

An ice core from a high-alpine glacier (Grenzgletscher, Colle Gnifetti, Monte Rosa massif, 4450 m a.s.l., Switzerland) was used to reconstruct the pollution history of Central-Europe. Concentrations of the most important acidifying species sulfate and nitrate as well as of chloride were measured in 1151 samples with 5 cm resolution from the top 60 m of a 109 m long fim/ice core. This corresponds to a mean time resolution of 8 (bottom) to 14 (top) data points per year. A Pb-210 nuclear dating showed that the ice core covers a time period between 1850 - 1981 and that the mean accumulation rate was 0.33 m water equivalent per year. Between the two time periods 1850 - 1880 and 1965 - 1981 the mean sulfate concentrations increased by a factor of 5.8 +/- 0.9 and for nitrate by a factor of 23 +/- 0.3. The mean concentrations at the beginning of the industrial time (period 1850 - 1880) was 0.078 +/- 0.008 mg/l for sulfate and 0.067 +/- 0.005 mg/l for nitrate. The mean chloride concentration was 0.047 +/- 0.004 mg/l and did not show a trend in concentration over the time period investigated. A distribution analysis of the measured concentrations for the two time periods 1850 - 1865 and 1965 - 1981 was performed which showed that the data have a nearly log-normal distribution.