A130 years deposition record of sulfate, nitrate and chloride from a high-alpine glacier

Abstract

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 tim/ice core. This corresponds to a mean time resolution of 8 (bottom) to 14 (top) data points per year. A zl~ 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 2.3 + 0.3. The mean concentrations at the beginning of the industrial time (period 1850 -1880) was 0.078 + 0.008 mg/I 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.

Anthropogenic versus natural sources of atmospheric sulphate from an Alpine ice core

“…The site has been of this site and the glaciochemical studies previglaciologically characterised and meets the ously performed there we refer to Oeschger et al requirements of an environmental and climate (1977), Haeberli et al (1983), Alean et al, (1983), archive (Oeschger et al, 1977;Alean et al, 1983;Schotterer et al, (1985), Wagenbach et al (1988), Haeberli et al, 1983;Haeberli et al, 1988;Haeberli Wagenbach (1989), Geis (1989), andFunk, 1991). Studies focusing on the period Maupetit et al (1995), Dö scher et al (1995a), of industrialisation revealed that several aerosol (1996), Wagenbach et al (1996), and Wagenbach related species show a marked concentration et al (1997). increase in the ice during this century: NH+ 4 Core sections of 0.5 m length and 7.8 cm dia- (Dö scher et al, 1996), NO− 3 and SO2− 4 meter were sealed at the drilling site in polyethyl- (Wagenbach et al, 1988;Dö scher et al, 1995a), ene bags and kept frozen at −30°C until the lead , and black carbon processing started.…”

“…Studies focusing on the period Maupetit et al (1995), Dö scher et al (1995a), of industrialisation revealed that several aerosol (1996), Wagenbach et al (1996), and Wagenbach related species show a marked concentration et al (1997). increase in the ice during this century: NH+ 4 Core sections of 0.5 m length and 7.8 cm dia- (Dö scher et al, 1996), NO− 3 and SO2− 4 meter were sealed at the drilling site in polyethyl- (Wagenbach et al, 1988;Dö scher et al, 1995a), ene bags and kept frozen at −30°C until the lead , and black carbon processing started. In a cold room, the core sec- (Lavanchy et al, 1999).…”

“…The and dating samples were melted only prior to the analysis. All vials and tools were carefully pre-cleaned In 1982 two ice cores were recovered from the Colle Gnifetti, located between the two summits with ultrapure water (18 MV cm quality) in the (Dö scher et al, 1995a;Dö scher et al, 1995b;1883-1982 the uncertainty of dating is assumed to be 2 years, and further down (period Dö scher et al, 1996). In selected samples also the total (soluble and insoluble) concentrations of 1756-1882) 5 years.…”

“…[Ca2+]>20 meq l−1 was selected in line with mean (Dö scher et al, 1995a(Dö scher et al, , 1996Nickus et al, 1997).…”

“…The industrial period as Ca-rich-industrial and Ca-rich-pre-industrial, whereas those with [Ca2+]<20 meq l−1 are represents the maximum in the SO2− 4 concentration record, whereas the definition of the pre-referred to as Ca-poor-industrial and Ca-poorpre-industrial. industrial period was based on the findings that the concentrations of SO2− 4 began to increase 25th-quantile, median, and 75th-quantile of the concentrations of chemical species are summarised significantly at about 1880 (Dö scher et al, 1995a;Dö scher et al, 1996). In addition, samples were in Table 1 for all samples of the two time periods, whereas in Tables 2 and 3, the corresponding classified into two sub-groups: (1) samples with [Ca2+]>20 meq l−1, representing samples domin-values for the Ca-rich and Ca-poor samples are given.…”