Table 1. Regional data synthesis over sulfur (SSO4) concentration in atmospheric deposition (cdep), sulfur isotopic composition (δ34SSO4) in atmospheric deposition (δdep), and sulfur isotopic composition (δ34S) in bedrock (δrock) in northern Sweden and on the Kola Peninsula.
Parameter Parameter Median Mean Std Dev Min Max Data source*
cdep (mg/L) N. Sweden
0.48
0.57
0.32
0.13
1.7
Observed annual cdep between 1982 and 2017 from 11 locations in northern Sweden, also used in calculations presented in Fischer et al. (2022). cdep is composed of 9% sea spray and 91% of fossil fuel combustion.
Kola Peninsula
0.90
1.42
1.5
0.11
10.2
Observed annual cdep between 1990 and 2017 from 13 locations on or in the vicinity of the Kola Peninsula (Arctic Monitoring and Assessment Programme, 2006; Äyräs et al., 1995; EBAS, 2021; Malinovsky et al., 2002; Reimann et al., 1997). cdep is composed of 8% sea spray and 92% of fossil fuel combustion.
δdep (‰) N. Sweden
+5.4
+5.3
0.69
+3.8
+7.0
Reported values of δ34SSO4 in samples of snow and precipitation from the Kalix River Basin, which encompasses the Imetjoki stream, between 1990 and 1991 (Ingri et al., 1997), also used in Fischer et al. (2022).
Kola Peninsula
+6.6
+6.9
1.07
+4.3
+8.7
Reported values of δ34SSO4 in epiphytic moss samples (Hylocomium splendens and Pleurozium schreberi) from the Kola Peninsula during the summer 1994 (de Caritat et al., 1997). Since epiphytic mosses relies foremost on air for moisture and nutrients they provide long-term average sulfur isotopic values close to the isotopic composition of atmospheric deposition with only minor (< 1−2‰) isotopic fractionation (assimilation) during the uptake in the plant (Liu et al., 2009; Migaszewski et al., 2010; Xiao et al., 2015).
δrock (‰) N. Sweden
&
Kola Peninsula
−0.60
−0.54
1.0
−3.4
+3.3
Reported δ34S-values for sulfide minerals of magmatic origin (pyrite-chalcopyrite deposits) at the copper mine Aitik in northern Sweden (Yngström et al., 1986), as also used in Fischer et al. (2022). Due to the magmatic origin of the Khibiny massif, sulfide minerals are likely to also have isotopic values close to 0‰, which justifies using the values reported by Yngström et al. (1986) also for the Khibiny dataset.
See details in Supporting Information S2. * See details in Supporting Information S2. * See details in Supporting Information S2. * See details in Supporting Information S2. * See details in Supporting Information S2. * See details in Supporting Information S2. * See details in Supporting Information S2. * See details in Supporting Information S2.