Fig. 1
Sampling sites along the transect from Zhongshan Station to Dome A. Thirteen snow pit samples were collected during the inland journey and the details of the geographic and sampling information can be found in Table 1. The blue circles and red points correspond to the locations where surface snow samples were collected on the return trip and were then used for mercury and major ion analysis.
Table 1. Geographic and sampling information with the mean THg concentrations for the 13 snow pits along the transect from Zhongshan Station to Dome A
76°28′43″E832400.32±0.39 [0.14 (0.09, 0.38)]200268.0816 December 201229-B70°30′11.9″S
76°49′36.5″E15971300.31±0.40 [0.23 (0.14, 0.31)]200138.52017 December 201229-C71°11′12.7″S
77°21′52.2″E20742100.14±0.11 [0.12 (0.05, 0.18)]150172.02018 December 201229-D71°58′42.8″S
77°56′45.3″E23513000.40±0.39 [0.34 (0.19, 0.43)]200121.62020 December 201229-E72°51′27.2″S
77°22′31.9″E25144000.27±0.16 [0.27 (0.15, 0.35)]20094.62021 December 201229-F73°26′7.1″S
76°59′20.7″E25514660.25±0.18 [0.21 (0.11, 0.33)]200120.62022 December 201229-G73°54′52.7″S
76°59′15.6″E26315200.13±0.17 [0.09 (0.03, 0.16)]30054.76024 December 201229-H75°27′0.7″S
76°53′42.6″E27996900.42±0.10 [0.40 (0.38, 0.43)]10029.71026 December 201229-I76°20′45.2″S
77°02′14.4″E28307920.50±0.42 [0.32 (0.23, 0.57)]20062.22028 December 201229-J77°12′2.7″S
76°58′3.7″E29678860.62±0.50 [0.51 (0.26, 0.81)]20088.08029 December 201229-K77°59′51.1″S
77°06′42.2″E31699760.69±0.73 [0.53 (0.30, 0.85)]20033.38030 December 201229-L79°05′57.1″S
76°59′42.9″E375711001.33±1.09 [1.04 (0.57, 1.65)]25025.41002 January 201329-M80°22′00″S
77°21′11″E409312480.36±0.32 [0.26 (0.19, 0.45)]30023.51005 January 2013
Fig. 2
Total mercury concentrations in the surface snow (a) and snow pit samples (b) collected along the transect from Zhongshan Station to Dome A with the altitude (a), temperature (c) (the air temperature, snow temperature and δD are included) and chemical ion contents ((d) for Na+, (e) for , (f) for Br− and (g) for ).
Fig. 3
The distribution of the sea salt enrichment factors of selected ions (Cl−, K+, Mg2 + , Br−, ) in the surface snow samples collected in different sections (coastal section between 30–600 km and inland section between 600–1248 km) of the transect from Zhongshan Station to Dome A.
Fig. 4
Distribution of the THg concentrations in snow pit 29-A with the sodium and sulphate ions and the δD values. The error bars of the total mercury concentrations represent 1σ of instrument precision.
Fig. 5
Comparison of the temporal distribution of the THg concentrations in snow pits 29-K (blue) and 29-L (red) with the sodium and sulphate ion values. The error bars of the total mercury concentrations represent 1σ of instrument precision.