In the paper “Fast depletion of gaseous mercury in the Kongsvegen Glacier snowpack in Svalbard” by Xavier Fain et al. (Geophysical Research Letters, L06826, doi:10.1029/2005GL025223, 2006), an error has been pointed out in the calculation of GEM lifetimes and derived kinetic constants. Table 1 presents the corrected data.
|Depth, cm||τ,a hours||k, b cm3.molecule−1.s−1|
|20||3.4 ± 0.2||8.2 × 10−13|
|40||3.3 ± 0.1||8.4 × 10−13|
|57||3.7 ± 0.1||7.6 × 10−13|
 The calculated lifetime of GEM in the Snowpack Interstitial Air (SIA) of Kongsvegen Glacier has been evaluated to about ∼3.5 hours, which is close to the lifetime of GEM observed during Atmospheric Mercury Depletion Events (AMDE) [see, e.g., Skov et al., 2004; Gauchard et al., 2005]. The SIA seems to be affected by GEM oxidation which can lead to GEM depletion with concentrations as low as ∼0.4 ng.m−3 close to the surface instead of ∼1.7 ng/m3 in the atmosphere above the snow. This interstitial air event is similar to AMDE and could then be so-called Interstitial Air Mercury Depletion Event (IAMDE). Finally, AMDE and IAMDE could exist independently as observed in this study, even if the chemical processes involved in both phenomenon could be the same.