Abstract
Concentrations of trace gases trapped in ice are considered to develop uniquely from direct snow/atmosphere interactions at the time of contact. This assumption relies upon limited or no biological, chemical or physical transformations occurring during transition from snow to firn to ice; a process that can take decades to complete. Here, we present the first evidence of environmental alteration due to in situ microbial metabolism of trace gases (methyl halides and dimethyl sulfide) in polar snow. We collected evidence for ongoing microbial metabolism from an Arctic and an Antarctic location during different years. Methyl iodide production in the snowpack decreased significantly after exposure to enhanced UV radiation. Our results also show large variations in the production and consumption of other methyl halides, including methyl bromide and methyl chloride, used in climate interpretations. These results suggest that this long-neglected microbial activity could constitute a potential source of error in climate history interpretations, by introducing a so far unappreciated source of bias in the quantification of atmospheric-derived trace gases trapped within the polar ice caps.
| Original language | English |
|---|---|
| Article number | 0729 |
| Number of pages | 10 |
| Journal | Journal of the Royal Society Interface |
| Volume | 14 |
| Issue number | 137 |
| DOIs | |
| Publication status | Published - 20 Dec 2017 |
Bibliographical note
© 2017 The Royal Society. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.Keywords
- Antarctic
- Arctic
- Firn
- Methyl bromide
- Methyl iodide
- Antarctic Regions
- Atmosphere/chemistry
- Sulfides/analysis
- Hydrocarbons, Brominated/analysis
- Bacteria/isolation & purification
- Hydrocarbons, Iodinated/analysis
- Methyl Chloride/analysis
- Snow/chemistry
- Arctic Regions
- Ice Cover/chemistry
